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• "Default approach" when creating a class from scratch: getters for everything, or limited access?

  - by Prog

  Until recently I always had getters (and sometimes setters but not always) for all the fields in my class. It was my 'default': very automatic and I never doubted it. However recently some discussions on this site made me realize maybe it's not the best approach. When you create a class, you often don't know exactly how it's going to be used in the future by other classes. So in that sense, it's good to have getters and setter for all of the fields in the class. So other classes could use it in the future any way they want. Allowing this flexibility doesn't require you to over engineer anything, only to provide getters. However some would say it's better to limit the access to a class, and only allow access to certain fields, while other fields stay completely private. What is your 'default' approach when building a class from scratch? Do you make getters for all the fields? Or do you always choose selectively which fields to expose through a getter and which to keep completely private?

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• C#: Struct Constructor: "fields must be fully assigned before control is returned to the caller."

  - by Rosarch

  Here is a struct I am trying to write: public struct AttackTraits { public AttackTraits(double probability, int damage, float distance) { Probability = probability; Distance = distance; Damage = damage; } private double probability; public double Probability { get { return probability; } set { if (value > 1 || value < 0) { throw new ArgumentOutOfRangeException("Probability values must be in the range [0, 1]"); } probability = value; } } public int Damage { get; set; } public float Distance { get; set; } } This results in the following compilation errors: The 'this' object cannot be used before all of its fields are assigned to Field 'AttackTraits.probability' must be fully assigned before control is returned to the caller Backing field for automatically implemented property 'AttackTraits.Damage' must be fully assigned before control is returned to the caller. Consider calling the default constructor from a constructor initializer. Backing field for automatically implemented property 'AttackTraits.Distance' must be fully assigned before control is returned to the caller. Consider calling the default constructor from a constructor initializer. What am I doing wrong?

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• Sybase: how can I remove non-printable characters from CHAR or VARCHAR fields with SQL?

  - by Kenny Drobnack

  I'm working with a Sybase database that seems to have non-printable characters in some of the string fields and this is throwing off some of our processing code. At first glance, it seemed to only be newlines and carriage returns, but we also have an ASCII code 27 in there - an ESC character, some accented characters, and some other oddities in there. I have no direct access to change the database, so changing the bad data isn't an option, yet. For now I have to make do with just filtering it out. We're trying to export the table data from one database and load it into a database used by another application in a nightly batch process. Ideally, I'd like to have a function that I can pass a list of characters and just have Sybase return the data with those characters removed. I'd like to keep it something we could do in plain SQL if possible. Something like this to remove characters that are ASCII 0 - 31. select str_replace(FIELD1, (0-31), NULL) as FIELD1, str_replace(FIELD2, (0-31), NULL) as FIELD2 from TABLE So far, str_replace is the nearest I can find, but it only allows replacing one string with another. No support for character ranges and won't let me do the above. We're running on Sybase ASE 12.5 on Unix servers.

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• How do I change the spacing between fields in a DataForm?

  - by Simon_Weaver

  How do I change the spacing between fields in a DataForm in Silverlight? I've tried editing the template but cannot find what I need. I thought all I needed to do was change the MinHeight and Margin of the DataField style, but that doesn't seem to do it. <Style TargetType="dataFormToolkit:DataField"> <Setter Property="IsTabStop" Value="False"/> <Setter Property="Margin" Value="2"/> <Setter Property="MinHeight" Value="5"/> <Setter Property="Template"> <Setter.Value> <ControlTemplate TargetType="dataFormToolkit:DataField"> <ContentControl x:Name="ContentControl" Foreground="{TemplateBinding Foreground}" HorizontalContentAlignment="Stretch" IsTabStop="False" VerticalAlignment="Center"/> </ControlTemplate> </Setter.Value> </Setter> </Style> I've found a number of articles about styling DataForm but many of them seem to be out of date. I don't see anything in the complete extracted template in Blend that corresponds to spacing.

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• How to put foreign key constraints on a computed fields in sql server?

  - by Asaf R

  Table A has a computed field called Computed1. It's persisted and not null. Also, it always computes to an expression which is char(50). It's also unique and has a unique key constraint on it. Table B has a field RefersToComputed1, which should refer to a valid Computed1 value. Trying to create a foreign key constraint on B's RefersToComputed1 that references A' Computed1 leads to the following error: Error SQL01268: .Net SqlClient Data Provider: Msg 1753, Level 16, State 0, Line 1 Column 'B.RefersToComputed1' is not the same length or scale as referencing column 'A.Computed1' in foreign key 'FK_B_A'. Columns participating in a foreign key relationship must be defined with the same length and scale. Q: Why is this error created? Are there special measures needed for foreign keys for computed columns, and if so what are they? Summary: The specific problem rises from computed, char based, fields being varchar. Hence, Computed1 is varchar(50) and not char(50). It's best to have a cast surrounding a computed field's expression to force it to a specific type. Credit goes to Cade Roux for this tip.

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• How do I populate these fields from existing data?

  - by dmanexe

  I'm not sure how to make a few parts of my form to populate from data from an array I'm passing from the database. First is this <select> object. The key estimate_lead_id in the database holds the value, and I want the dropdown to auto-select based on the value from the database. <select name="estimate_lead_id"> <? foreach($leads->result() as $lead) { ?> <option value="<?=$lead->id?>"><?=$lead->lead_name?></option> <? } ?> </select> Second (this is a little more complex), I have created a script that loops through and gets all of the items from each respective category. What I can't get it to do though is loop through these items and only display the items in the estimate, and then fill the fields with the respective values from the database. <?php foreach ($items['items_poolconcretedecking']->result() as $item) { ?> <input type="checkbox" name="measure[<?=$item->id?>][checkmark]" value="<?=$item->id?>"> <input class="item_mult" value="" type="text" name="measure[<?=$item->id?>][quantity]" /> <?php } ?>

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• Using javascript to add form fields, but what will the new name be?

  - by user1322844

  After reading this post: using javascript to add form fields.. but below, not to the side? I've made the button work! But I don't know how to receive the output. This is what I entered. var counter = 0; function addNew() { // Get the main Div in which all the other divs will be added var mainContainer = document.getElementById('mainContainer'); // Create a new div for holding text and button input elements var newDiv = document.createElement('div'); // Create a new text input var newText = document.createElement('input'); newText.type = "input"; newText.maxlength = "50"; newText.maxlimit = "50"; newText.size = "60"; newText.value = counter; // Create a new button input var newDelButton = document.createElement('input'); newDelButton.type = "button"; newDelButton.value = "Delete"; // Append new text input to the newDiv newDiv.appendChild(newText); // Append new button input to the newDiv newDiv.appendChild(newDelButton); // Append newDiv input to the mainContainer div mainContainer.appendChild(newDiv); counter++; // Add a handler to button for deleting the newDiv from the mainContainer newDelButton.onclick = function() { mainContainer.removeChild(newDiv); } } </script> With this in the form: <input type="button" size="3" cols="30" value="Add" onClick="addNew()"> So, what will the new field names be? I don't understand enough of the coding to figure out what I'm telling it to. Good thing there are other smart folks out there for me to lean on! Thanks for any answers.

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• In .NET, how do I prevent, or handle, tampering with form data of disabled fields before submission?

  - by David

  Hi, If a disabled drop-down list is dynamically rendered to the page, it is still possible to use Firebug, or another tool, to tamper with the submitted value, and to remove the "disabled" HTML attribute. This code: protected override void OnLoad(EventArgs e) { var ddlTest = new DropDownList() {ID="ddlTest", Enabled = false}; ddlTest.Items.AddRange(new [] { new ListItem("Please select", ""), new ListItem("test 1", "1"), new ListItem("test 2", "2") }); Controls.Add(ddlTest); } results in this HTML being rendered: <select disabled="disabled" id="Properties_ddlTest" name="Properties$ddlTest"> <option value="" selected="selected">Please select</option> <option value="1">test 1</option> <option value="2">test 2</option> </select> The problem occurs when I use Firebug to remove the "disabled" attribute, and to change the selected option. On submission of the form, and re-creation of the field, the newly generated control has the correct value by the end of OnLoad, but by OnPreRender, it has assumed the identity of the submitted control and has been given the submitted form value. .NET seems to have no way of detecting the fact that the field was originally created in a disabled state and that the submitted value was faked. This is understandable, as there could be legitimate, client-side functionality that would allow the disabled attribute to be removed. Is there some way, other than a brute force approach, of detecting that this field's value should not have been changed? I see the brute force approach as being something crap, like saving the correct value somewhere while still in OnLoad, and restoring the value in the OnPreRender. As some fields have dependencies on others, that would be unacceptable to me.

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• Does Microsoft Access use the PK fields for anything?

  - by chrismay

  Ok this is going to sound strange, but I have inherited an app that is an Access front end with a SQL Server backend. I am in the process of writing a new front end for it, but... we need to continue using the access front end for a while even after we deploy my new front end for reasons I won't go into. So both the existing Access app and my new app will need to be able to access and work with the data. The problem is the database design is a nightmare. For example some simple parent-child table relationships have like 4 and 5 part composite primary keys. I would REALLY like to remove these PKs and replace them with unique constraints or whatever, and add a new column to each of these tables called ID that is just an identity. If I change the PK and FKs on these tables to more managable fields, will the Access app have problems? What I mean is, does access use the meta data from the tables (PK and FK info) in such a way that it would break the app to change these?

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• How do I insert null fields with Perl's DBD::Pg?

  - by User1

  I have a Perl script inserting data into Postgres according to a pipe delimited text file. Sometimes, a field is null (as expected). However, Perl makes this field into an empty string and the Postgres insert statement fails. Here's a snippet of code: use DBI; #Connect to the database. $dbh=DBI-connect('dbi:Pg:dbname=mydb','mydb','mydb',{AutoCommit=1,RaiseError=1,PrintError=1}); #Prepare an insert. $sth=$dbh-prepare("INSERT INTO mytable (field0,field1) SELECT ?,?"); while (<){ #Remove the whitespace chomp; #Parse the fields. @field=split(/\|/,$_); print "$_\n"; #Do the insert. $sth-execute($field[0],$field[1]); } And if the input is: a|1 b| c|3 EDIT: Use this input instead. a|1|x b||x c|3|x It will fail at b|. DBD::Pg::st execute failed: ERROR: invalid input syntax for integer: "" I just want it to insert a null on field1 instead. Any ideas? EDIT: I simplified the input at the last minute. The old input actually made it work for some reason. So now I changed the input to something that will make the program fail. Also note that field1 is a nullable integer datatype.

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• Copy not null and not empty fields from one object to another object of the same type(Objects are same type) in java

  - by Chinni

  I am using hibernate, struts, extjs in my project. I have a Customer object with these fields: custId, custName, address, phone and in my project from UI side I get an object customer with custName. So I need to update the above object(custName is unique). I have only one object with the same customer name. So I will get that object using customer name (object from DB). Now I have to save the object with the updated customer name. If I save as follows I have Customer Object from UI, is cust Customer cust1 = getCustomerByName(cust.getCustName()); cust.setCustId(cust1.getCustId()); save(cust); If I do this I lose the customer address and phone number. So, how can I copy one object not null or not empty field values to another object of same type. Can any one please help. I just stuck here. It's stopping me to save. Thanks in advance!

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• 1and1: Unable to host an external domain

  - by Django Reinhardt

  I'm sorry if this isn't the right place for this question, but I'm presently having difficulties with my hosting provider (1and1). Two weeks ago, two of my clients bought hosting from them on my recommendation, but as it turned out, 1and1 are having severe technical difficulties. Right now non of their hosting packages are able to accept ANY external domains. So either you pay the costs of transferring the registrar of your domain, or you use the ugly 1and1 domain name. Not any good for a hosting company of 1and1's reputation! They have been promising me for two weeks that they're going to fix the problem, but as you have probably guessed by now, that hasn't been the case. I would like to know if a) Anyone else is in the same boat as me, and b) If there are other comparably reputable hosting providers that I should consider moving to instead? Very disappointing! :( Note: This is for 1and1 in the UK. I imagine it isn't affecting users in other countries(?) Clarification: 1and1 are unable to accept ANY external domains. That means that even if you update your DNS details on your domain, their system cannot be updated to add your external domain to your account.

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• Need to validate a scientific spreadsheet written in Java

  - by geejay

  I need a validation framework, for an app written in Java, Eclipse RCP. The UI is a simple spreadsheet with many input fields and many output fields. The user input needs to be validated, for example: Thresholds for numerical fields Required fields for certain operations Context-sensitive help based on the validation results Multi-field validation, e.g a field is valid depending upon the values in other fields Wondering if there is anything out there?

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• Recommend good shared hosting [closed]

  - by Django Reinhardt

  It seems that everyone has something bad to say about the "big" shared hosting sites like 1and1, HostGator, GoDaddy, etc. but what are the ones you've had GOOD experiences with? I'm going to focus this question on LAMP stacks, given that they're the most popular option for shared hosting, but if you have an especially good experience with a different stack. Good shared hosting should be: Competitively priced - But not at the expense of... Fully featured - Email, PHP, MySQL, but what else? Highly customizable - Do you have access to advanced features like being able to deliver static content? Up to date - Do they run PHP4 as standard, or do they run the latest version? Customer service - When you have a problem are they rude and unhelpful? Do they take ages to reply? So how about it? Who have YOU have a good experience with?

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• ASP.NET MVC & EF4 Entity Framework - Are there any performance concerns in using the entities vs retrieving only the fields i need?

  - by Ant

  Lets say we have 3 tables, Users, Products, Purchases. There is a view that needs to display the purchases made by a user. I could lookup the data required by doing: from p in DBSet<Purchases>.Include("User").Include("Product") select p; However, I am concern that this may have a performance impact because it will retrieve the full objects. Alternatively, I could select only the fields i need: from p in DBSet<Purchases>.Include("User").Include("Product") select new SimplePurchaseInfo() { UserName = p.User.name, Userid = p.User.Id, ProductName = p.Product.Name ... etc }; So my question is: Whats the best practice in doing this? == EDIT Thanks for all the replies. [QUESTION 1]: I want to know whether all views should work with flat ViewModels with very specific data for that view, or should the ViewModels contain the entity objects. Real example: User reviews Products var query = from dr in productRepository.FindAllReviews() where dr.User.UserId = 'userid' select dr; string sql = ((ObjectQuery)query).ToTraceString(); SELECT [Extent1].[ProductId] AS [ProductId], [Extent1].[Comment] AS [Comment], [Extent1].[CreatedTime] AS [CreatedTime], [Extent1].[Id] AS [Id], [Extent1].[Rating] AS [Rating], [Extent1].[UserId] AS [UserId], [Extent3].[CreatedTime] AS [CreatedTime1], [Extent3].[CreatorId] AS [CreatorId], [Extent3].[Description] AS [Description], [Extent3].[Id] AS [Id1], [Extent3].[Name] AS [Name], [Extent3].[Price] AS [Price], [Extent3].[Rating] AS [Rating1], [Extent3].[ShopId] AS [ShopId], [Extent3].[Thumbnail] AS [Thumbnail], [Extent3].[Creator_UserId] AS [Creator_UserId], [Extent4].[Comment] AS [Comment1], [Extent4].[DateCreated] AS [DateCreated], [Extent4].[DateLastActivity] AS [DateLastActivity], [Extent4].[DateLastLogin] AS [DateLastLogin], [Extent4].[DateLastPasswordChange] AS [DateLastPasswordChange], [Extent4].[Email] AS [Email], [Extent4].[Enabled] AS [Enabled], [Extent4].[PasswordHash] AS [PasswordHash], [Extent4].[PasswordSalt] AS [PasswordSalt], [Extent4].[ScreenName] AS [ScreenName], [Extent4].[Thumbnail] AS [Thumbnail1], [Extent4].[UserId] AS [UserId1], [Extent4].[UserName] AS [UserName] FROM [ProductReviews] AS [Extent1] INNER JOIN [Users] AS [Extent2] ON [Extent1].[UserId] = [Extent2].[UserId] LEFT OUTER JOIN [Products] AS [Extent3] ON [Extent1].[ProductId] = [Extent3].[Id] LEFT OUTER JOIN [Users] AS [Extent4] ON [Extent1].[UserId] = [Extent4].[UserId] WHERE N'615005822' = [Extent2].[UserId] or from d in productRepository.FindAllProducts() from dr in d.ProductReviews where dr.User.UserId == 'userid' orderby dr.CreatedTime select new ProductReviewInfo() { product = new SimpleProductInfo() { Id = d.Id, Name = d.Name, Thumbnail = d.Thumbnail, Rating = d.Rating }, Rating = dr.Rating, Comment = dr.Comment, UserId = dr.UserId, UserScreenName = dr.User.ScreenName, UserThumbnail = dr.User.Thumbnail, CreateTime = dr.CreatedTime }; SELECT [Extent1].[Id] AS [Id], [Extent1].[Name] AS [Name], [Extent1].[Thumbnail] AS [Thumbnail], [Extent1].[Rating] AS [Rating], [Extent2].[Rating] AS [Rating1], [Extent2].[Comment] AS [Comment], [Extent2].[UserId] AS [UserId], [Extent4].[ScreenName] AS [ScreenName], [Extent4].[Thumbnail] AS [Thumbnail1], [Extent2].[CreatedTime] AS [CreatedTime] FROM [Products] AS [Extent1] INNER JOIN [ProductReviews] AS [Extent2] ON [Extent1].[Id] = [Extent2].[ProductId] INNER JOIN [Users] AS [Extent3] ON [Extent2].[UserId] = [Extent3].[UserId] LEFT OUTER JOIN [Users] AS [Extent4] ON [Extent2].[UserId] = [Extent4].[UserId] WHERE N'userid' = [Extent3].[UserId] ORDER BY [Extent2].[CreatedTime] ASC [QUESTION 2]: Whats with the ugly outer joins?

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• Photo gallery for Blogspot blog

  - by Django Reinhardt

  I don't think this is entirely possible, but here we go: I have a friend who has a Blogspot blog. He has posts with text, posts with videos and posts with photos... and he was wondering if there's any way to turn the posts which are just photos into a thumbnail gallery screen on his blog. So for example, let's say he has 20 photo posts on his blog with the label Skiing Holiday 2009 (horrible example, I know). Is there a way of having a post created for his blog that displays those photos as thumbnails, linking through to their full size versions? I just don't think it's possible, but I'm really hoping someone will be able to offer a solution (or even a place where I could find a solution). Thanks a lot.

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• What are good Python and/or Django deployment solutions?

  - by e-satis

  For now I use some mix between virtual_env, pip and Fabric. This allows to: install required libs; generate dynamic content; isolate installation; push everything through ssh. It works well, I just want to know if there are other tools around. The only problem I could think of is that it's a lot of to set up every time. It doesn't solve database / media files migration issues either, but maybe I should just open another question for this specific subject. Eventually, I don't know how to automatize the server setup. I'd love to have a tool to let me configure Apache/Lighttp/Cherokee and MySQL automatically. Related : How django projects can be deployed with minimal installation works?

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• Casting objects in C# (ASP.Net MVC)

  - by Mortanis

  I'm coming from a background in ColdFusion, and finally moving onto something modern, so please bear with me. I'm running into a problem casting objects. I have two database tables that I'm using as Models - Residential and Commercial. Both of them share the majority of their fields, though each has a few unique fields. I've created another class as a container that contains the sum of all property fields. Query the Residential and Commercial, stuff it into my container, cunningly called Property. This works fine. However, I'm having problems aliasing the fields from Residential/Commercial onto Property. It's quite easy to create a method for each property: fillPropertyByResidential(Residential source) and fillPropertyByCommercial(Commercial source), and alias the variables. That also works fine, but quite obviously will copy a bunch of code - all those fields that are shared between the two main Models. So, I'd like a generic fillPropertyBySource() that takes the object, and detects if it's Residential or Commercial, fills the particular fields of each respective type, then do all the fields in common. Except, I gather in C# that variables created inside an If are only in the scope of the if, so I'm not sure how to do this. public property fillPropertyBySource(object source) { property prop = new property(); if (source is Residential) { Residential o = (Residential)source; //Fill Residential only fields } else if (source is Commercial) { Commercial o = (Commercial)source; //Fill Commercial only fields } //Fill fields shared by both prop.price = (int)o.price; prop.bathrooms = (float)o.bathrooms; return prop; } "o" being a Commercial or Residential only exists within the scope of the if. How do I detect the original type of the source object and take action? Bear with me - the shift from ColdFusion into a modern language is pretty..... difficult. More so since I'm used to procedural code and MVC is a massive paradigm shift. Edit: I should include the error: The name 'o' does not exist in the current context For the aliases of price and bathrooms in the shared area.

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• Issues running python scripts in Command Prompt (Specifically with command line arguments)?

  - by dmanatunga

  I am trying to run my python scripts in DOS without calling python.exe first. I am specifically doing this in relation to running django-admin.py. I have C:\Python26 and C:\Python26\Scripts in my PATH. However, if I try running django-admin.py by doing: django-admin.py startproject helloworld I get the message: Type 'django-admin.py help' for usage. Now, after some experimentation, I realized the problem is that the secondary arguments to these scripts are not being passed for some reason, since I tried it with a some other python scripts I have. I know I could avoid this problem by simply doing: python C:\Python26\Scripts\django-admin.py startproject helloworld But I know it should be possible to run the first command only and get it to work, because I had it working before. I've looked everywhere, and not many places have been helpful so any idea would be useful for me at this point.

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• Need help with tweaking a Dropdown with three options, user selects one - a hidden div appears with correct fields

  - by Jack

  Hello Again, I posted a question on here and got an answer within minutes I'm hoping the wizards on here can help me again. Okay so I'm using a script I found online to try and add this function to a shopping cart form. Here's the setup. I have a payment method dropdown with Visa, Mastercard and Bank Withdrawal as the options. For the credit cards I have one hidden div with a certain set of fields, and for the bank I have another hidden div. Each of the divs have named ID's - #payCredit and #payBank The css for both have margin: 0px and display: none; Here's a peice of javascript I used successfuly on a shipping address checkbox `function toggleLayer( whichLayer ) { var elem, vis; if( document.getElementById ) // this is the way the standards work elem = document.getElementById( whichLayer ); else if( document.all ) // this is the way old msie versions work elem = document.all[whichLayer]; else if( document.layers ) // this is the way nn4 works elem = document.layers[whichLayer]; vis = elem.style; // if the style.display value is blank we try to figure it out here if(vis.display==''&&elem.offsetWidth!=undefined&&elem.offsetHeight!=undefined) vis.display = (elem.offsetWidth!=0&&elem.offsetHeight!=0)?'block':'none'; vis.display = (vis.display==''||vis.display=='block')?'none':'block'; }` I was hoping I could change it slightly to meet my needs. Here's the dropdown <label>Payment Method:</label> <select name="payment" id="payment" class="dropdown3" style="width:8em"> <option selected="selected">Select</option> <option value="Visa" onclick="javascript:toggleLayer('payCredit');">Visa</option> <option value="MasterCard" onclick="javascript:toggleLayer('payCredit');">Mastercard</option> <option value="Direct" onclick="javascript:toggleLayer('payBank');">Direct Withdraw</option> </select></li> The current result is that it kinda works. I can open the dropdown and select Visa and it appears, if I select Visa again it disappears, if I select Visa and then select bank, both appear. You can see what i'm working on here - http://test.sharevetcare.com/bestfriends/cart3.html

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• Solution for this SQL query?

  - by homeWorkBoy

  Suppose you have these tables: Table Name: Salesman Fields: S_ID(Primary Key), Name Table Name: Region_1 Fields: Reg_ID(Primary Key), S_ID(Foreign Key), sales Table Name: Region_2 Fields: Reg_ID(Primary Key), S_ID(Foreign Key), sales Table Name: Region_3 Fields: Reg_ID(Primary Key), S_ID(Foreign Key), sales Table Name: Region_4 Fields: Reg_ID(Primary Key), S_ID(Foreign Key), sales Query 1: Find out total of sales of each salesman in all the regions. Query 2: Find out total of sales of a particual salesman in all the regions. (if the first one is solved I think this will be easy. :-) )

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• Does anyone get zero-height select fields in Firefox 3.6.3?

  - by user350635

  If you open this HTML in Firefox 3.6.3 (confirmed in some earlier versions too), and click the drawStuff() link repeatedly, it doesn't render the contents of the last div consistently. Looking more closely it seems like it's rendering select fields with height=0. Any idea why this would happen? <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <title> A Page </title> <script type="text/javascript"> function drawStuff() { for (var i = 1; i <= 5; i++) { var curHtmlArr = []; for (var j = 0; j < 5; j++){ curHtmlArr.push("<select>"); curHtmlArr.push(getOptgroup()); curHtmlArr.push(getOptgroup()); curHtmlArr.push(getOptgroup()); curHtmlArr.push("<\/select>"); } var foobar = document.getElementById('elem_' + i); foobar.innerHTML = curHtmlArr.join(''); } } function getOptgroup(){ var htmlArr = []; htmlArr.push('<optgroup label="Whatever">'); for (var ii = 0; ii < 32; ii++){ htmlArr.push(' <option value="' + ii + '"> Blah ' + "<\/option>"); } htmlArr.push("<\/optgroup>"); return htmlArr.join(''); } </script> </head> <body> <table border=1 style="width:900px;" summary="A Table"> <tr> <td> <div id="elem_1"></div> </td> <td> <div id="elem_2"></div> </td> <td> <div id="elem_3"></div> </td> <td> <div id="elem_4"></div> </td> <td> <div>abc</div> <div id="elem_5"></div> </td> </tr> </table> <a href="javascript:drawStuff()"> drawStuff() </a> <script type="text/javascript"> drawStuff(); </script> </body> </html>

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• What's New in ASP.NET 4

  - by Navaneeth

  The .NET Framework version 4 includes enhancements for ASP.NET 4 in targeted areas. Visual Studio 2010 and Microsoft Visual Web Developer Express also include enhancements and new features for improved Web development. This document provides an overview of many of the new features that are included in the upcoming release. This topic contains the following sections: ASP.NET Core Services ASP.NET Web Forms ASP.NET MVC Dynamic Data ASP.NET Chart Control Visual Web Developer Enhancements Web Application Deployment with Visual Studio 2010 Enhancements to ASP.NET Multi-Targeting ASP.NET Core Services ASP.NET 4 introduces many features that improve core ASP.NET services such as output caching and session state storage. Extensible Output Caching Since the time that ASP.NET 1.0 was released, output caching has enabled developers to store the generated output of pages, controls, and HTTP responses in memory. On subsequent Web requests, ASP.NET can serve content more quickly by retrieving the generated output from memory instead of regenerating the output from scratch. However, this approach has a limitation — generated content always has to be stored in memory. On servers that experience heavy traffic, the memory requirements for output caching can compete with memory requirements for other parts of a Web application. ASP.NET 4 adds extensibility to output caching that enables you to configure one or more custom output-cache providers. Output-cache providers can use any storage mechanism to persist HTML content. These storage options can include local or remote disks, cloud storage, and distributed cache engines. Output-cache provider extensibility in ASP.NET 4 lets you design more aggressive and more intelligent output-caching strategies for Web sites. For example, you can create an output-cache provider that caches the "Top 10" pages of a site in memory, while caching pages that get lower traffic on disk. Alternatively, you can cache every vary-by combination for a rendered page, but use a distributed cache so that the memory consumption is offloaded from front-end Web servers. You create a custom output-cache provider as a class that derives from the OutputCacheProvider type. You can then configure the provider in the Web.config file by using the new providers subsection of the outputCache element For more information and for examples that show how to configure the output cache, see outputCache Element for caching (ASP.NET Settings Schema). For more information about the classes that support caching, see the documentation for the OutputCache and OutputCacheProvider classes. By default, in ASP.NET 4, all HTTP responses, rendered pages, and controls use the in-memory output cache. The defaultProvider attribute for ASP.NET is AspNetInternalProvider. You can change the default output-cache provider used for a Web application by specifying a different provider name for defaultProvider attribute. In addition, you can select different output-cache providers for individual control and for individual requests and programmatically specify which provider to use. For more information, see the HttpApplication.GetOutputCacheProviderName(HttpContext) method. The easiest way to choose a different output-cache provider for different Web user controls is to do so declaratively by using the new providerName attribute in a page or control directive, as shown in the following example: <%@ OutputCache Duration="60" VaryByParam="None" providerName="DiskCache" %> Preloading Web Applications Some Web applications must load large amounts of data or must perform expensive initialization processing before serving the first request. In earlier versions of ASP.NET, for these situations you had to devise custom approaches to "wake up" an ASP.NET application and then run initialization code during the Application_Load method in the Global.asax file. To address this scenario, a new application preload manager (autostart feature) is available when ASP.NET 4 runs on IIS 7.5 on Windows Server 2008 R2. The preload feature provides a controlled approach for starting up an application pool, initializing an ASP.NET application, and then accepting HTTP requests. It lets you perform expensive application initialization prior to processing the first HTTP request. For example, you can use the application preload manager to initialize an application and then signal a load-balancer that the application was initialized and ready to accept HTTP traffic. To use the application preload manager, an IIS administrator sets an application pool in IIS 7.5 to be automatically started by using the following configuration in the applicationHost.config file: <applicationPools> <add name="MyApplicationPool" startMode="AlwaysRunning" /> </applicationPools> Because a single application pool can contain multiple applications, you specify individual applications to be automatically started by using the following configuration in the applicationHost.config file: <sites> <site name="MySite" id="1"> <application path="/" serviceAutoStartEnabled="true" serviceAutoStartProvider="PrewarmMyCache" > <!-- Additional content --> </application> </site> </sites> <!-- Additional content --> <serviceAutoStartProviders> <add name="PrewarmMyCache" type="MyNamespace.CustomInitialization, MyLibrary" /> </serviceAutoStartProviders> When an IIS 7.5 server is cold-started or when an individual application pool is recycled, IIS 7.5 uses the information in the applicationHost.config file to determine which Web applications have to be automatically started. For each application that is marked for preload, IIS7.5 sends a request to ASP.NET 4 to start the application in a state during which the application temporarily does not accept HTTP requests. When it is in this state, ASP.NET instantiates the type defined by the serviceAutoStartProvider attribute (as shown in the previous example) and calls into its public entry point. You create a managed preload type that has the required entry point by implementing the IProcessHostPreloadClient interface, as shown in the following example: public class CustomInitialization : System.Web.Hosting.IProcessHostPreloadClient { public void Preload(string[] parameters) { // Perform initialization. } } After your initialization code runs in the Preload method and after the method returns, the ASP.NET application is ready to process requests. Permanently Redirecting a Page Content in Web applications is often moved over the lifetime of the application. This can lead to links to be out of date, such as the links that are returned by search engines. In ASP.NET, developers have traditionally handled requests to old URLs by using the Redirect method to forward a request to the new URL. However, the Redirect method issues an HTTP 302 (Found) response (which is used for a temporary redirect). This results in an extra HTTP round trip. ASP.NET 4 adds a RedirectPermanent helper method that makes it easy to issue HTTP 301 (Moved Permanently) responses, as in the following example: RedirectPermanent("/newpath/foroldcontent.aspx"); Search engines and other user agents that recognize permanent redirects will store the new URL that is associated with the content, which eliminates the unnecessary round trip made by the browser for temporary redirects. Session State Compression By default, ASP.NET provides two options for storing session state across a Web farm. The first option is a session state provider that invokes an out-of-process session state server. The second option is a session state provider that stores data in a Microsoft SQL Server database. Because both options store state information outside a Web application's worker process, session state has to be serialized before it is sent to remote storage. If a large amount of data is saved in session state, the size of the serialized data can become very large. ASP.NET 4 introduces a new compression option for both kinds of out-of-process session state providers. By using this option, applications that have spare CPU cycles on Web servers can achieve substantial reductions in the size of serialized session state data. You can set this option using the new compressionEnabled attribute of the sessionState element in the configuration file. When the compressionEnabled configuration option is set to true, ASP.NET compresses (and decompresses) serialized session state by using the .NET Framework GZipStreamclass. The following example shows how to set this attribute. <sessionState mode="SqlServer" sqlConnectionString="data source=dbserver;Initial Catalog=aspnetstate" allowCustomSqlDatabase="true" compressionEnabled="true" /> ASP.NET Web Forms Web Forms has been a core feature in ASP.NET since the release of ASP.NET 1.0. Many enhancements have been in this area for ASP.NET 4, such as the following: The ability to set meta tags. More control over view state. Support for recently introduced browsers and devices. Easier ways to work with browser capabilities. Support for using ASP.NET routing with Web Forms. More control over generated IDs. The ability to persist selected rows in data controls. More control over rendered HTML in the FormView and ListView controls. Filtering support for data source controls. Enhanced support for Web standards and accessibility Setting Meta Tags with the Page.MetaKeywords and Page.MetaDescription Properties Two properties have been added to the Page class: MetaKeywords and MetaDescription. These two properties represent corresponding meta tags in the HTML rendered for a page, as shown in the following example: <head id="Head1" runat="server"> <title>Untitled Page</title> <meta name="keywords" content="keyword1, keyword2' /> <meta name="description" content="Description of my page" /> </head> These two properties work like the Title property does, and they can be set in the @ Page directive. For more information, see Page.MetaKeywords and Page.MetaDescription. Enabling View State for Individual Controls A new property has been added to the Control class: ViewStateMode. You can use this property to disable view state for all controls on a page except those for which you explicitly enable view state. View state data is included in a page's HTML and increases the amount of time it takes to send a page to the client and post it back. Storing more view state than is necessary can cause significant decrease in performance. In earlier versions of ASP.NET, you could reduce the impact of view state on a page's performance by disabling view state for specific controls. But sometimes it is easier to enable view state for a few controls that need it instead of disabling it for many that do not need it. For more information, see Control.ViewStateMode. Support for Recently Introduced Browsers and Devices ASP.NET includes a feature that is named browser capabilities that lets you determine the capabilities of the browser that a user is using. Browser capabilities are represented by the HttpBrowserCapabilities object which is stored in the HttpRequest.Browser property. Information about a particular browser's capabilities is defined by a browser definition file. In ASP.NET 4, these browser definition files have been updated to contain information about recently introduced browsers and devices such as Google Chrome, Research in Motion BlackBerry smart phones, and Apple iPhone. Existing browser definition files have also been updated. For more information, see How to: Upgrade an ASP.NET Web Application to ASP.NET 4 and ASP.NET Web Server Controls and Browser Capabilities. The browser definition files that are included with ASP.NET 4 are shown in the following list: •blackberry.browser •chrome.browser •Default.browser •firefox.browser •gateway.browser •generic.browser •ie.browser •iemobile.browser •iphone.browser •opera.browser •safari.browser A New Way to Define Browser Capabilities ASP.NET 4 includes a new feature referred to as browser capabilities providers. As the name suggests, this lets you build a provider that in turn lets you write custom code to determine browser capabilities. In ASP.NET version 3.5 Service Pack 1, you define browser capabilities in an XML file. This file resides in a machine-level folder or an application-level folder. Most developers do not need to customize these files, but for those who do, the provider approach can be easier than dealing with complex XML syntax. The provider approach makes it possible to simplify the process by implementing a common browser definition syntax, or a database that contains up-to-date browser definitions, or even a Web service for such a database. For more information about the new browser capabilities provider, see the What's New for ASP.NET 4 White Paper. Routing in ASP.NET 4 ASP.NET 4 adds built-in support for routing with Web Forms. Routing is a feature that was introduced with ASP.NET 3.5 SP1 and lets you configure an application to use URLs that are meaningful to users and to search engines because they do not have to specify physical file names. This can make your site more user-friendly and your site content more discoverable by search engines. For example, the URL for a page that displays product categories in your application might look like the following example: http://website/products.aspx?categoryid=12 By using routing, you can use the following URL to render the same information: http://website/products/software The second URL lets the user know what to expect and can result in significantly improved rankings in search engine results. the new features include the following: The PageRouteHandler class is a simple HTTP handler that you use when you define routes. You no longer have to write a custom route handler. The HttpRequest.RequestContext and Page.RouteData properties make it easier to access information that is passed in URL parameters. The RouteUrl expression provides a simple way to create a routed URL in markup. The RouteValue expression provides a simple way to extract URL parameter values in markup. The RouteParameter class makes it easier to pass URL parameter values to a query for a data source control (similar to FormParameter). You no longer have to change the Web.config file to enable routing. For more information about routing, see the following topics: ASP.NET Routing Walkthrough: Using ASP.NET Routing in a Web Forms Application How to: Define Routes for Web Forms Applications How to: Construct URLs from Routes How to: Access URL Parameters in a Routed Page Setting Client IDs The new ClientIDMode property makes it easier to write client script that references HTML elements rendered for server controls. Increasing use of Microsoft Ajax makes the need to do this more common. For example, you may have a data control that renders a long list of products with prices and you want to use client script to make a Web service call and update individual prices in the list as they change without refreshing the entire page. Typically you get a reference to an HTML element in client script by using the document.GetElementById method. You pass to this method the value of the id attribute of the HTML element you want to reference. In the case of elements that are rendered for ASP.NET server controls earlier versions of ASP.NET could make this difficult or impossible. You were not always able to predict what id values ASP.NET would generate, or ASP.NET could generate very long id values. The problem was especially difficult for data controls that would generate multiple rows for a single instance of the control in your markup. ASP.NET 4 adds two new algorithms for generating id attributes. These algorithms can generate id attributes that are easier to work with in client script because they are more predictable and that are easier to work with because they are simpler. For more information about how to use the new algorithms, see the following topics: ASP.NET Web Server Control Identification Walkthrough: Making Data-Bound Controls Easier to Access from JavaScript Walkthrough: Making Controls Located in Web User Controls Easier to Access from JavaScript How to: Access Controls from JavaScript by ID Persisting Row Selection in Data Controls The GridView and ListView controls enable users to select a row. In previous versions of ASP.NET, row selection was based on the row index on the page. For example, if you select the third item on page 1 and then move to page 2, the third item on page 2 is selected. In most cases, is more desirable not to select any rows on page 2. ASP.NET 4 supports Persisted Selection, a new feature that was initially supported only in Dynamic Data projects in the .NET Framework 3.5 SP1. When this feature is enabled, the selected item is based on the row data key. This means that if you select the third row on page 1 and move to page 2, nothing is selected on page 2. When you move back to page 1, the third row is still selected. This is a much more natural behavior than the behavior in earlier versions of ASP.NET. Persisted selection is now supported for the GridView and ListView controls in all projects. You can enable this feature in the GridView control, for example, by setting the EnablePersistedSelection property, as shown in the following example: <asp:GridView id="GridView2" runat="server" PersistedSelection="true"> </asp:GridView> FormView Control Enhancements The FormView control is enhanced to make it easier to style the content of the control with CSS. In previous versions of ASP.NET, the FormView control rendered it contents using an item template. This made styling more difficult in the markup because unexpected table row and table cell tags were rendered by the control. The FormView control supports RenderOuterTable, a property in ASP.NET 4. When this property is set to false, as show in the following example, the table tags are not rendered. This makes it easier to apply CSS style to the contents of the control. <asp:FormView ID="FormView1" runat="server" RenderTable="false"> For more information, see FormView Web Server Control Overview. ListView Control Enhancements The ListView control, which was introduced in ASP.NET 3.5, has all the functionality of the GridView control while giving you complete control over the output. This control has been made easier to use in ASP.NET 4. The earlier version of the control required that you specify a layout template that contained a server control with a known ID. The following markup shows a typical example of how to use the ListView control in ASP.NET 3.5. <asp:ListView ID="ListView1" runat="server"> <LayoutTemplate> <asp:PlaceHolder ID="ItemPlaceHolder" runat="server"></asp:PlaceHolder> </LayoutTemplate> <ItemTemplate> <% Eval("LastName")%> </ItemTemplate> </asp:ListView> In ASP.NET 4, the ListView control does not require a layout template. The markup shown in the previous example can be replaced with the following markup: <asp:ListView ID="ListView1" runat="server"> <ItemTemplate> <% Eval("LastName")%> </ItemTemplate> </asp:ListView> For more information, see ListView Web Server Control Overview. Filtering Data with the QueryExtender Control A very common task for developers who create data-driven Web pages is to filter data. This traditionally has been performed by building Where clauses in data source controls. This approach can be complicated, and in some cases the Where syntax does not let you take advantage of the full functionality of the underlying database. To make filtering easier, a new QueryExtender control has been added in ASP.NET 4. This control can be added to EntityDataSource or LinqDataSource controls in order to filter the data returned by these controls. Because the QueryExtender control relies on LINQ, but you do not to need to know how to write LINQ queries to use the query extender. The QueryExtender control supports a variety of filter options. The following lists QueryExtender filter options. Term Definition SearchExpression Searches a field or fields for string values and compares them to a specified string value. RangeExpression Searches a field or fields for values in a range specified by a pair of values. PropertyExpression Compares a specified value to a property value in a field. If the expression evaluates to true, the data that is being examined is returned. OrderByExpression Sorts data by a specified column and sort direction. CustomExpression Calls a function that defines custom filter in the page. For more information, see QueryExtenderQueryExtender Web Server Control Overview. Enhanced Support for Web Standards and Accessibility Earlier versions of ASP.NET controls sometimes render markup that does not conform to HTML, XHTML, or accessibility standards. ASP.NET 4 eliminates most of these exceptions. For details about how the HTML that is rendered by each control meets accessibility standards, see ASP.NET Controls and Accessibility. CSS for Controls that Can be Disabled In ASP.NET 3.5, when a control is disabled (see WebControl.Enabled), a disabled attribute is added to the rendered HTML element. For example, the following markup creates a Label control that is disabled: <asp:Label id="Label1" runat="server"   Text="Test" Enabled="false" /> In ASP.NET 3.5, the previous control settings generate the following HTML: <span id="Label1" disabled="disabled">Test</span> In HTML 4.01, the disabled attribute is not considered valid on span elements. It is valid only on input elements because it specifies that they cannot be accessed. On display-only elements such as span elements, browsers typically support rendering for a disabled appearance, but a Web page that relies on this non-standard behavior is not robust according to accessibility standards. For display-only elements, you should use CSS to indicate a disabled visual appearance. Therefore, by default ASP.NET 4 generates the following HTML for the control settings shown previously: <span id="Label1" class="aspNetDisabled">Test</span> You can change the value of the class attribute that is rendered by default when a control is disabled by setting the DisabledCssClass property. CSS for Validation Controls In ASP.NET 3.5, validation controls render a default color of red as an inline style. For example, the following markup creates a RequiredFieldValidator control: <asp:RequiredFieldValidator ID="RequiredFieldValidator1" runat="server"   ErrorMessage="Required Field" ControlToValidate="RadioButtonList1" /> ASP.NET 3.5 renders the following HTML for the validator control: <span id="RequiredFieldValidator1"   style="color:Red;visibility:hidden;">RequiredFieldValidator</span> By default, ASP.NET 4 does not render an inline style to set the color to red. An inline style is used only to hide or show the validator, as shown in the following example: <span id="RequiredFieldValidator1"   style"visibility:hidden;">RequiredFieldValidator</span> Therefore, ASP.NET 4 does not automatically show error messages in red. For information about how to use CSS to specify a visual style for a validation control, see Validating User Input in ASP.NET Web Pages. CSS for the Hidden Fields Div Element ASP.NET uses hidden fields to store state information such as view state and control state. These hidden fields are contained by a div element. In ASP.NET 3.5, this div element does not have a class attribute or an id attribute. Therefore, CSS rules that affect all div elements could unintentionally cause this div to be visible. To avoid this problem, ASP.NET 4 renders the div element for hidden fields with a CSS class that you can use to differentiate the hidden fields div from others. The new classvalue is shown in the following example: <div class="aspNetHidden"> CSS for the Table, Image, and ImageButton Controls By default, in ASP.NET 3.5, some controls set the border attribute of rendered HTML to zero (0). The following example shows HTML that is generated by the Table control in ASP.NET 3.5: <table id="Table2" border="0"> The Image control and the ImageButton control also do this. Because this is not necessary and provides visual formatting information that should be provided by using CSS, the attribute is not generated in ASP.NET 4. CSS for the UpdatePanel and UpdateProgress Controls In ASP.NET 3.5, the UpdatePanel and UpdateProgress controls do not support expando attributes. This makes it impossible to set a CSS class on the HTMLelements that they render. In ASP.NET 4 these controls have been changed to accept expando attributes, as shown in the following example: <asp:UpdatePanel runat="server" class="myStyle"> </asp:UpdatePanel> The following HTML is rendered for this markup: <div id="ctl00_MainContent_UpdatePanel1" class="expandoclass"> </div> Eliminating Unnecessary Outer Tables In ASP.NET 3.5, the HTML that is rendered for the following controls is wrapped in a table element whose purpose is to apply inline styles to the entire control: FormView Login PasswordRecovery ChangePassword If you use templates to customize the appearance of these controls, you can specify CSS styles in the markup that you provide in the templates. In that case, no extra outer table is required. In ASP.NET 4, you can prevent the table from being rendered by setting the new RenderOuterTable property to false. Layout Templates for Wizard Controls In ASP.NET 3.5, the Wizard and CreateUserWizard controls generate an HTML table element that is used for visual formatting. In ASP.NET 4 you can use a LayoutTemplate element to specify the layout. If you do this, the HTML table element is not generated. In the template, you create placeholder controls to indicate where items should be dynamically inserted into the control. (This is similar to how the template model for the ListView control works.) For more information, see the Wizard.LayoutTemplate property. New HTML Formatting Options for the CheckBoxList and RadioButtonList Controls ASP.NET 3.5 uses HTML table elements to format the output for the CheckBoxList and RadioButtonList controls. To provide an alternative that does not use tables for visual formatting, ASP.NET 4 adds two new options to the RepeatLayout enumeration: UnorderedList. This option causes the HTML output to be formatted by using ul and li elements instead of a table. OrderedList. This option causes the HTML output to be formatted by using ol and li elements instead of a table. For examples of HTML that is rendered for the new options, see the RepeatLayout enumeration. Header and Footer Elements for the Table Control In ASP.NET 3.5, the Table control can be configured to render thead and tfoot elements by setting the TableSection property of the TableHeaderRow class and the TableFooterRow class. In ASP.NET 4 these properties are set to the appropriate values by default. CSS and ARIA Support for the Menu Control In ASP.NET 3.5, the Menu control uses HTML table elements for visual formatting, and in some configurations it is not keyboard-accessible. ASP.NET 4 addresses these problems and improves accessibility in the following ways: The generated HTML is structured as an unordered list (ul and li elements). CSS is used for visual formatting. The menu behaves in accordance with ARIA standards for keyboard access. You can use arrow keys to navigate menu items. (For information about ARIA, see Accessibility in Visual Studio and ASP.NET.) ARIA role and property attributes are added to the generated HTML. (Attributes are added by using JavaScript instead of included in the HTML, to avoid generating HTML that would cause markup validation errors.) Styles for the Menu control are rendered in a style block at the top of the page, instead of inline with the rendered HTML elements. If you want to use a separate CSS file so that you can modify the menu styles, you can set the Menu control's new IncludeStyleBlock property to false, in which case the style block is not generated. Valid XHTML for the HtmlForm Control In ASP.NET 3.5, the HtmlForm control (which is created implicitly by the <form runat="server"> tag) renders an HTML form element that has both name and id attributes. The name attribute is deprecated in XHTML 1.1. Therefore, this control does not render the name attribute in ASP.NET 4. Maintaining Backward Compatibility in Control Rendering An existing ASP.NET Web site might have code in it that assumes that controls are rendering HTML the way they do in ASP.NET 3.5. To avoid causing backward compatibility problems when you upgrade the site to ASP.NET 4, you can have ASP.NET continue to generate HTML the way it does in ASP.NET 3.5 after you upgrade the site. To do so, you can set the controlRenderingCompatibilityVersion attribute of the pages element to "3.5" in the Web.config file of an ASP.NET 4 Web site, as shown in the following example: <system.web>   <pages controlRenderingCompatibilityVersion="3.5"/> </system.web> If this setting is omitted, the default value is the same as the version of ASP.NET that the Web site targets. (For information about multi-targeting in ASP.NET, see .NET Framework Multi-Targeting for ASP.NET Web Projects.) ASP.NET MVC ASP.NET MVC helps Web developers build compelling standards-based Web sites that are easy to maintain because it decreases the dependency among application layers by using the Model-View-Controller (MVC) pattern. MVC provides complete control over the page markup. It also improves testability by inherently supporting Test Driven Development (TDD). Web sites created using ASP.NET MVC have a modular architecture. This allows members of a team to work independently on the various modules and can be used to improve collaboration. For example, developers can work on the model and controller layers (data and logic), while the designer work on the view (presentation). For tutorials, walkthroughs, conceptual content, code samples, and a complete API reference, see ASP.NET MVC 2. Dynamic Data Dynamic Data was introduced in the .NET Framework 3.5 SP1 release in mid-2008. This feature provides many enhancements for creating data-driven applications, such as the following: A RAD experience for quickly building a data-driven Web site. Automatic validation that is based on constraints defined in the data model. The ability to easily change the markup that is generated for fields in the GridView and DetailsView controls by using field templates that are part of your Dynamic Data project. For ASP.NET 4, Dynamic Data has been enhanced to give developers even more power for quickly building data-driven Web sites. For more information, see ASP.NET Dynamic Data Content Map. Enabling Dynamic Data for Individual Data-Bound Controls in Existing Web Applications You can use Dynamic Data features in existing ASP.NET Web applications that do not use scaffolding by enabling Dynamic Data for individual data-bound controls. Dynamic Data provides the presentation and data layer support for rendering these controls. When you enable Dynamic Data for data-bound controls, you get the following benefits: Setting default values for data fields. Dynamic Data enables you to provide default values at run time for fields in a data control. Interacting with the database without creating and registering a data model. Automatically validating the data that is entered by the user without writing any code. For more information, see Walkthrough: Enabling Dynamic Data in ASP.NET Data-Bound Controls. New Field Templates for URLs and E-mail Addresses ASP.NET 4 introduces two new built-in field templates, EmailAddress.ascx and Url.ascx. These templates are used for fields that are marked as EmailAddress or Url using the DataTypeAttribute attribute. For EmailAddress objects, the field is displayed as a hyperlink that is created by using the mailto: protocol. When users click the link, it opens the user's e-mail client and creates a skeleton message. Objects typed as Url are displayed as ordinary hyperlinks. The following example shows how to mark fields. [DataType(DataType.EmailAddress)] public object HomeEmail { get; set; } [DataType(DataType.Url)] public object Website { get; set; } Creating Links with the DynamicHyperLink Control Dynamic Data uses the new routing feature that was added in the .NET Framework 3.5 SP1 to control the URLs that users see when they access the Web site. The new DynamicHyperLink control makes it easy to build links to pages in a Dynamic Data site. For information, see How to: Create Table Action Links in Dynamic Data Support for Inheritance in the Data Model Both the ADO.NET Entity Framework and LINQ to SQL support inheritance in their data models. An example of this might be a database that has an InsurancePolicy table. It might also contain CarPolicy and HousePolicy tables that have the same fields as InsurancePolicy and then add more fields. Dynamic Data has been modified to understand inherited objects in the data model and to support scaffolding for the inherited tables. For more information, see Walkthrough: Mapping Table-per-Hierarchy Inheritance in Dynamic Data. Support for Many-to-Many Relationships (Entity Framework Only) The Entity Framework has rich support for many-to-many relationships between tables, which is implemented by exposing the relationship as a collection on an Entity object. New field templates (ManyToMany.ascx and ManyToMany_Edit.ascx) have been added to provide support for displaying and editing data that is involved in many-to-many relationships. For more information, see Working with Many-to-Many Data Relationships in Dynamic Data. New Attributes to Control Display and Support Enumerations The DisplayAttribute has been added to give you additional control over how fields are displayed. The DisplayNameAttribute attribute in earlier versions of Dynamic Data enabled you to change the name that is used as a caption for a field. The new DisplayAttribute class lets you specify more options for displaying a field, such as the order in which a field is displayed and whether a field will be used as a filter. The attribute also provides independent control of the name that is used for the labels in a GridView control, the name that is used in a DetailsView control, the help text for the field, and the watermark used for the field (if the field accepts text input). The EnumDataTypeAttribute class has been added to let you map fields to enumerations. When you apply this attribute to a field, you specify an enumeration type. Dynamic Data uses the new Enumeration.ascx field template to create UI for displaying and editing enumeration values. The template maps the values from the database to the names in the enumeration. Enhanced Support for Filters Dynamic Data 1.0 had built-in filters for Boolean columns and foreign-key columns. The filters did not let you specify the order in which they were displayed. The new DisplayAttribute attribute addresses this by giving you control over whether a column appears as a filter and in what order it will be displayed. An additional enhancement is that filtering support has been rewritten to use the new QueryExtender feature of Web Forms. This lets you create filters without requiring knowledge of the data source control that the filters will be used with. Along with these extensions, filters have also been turned into template controls, which lets you add new ones. Finally, the DisplayAttribute class mentioned earlier allows the default filter to be overridden, in the same way that UIHint allows the default field template for a column to be overridden. For more information, see Walkthrough: Filtering Rows in Tables That Have a Parent-Child Relationship and QueryableFilterRepeater. ASP.NET Chart Control The ASP.NET chart server control enables you to create ASP.NET pages applications that have simple, intuitive charts for complex statistical or financial analysis. The chart control supports the following features: Data series, chart areas, axes, legends, labels, titles, and more. Data binding. Data manipulation, such as copying, splitting, merging, alignment, grouping, sorting, searching, and filtering. Statistical formulas and financial formulas. Advanced chart appearance, such as 3-D, anti-aliasing, lighting, and perspective. Events and customizations. Interactivity and Microsoft Ajax. Support for the Ajax Content Delivery Network (CDN), which provides an optimized way for you to add Microsoft Ajax Library and jQuery scripts to your Web applications. For more information, see Chart Web Server Control Overview. Visual Web Developer Enhancements The following sections provide information about enhancements and new features in Visual Studio 2010 and Visual Web Developer Express. The Web page designer in Visual Studio 2010 has been enhanced for better CSS compatibility, includes additional support for HTML and ASP.NET markup snippets, and features a redesigned version of IntelliSense for JScript. Improved CSS Compatibility The Visual Web Developer designer in Visual Studio 2010 has been updated to improve CSS 2.1 standards compliance. The designer better preserves HTML source code and is more robust than in previous versions of Visual Studio. HTML and JScript Snippets In the HTML editor, IntelliSense auto-completes tag names. The IntelliSense Snippets feature auto-completes whole tags and more. In Visual Studio 2010, IntelliSense snippets are supported for JScript, alongside C# and Visual Basic, which were supported in earlier versions of Visual Studio. Visual Studio 2010 includes over 200 snippets that help you auto-complete common ASP.NET and HTML tags, including required attributes (such as runat="server") and common attributes specific to a tag (such as ID, DataSourceID, ControlToValidate, and Text). You can download additional snippets, or you can write your own snippets that encapsulate the blocks of markup that you or your team use for common tasks. For more information on HTML snippets, see Walkthrough: Using HTML Snippets. JScript IntelliSense Enhancements In Visual 2010, JScript IntelliSense has been redesigned to provide an even richer editing experience. IntelliSense now recognizes objects that have been dynamically generated by methods such as registerNamespace and by similar techniques used by other JavaScript frameworks. Performance has been improved to analyze large libraries of script and to display IntelliSense with little or no processing delay. Compatibility has been significantly increased to support almost all third-party libraries and to support diverse coding styles. Documentation comments are now parsed as you type and are immediately leveraged by IntelliSense. Web Application Deployment with Visual Studio 2010 For Web application projects, Visual Studio now provides tools that work with the IIS Web Deployment Tool (Web Deploy) to automate many processes that had to be done manually in earlier versions of ASP.NET. For example, the following tasks can now be automated: Creating an IIS application on the destination computer and configuring IIS settings. Copying files to the destination computer. Changing Web.config settings that must be different in the destination environment. Propagating changes to data or data structures in SQL Server databases that are used by the Web application. For more information about Web application deployment, see ASP.NET Deployment Content Map. Enhancements to ASP.NET Multi-Targeting ASP.NET 4 adds new features to the multi-targeting feature to make it easier to work with projects that target earlier versions of the .NET Framework. Multi-targeting was introduced in ASP.NET 3.5 to enable you to use the latest version of Visual Studio without having to upgrade existing Web sites or Web services to the latest version of the .NET Framework. In Visual Studio 2008, when you work with a project targeted for an earlier version of the .NET Framework, most features of the development environment adapt to the targeted version. However, IntelliSense displays language features that are available in the current version, and property windows display properties available in the current version. In Visual Studio 2010, only language features and properties available in the targeted version of the .NET Framework are shown. For more information about multi-targeting, see the following topics: .NET Framework Multi-Targeting for ASP.NET Web Projects ASP.NET Side-by-Side Execution Overview How to: Host Web Applications That Use Different Versions of the .NET Framework on the Same Server How to: Deploy Web Site Projects Targeted for Earlier Versions of the .NET Framework

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• Where Have All the Ugly Forms Gone? Users and ADF Took Care Of It

  - by ultan o'broin

  Sometimes I hear that our application demos are a bit too "cutsey" and that we never talk about with any user roles that have lots of data entry as a requirement. Some (no names) consider those old clunker forms, with the myriad rows of fields, to be super-productive for data clerks. We do have such roles covered in Oracle Fusion Applications for sure. But consider what is really the issue here: productivity. Check out how the Oracle Fusion Financials Applications User Experience team went about designing for productivity when receiving and entering invoice data, for example. See how Fusion Financials caters so well for input and control of data? Central to all this is knowing the users and how they work: what tasks do they need to perform, and when. Read more about Fusion Financials productivity in the white paper, Get It Done Fast, Get It Done Right: The Oracle Fusion Financials User Experience. Now and then, I see forms that weren't designed for end user activity at all. Instead, they were designed by developers or by the IT department around the database schema. Forms with literally dozens of fields on the same page, sometimes. Forms that give the impression there was only task involved, when there may have been several. At times, completing one of these huge forms accurately became so tedious that, under pressure, it made more sense for the user to complete it quickly as possible and then let somebody else check it for accuracy and fill in the gaps from data emailed along in spreadsheet form. Data accuracy is critical in our business. Not good. Not efficient. Not productive. So here are a few basics on forms design for data entry-type user roles. A great place for developers to start exploring what is possible with forms layout is the Rich Client User Experience (RCUX) guidance on Form Layout, using ADF components. User-Centered Forms Design Considerations The starting point--something you must always keep in mind with your own design--is design for the end user. Find a representative end user, and keep that user engaged throughout the design, deployment, and test process. Consider these points in user testing those forms: Are there automated or technical solutions to entering the data that avoid manual input in the first place? For example, imports, uploads, OCR, whatever. Some day we will be able to tell Siri to do it, but leave that for now. Design your form to reflect the task involved (i.e., the business process) and not the database schema. On the form, group like fields together, logically. Eliminate duplicate data entry or prepopulate from previous data entry. Allow users to complete fields in the order they wish (i.e., no interdependency). Allow for tabbing between fields (keyboard is faster than mouse), so know how the browser supports this (see that RCUX guideline). Allow for final validation at the page level not at field-level entry. Way better for heads-down users. For example, ADF messages allow you to see a list of all validation errors on a page on a final submit or navigation action and to easily navigate to the point of error. Better still, be error tolerant. Allow users to enter data in formats they comfortable with. Bind any relevant user preference setting to the input format allowed (for example, the locale date format). Explore what data entry conversion can do for you automatically too (see the ADF converter demos, convenience patterns can also be written). Only ask for data input when it's needed. Get rid of, or hide optional fields. Cut down on the number of mandatory fields, and mark them clearly (use a *). Clearly label the fields in plain language. I am sure you may have a few more tips on forms design for data entry users. Remember the user before finding the comments.

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• How do I send automated e-mails from Drupal using Messaging and Notifications?

  - by Adrian

  I am working on a Notifications plugin, and after starting to write my notes down about how to do this, decided to just post them here. Please feel free to come make modifications and changes. Eventually I hope to post this on the Drupal handbook as well. Thanks. --Adrian Sending automated e-mails from Drupal using Messaging and Notifications To implement a notifications plugin, you must implement the following functions: Use hook_messaging, hook_token_list and hook_token_values to create the messages that will be sent. Use hook_notifications to create the subscription types Add code to fire events (eg in hook_nodeapi) Add all UI elements to allow users to subscribe/unsubscribe Understanding Messaging The Messaging module is used to compose messages that can be delivered using various formats, such as simple mail, HTML mail, Twitter updates, etc. These formats are called "send methods." The backend details do not concern us here; what is important are the following concepts: TOKENS: tokens are provided by the "tokens" module. They allow you to write keywords in square brackets, [like-this], that can be replaced by any arbitrary value. Note: the token groups you create must match the keys you add to the $events-objects[$key] array. MESSAGE KEYS: A key is a part of a message, such as the greetings line. Keys can be different for each send method. For example, a plaintext mail's greeting might be "Hi, [user]," while an HTML greeing might be "Hi, [user]," and Twitter's might just be "[user-firstname]: ". Keys can have any arbitrary name. Keys are very simple and only have a machine-readable name and a user-readable description, the latter of which is only seen by admins. MESSAGE GROUPS: A group is a bunch of keys that often, but not always, might be used together to make up a complete message. For example, a generic group might include keys for a greeting, body, closing and footer. Groups can also be "subclassed" by selecting a "fallback" group that will supply any keys that are missing. Groups are also associated with modules; I'm not sure what these are used for. Understanding Notifications The Notifications module revolves around the following concepts: SUBSCRIPTIONS: Notifications plugins may define one or more types of subscriptions. For example, notifications_content defines subscriptions for: Threads (users are notified whenever a node or its comments change) Content types (users are notified whenever a node of a certain type is created or is changed) Users (users are notified whenever another user is changed) Subscriptions refer to both the user who's subscribed, how often they wish to be notified, the send method (for Messaging) and what's being subscribed to. This last part is defined in two steps. Firstly, a plugin defines several "subscription fields" (through a hook_notifications op of the same name), and secondly, "subscription types" (also an op) defines which fields apply to each type of subscription. For example, notifications_content defines the fields "nid," "author" and "type," and the subscriptions "thread" (nid), "nodetype" (type), "author" (author) and "typeauthor" (type and author), the latter referring to something like "any STORY by JOE." Fields are used to link events to subscriptions; an event must match all fields of a subscription (for all normal subscriptions) to be delivered to the recipient. The $subscriptions object is defined in subsequent sections. Notifications prefers that you don't create these objects yourself, preferring you to call the notifications_get_link() function to create a link that users may click on, but you can also use notifications_save_subscription and notifications_delete_subscription to do it yourself. EVENTS: An event is something that users may be notified about. Plugins create the $event object then call notifications_event($event). This either sends out notifications immediately, queues them to send out later, or both. Events include the type of thing that's changed (eg 'node', 'user'), the ID of the thing that's changed (eg $node-nid, $user-uid) and what's happened to it (eg 'create'). These are, respectively, $event-type, $event-oid (object ID) and $event-action. Warning: notifications_content_nodeapi also adds a $event-node field, referring to the node itself and not just $event-oid = $node-nid. This is not used anywhere in the core notifications module; however, when the $event is passed back to the 'query' op (see below), we assume the node is still present. Events do not refer to the user they will be referred to; instead, Notifications makes the connection between subscriptions and events, using the subscriptions' fields. MATCHING EVENTS TO SUBSCRIPTIONS: An event matches a subscription if it has the same type as the event (eg "node") and if the event matches all the correct fields. This second step is determined by the "query" hook op, which is called with the $event object as a parameter. The query op is responsible for giving Notifications a value for all the fields defined by the plugin. For example, notifications_content defines the 'nid', 'type' and 'author' fields, so its query op looks like this (ignore the case where $event_or_user = 'user' for now): $event_or_user = $arg0; $event_type = $arg1; $event_or_object = $arg2; if ($event_or_user == 'event' && $event_type == 'node' && ($node = $event_or_object->node) || $event_or_user == 'user' && $event_type == 'node' && ($node = $event_or_object)) { $query[]['fields'] = array( 'nid' => $node->nid, 'type' => $node->type, 'author' => $node->uid, ); return $query; After extracting the $node from the $event, we set $query[]['fields'] to a dictionary defining, for this event, all the fields defined by the module. As you can tell from the presence of the $query object, there's way more you can do with this op, but they are not covered here. DIGESTING AND DEDUPING: Understanding the relationship between Messaging and Notifications Usually, the name of a message group doesn't matter, but when being used with Notifications, the names must follow very strict patterns. Firstly, they must start with the name "notifications," and then are followed by either "event" or "digest," depending on whether the message group is being used to represent either a single event or a group of events. For 'events,' the third part of the name is the "type," which we get from Notification's $event-type (eg: notifications_content uses 'node'). The last part of the name is the operation being performed, which comes from Notification's $event-action. For example: notifications-event-node-comment might refer to the message group used when someone comments on a node notifications-event-user-update to a user who's updated their profile Hyphens cannot appear anywhere other than to separate the parts of these words. For 'digest' messages, the third and fourth part of the name come from hook_notification's "event types" callback, specifically this line: $types[] = array( 'type' => 'node', 'action' => 'insert', ... 'digest' => array('node', 'type'), ); $types[] = array( 'type' => 'node', 'action' => 'update', ... 'digest' => array('node', 'nid'), ); In this case, the first event type (node insertion) will be digested with the notifications-digest-node-type message template providing the header and footer, likely saying something like "the following [type] was created." The second event type (node update) will be digested with the notifications-digest-node-nid message template. Data Structure and Callback Reference $event The $event object has the following members: $event-type: The type of event. Must match the type in hook_notification::"event types". {notifications_event} $event-action: The action the event describes. Most events are sorted by [$event-type][$event-action]. {notifications_event}. $event-object[$object_type]: All objects relevant to the event. For example, $event-object['node'] might be the node that the event describes. $object_type can come from the 'event types' hook (see below). The main purpose appears to be to be passed to token_replace_multiple as the second parameter. $event-object[$event-type] is assumed to exist in the short digest processing functions, but this doesn't appear to be used anywhere. Not saved in the database; loaded by hook_notifications::"event load" $event-oid: apparently unused. The id of the primary object relevant to this event (eg the node's nid). $event-module: apparently unused $event-params[$key]: Mainly a place for plugins to save random data. The main module will serialize the contents of this array but does not use it in any way. However, notifications_ui appears to do something weird with it, possibly by using subscriptions' fields as keys into this array. I'm not sure why though. hook_notifications op 'subscription types': returns an array of subscription types provided by the plugin, in the form $key = array(...) with the following members: event_type: this subscription can only match events whose $event-type has this value. Stored in the database as notifications.event_type for every individual subscription. Apparently, this can be overiden in code but I wouldn't try it (see notifications_save_subscription). fields: an unkeyed array of fields that must be matched by an event (in addition to the event_type) for it to match this subscription. Each element of this array must be a key of the array returned by op 'subscription fields' which in turn must be used by op 'query' to actually perform the matching. title: user-readable title for their subscriptions page (eg the 'type' column in user/%uid/notifications/subscriptions) description: a user-readable description. page callback: used to add a supplementary page at user/%uid/notifications/blah. This and the following are used by notifications_ui as a part of hook_menu_alter. Appears to be partially deprecated. user page: user/%uid/notifications/blah. op 'event types': returns an array of event types, with each event type being an array with the following members: type: this will match $event-type action: this will match $event-action digest: an array with two ordered (non-keyed) elements, "type" and "field." 'type' is used as an index into $event-objects. 'field' is also used to group events like so: $event-objects[$type]-$field. For example, 'field' might be 'nid' - if the object is a node, the digest lines will be grouped by node ID. Finally, both are used to find the correct Messaging template; see discussion above. description: used on the admin "Notifications-Events" page name: unused, use Messaging instead line: deprecated, use Messaging instead Other Stuff This is an example of the main query that inserts an event into the queue: INSERT INTO {notifications_queue} (uid, destination, sid, module, eid, send_interval, send_method, cron, created, conditions) SELECT DISTINCT s.uid, s.destination, s.sid, s.module, %d, // event ID s.send_interval, s.send_method, s.cron, %d, // time of the event s.conditions FROM {notifications} s INNER JOIN {notifications_fields} f ON s.sid = f.sid WHERE (s.status = 1) AND (s.event_type = '%s') // subscription type AND (s.send_interval >= 0) AND (s.uid <> %d) AND ( (f.field = '%s' AND f.intval IN (%d)) // everything from 'query' op OR (f.field = '%s' AND f.intval = %d) OR (f.field = '%s' AND f.value = '%s') OR (f.field = '%s' AND f.intval = %d)) GROUP BY s.uid, s.destination, s.sid, s.module, s.send_interval, s.send_method, s.cron, s.conditions HAVING s.conditions = count(f.sid)

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