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  • Is it getting to be time for C# to support compile-time macros?

    - by Robert Rossney
    Thus far, Microsoft's C# team has resisted adding formal compile-time macro capabilities to the language. There are aspects of programming with WPF that seem (to me, at least) to be creating some compelling use cases for macros. Dependency properties, for instance. It would be so nice to just be able to do something like this: [DependencyProperty] public string Foo { get; set; } and have the body of the Foo property and the static FooProperty property be generated automatically at compile time. Or, for another example an attribute like this: [NotifyPropertyChanged] public string Foo { get; set; } that would make the currently-nonexistent preprocessor produce this: private string _Foo; public string Foo { get { return _Foo; } set { _Foo = value; OnPropertyChanged("Foo"); } } You can implement change notification with PostSharp, and really, maybe PostSharp is a better answer to the question. I really don't know. Assuming that you've thought about this more than I have, which if you've thought about it at all you probably have, what do you think? (This is clearly a community wiki question and I've marked it accordingly.)

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  • casting vs using the 'as' keyword in the CLR

    - by Frank V
    I'm learning about design patterns and because of that I've ended using a lot of interfaces. One of my "goals" is to program to an interface, not an implementation. What I've found is that I'm doing a lot of casting or object type conversion. What I'd like to know is if there is a difference between these two methods of conversion: public interface IMyInterface { void AMethod(); } public class MyClass : IMyInterface { public void AMethod() { //Do work } // other helper methods.... } public class Implementation { IMyInterface _MyObj; MyClass _myCls1; MyClass _myCls2; public Implementation() { _MyObj = new MyClass(); // What is the difference here: _myCls1 = (MyClass)_MyObj; _myCls2 = (_MyObj as MyClass); } } If there is a difference, is there a cost difference or how does this affect my program? Hopefully this makes sense. Sorry for the bad example; it is all I could think of... Update: What is "in general" the preferred method? (I had a question similar to this posted in the 'answers'. I moved it up here at the suggestion of Michael Haren. Also, I want to thank everyone who's provided insight and perspective on my question.

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  • Bind an Incode DataTemplate in WPF

    - by Mike Bynum
    I have a WPF Application which is using MVVM. I know that there ways of doing this in XAML but I am working on a plugin architecture and came up with a solution where a plugin exposes it's viewmodel to my plugin host's viewmodel and it's datatemplate. I want to leave the lifetime management of the plugin view up to WPF. I have tried having the plugins expose a UserControl but ran into issues when WPF decided to dispose of my UserControl so I would not reattach it without weird hacky work arounds. I am having issues getting some sort of binding working to where i can bind a control to the data and it's template to my data template. I have a ViewModel which looks something like: public class MyViewModel { public DataTemplate SelectedTemplate{ get; set;} public object SelectedViewModel {get; set;} } The selected template and viewmodel are determined somewhere else in the code but are irrelevant to my question. My question is how i can bind to a DataTemplate so that I know how to display the data shown in the SelectedViewModel. The DataTemplate is a DataTemplate created incode which respresents: <DataTemplate DataType="{x:Type vm:MyViewModel}"> <v:MyUserControl /> </DataTemplate> I have tried: <UserControl Template="{Binding Path=SelectedTemplate}" Content="{Binding Path=SelectedViewModel"} /> But UserControl expects a control template and not a data template.

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  • Attempt to use a while loop for the 'next' arg of a for loop generates #arg error

    - by JerryK
    Am attempting to teach myself to program using Tcl. The task i've set myself to motivate my learning of Tcl is to solve the 8 queens problem. My approach to creating a program is to successively 'prototype' a solution. I have asked an earlier question related to the correctly laying out the nested for loops and received a helpful answer. To my dismay I find that the next development of my code creates the same interpreter error : "wrong # args" I have been careful to have an open brace at the end of the line preceding the while loop command. I've also tried to put the arguments of the whileloop in braces. This generates a different error. I have sincerely tried to understand the Tcl syntax man page - not too successfully - suggested by the answerer of my earlier question. Here is the code set allowd 1 set notallowd 0 for {set r1p 1} {$r1p <= 8} {incr r1p } { puts "1st row q placed at $r1p" ;# re-initialize r2 'free for q placemnt' array after every change of r1 q pos: for {set i 1 } {$i <= 8} {incr i} { set r2($i) $allowd } for { set r2($r1p) $notallowd ; set r2([expr $r1p-1]) $notallowd ; set r2([expr $r1p+1]) $notallowd ; set r2p 1} {$r2p <= 8} { ;# 'next' arg of r2 forloop will be a whileloop : while r2($r2p)== $notallowd incr r2p } { puts "2nd row q placed at $r2p" ;# end of 'commnd' arg of r2 forloop } } Where am I going wrong? EDIT : to provide clear reply @slebetman As stated in my text, I did brace the arguments of the whileloop (indeed that was how i first wrote the code) below is exactly the layout of the r2 forloop tried: for { set r2($r1p) $notallowd ; set r2([expr $r1p-1]) $notallowd ; set r2([expr $r1p+1]) $notallowd ; set r2p 1} {$r2p <= 8} { ;# 'next' arg of r2 forloop will be a whileloop : while { r2($r2p)== $notallowd } { incr r2p } } { puts "2nd row q placed at $r2p" ;# end of 'commnd' arg of r2 forloop } but this generates the fatal interpreter error : "unknown math function 'r2' while compiling while { r2($r2p .... "

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  • C++ -- Why should we use operator -> to access member functions of a SmartPtr?

    - by q0987
    Hello all, The question is given in the last two lines of code. template<class T> // template class for smart class SmartPtr { // pointers-to-T objects public: SmartPtr(T* realPtr = 0); T* operator->() const; T& operator*() const; T* Detach( void ) { T* pData = pointee; pointee = NULL; return pData; } private: T *pointee; ... }; class TestClass {} SmartPtr<TestClass> sPtr(new TestClass); TestClass* ptrA = sPtr->Detach(); // why I always see people use this method to access member functions of a Smart pointer. We can use sPtr-> b/c we have defined operator->() in SmartPtr. TestClass* ptrB = sPtr.Detach(); // Question: Is this a valid C++ way? If not, why? Thank you

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  • JQuery: Current, Well-Formatted, Printable Documentation?

    - by Eli
    Hi All, I'm looking for a current (1.2), well-formatted, printable version of the jQuery documentation. I've checked the alternative resources page and see the PDF versions from CF and Java, but both are out of date. The jQuery site has the API browser with "Printable Version" in the toolbox, but it prints terribly, and I don't really want to print one page or tab at a time. I have a hard time believing that there is no print doc for a tool this popular - all I want is a simple listing with descriptions and examples ON PAPER. Am I missing something? I can buy one of the books if I need to, but not sure which is for the current version. Thanks! Update: I can see that somebody voted this down. I know it's a pretty basic question, but it is not asked lightly or frivolously. I have made a pretty solid effort to find this on my own, and am pretty good at finding information when I need it. Perhaps the person who thought the question not worth asking knows where to find the print doc?

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  • passing reference of class to another class android error

    - by prolink007
    I recently asked the precursor to this question and had a great reply. However, when i was working this into my android application i am getting an unexpected error and was wondering if everyone could take a look at my code and help me see what i am doing wrong. Link to the initial question: passing reference of class to another class My ERROR: "The constructor ConnectDevice(new View.OnClickListener(){}) is undefined" The above is an error detected by eclipse. Thanks in advance! Below are My code snippets: public class SmartApp extends Activity { /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.intro); final Button connectDeviceButton = (Button) findViewById(R.id.connectDeviceButton); connectDeviceButton.setOnClickListener( new View.OnClickListener() { @Override public void onClick(View v) { Thread cThread = new Thread(new ConnectDevice(this)); cThread.start(); } }); } } public class ConnectDevice implements Runnable { private boolean connected; private SmartApp smartAppRef; private ObjectInputStream ois; public ConnectDevice(SmartApp smartAppRef) { this.smartAppRef = smartAppRef; } }

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  • Tell bots apart from human visitors for stats?

    - by Pekka
    I am looking to roll my own simple web stats script. The only major obstacle on the road, as far as I can see, is telling human visitors apart from bots. I would like to have a solution for that which I don't need to maintain on a regular basis (i.e. I don't want to update text files with bot-related User-agents). Is there any open service that does that, like Akismet does for spam? Or is there a PHP project that is dedicated to recognizing spiders and bots and provides frequent updates? To clarify: I'm not looking to block bots. I do not need 100% watertight results. I just want to exclude as many as I can from my stats. In know that parsing the user-Agent is an option but maintaining the patterns to parse for is a lot of work. My question is whether there is any project or service that does that already. Bounty: I thought I'd push this as a reference question on the topic. The best / most original / most technically viable contribution will receive the bounty amount.

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  • Extended slice that goes to beginning of sequence with negative stride

    - by recursive
    Bear with me while I explain my question. Skip down to the bold heading if you already understand extended slice list indexing. In python, you can index lists using slice notation. Here's an example: >>> A = list(range(10)) >>> A[0:5] [0, 1, 2, 3, 4] You can also include a stride, which acts like a "step": >>> A[0:5:2] [0, 2, 4] The stride is also allowed to be negative, meaning the elements are retrieved in reverse order: >>> A[5:0:-1] [5, 4, 3, 2, 1] But wait! I wanted to see [4, 3, 2, 1, 0]. Oh, I see, I need to decrement the start and end indices: >>> A[4:-1:-1] [] What happened? It's interpreting -1 as being at the end of the array, not the beginning. I know you can achieve this as follows: >>> A[4::-1] [4, 3, 2, 1, 0] But you can't use this in all cases. For example, in a method that's been passed indices. My question is: Is there any good pythonic way of using extended slices with negative strides and explicit start and end indices that include the first element of a sequence? This is what I've come up with so far, but it seems unsatisfying. >>> A[0:5][::-1] [4, 3, 2, 1, 0]

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  • Website. VoteUp or VoteDown Videos. How to restrict users voting multiple times?

    - by DJDonaL3000
    Im working on a website (html,css,javascript, ajax, php,mysql), and I want to restrict the number of times a particular user votes for a particular video. Its similar to the YouTube system where you can voteUp or voteDown a particular video. Each vote involves adding a row to the video.votes table, which logs the time, vote direction(up or down), the client IPaddress( using PHP: $ip = $_SERVER['REMOTE_ADDR']; ), and of course the ID of the video in question. Adding votes is as simple as; (pseudocode): Javascript:onClick( vote( a,b,c,d ) ), which passes variables to PHP insertion script via ajax, and finally we replace the voteing buttons with a "Thank You For Voting" message. THE PROBLEM: If you reload/refresh the page after voting, you can vote again, and again, and again, you get the point. MY QUESTION: How do you limit the amount of times a particular user votes for a particular video?? MY THOUGHTS: Do you use cookies, and add a new cookie with the id of the video. And check for a cookie before you insert a new vote.? OR Before you insert the vote, do you use the IPaddress and the videoID to see if this same user(IP) has voted for this same video(vidID) in the past 24hrs(mktime), and either allow or dissallow the voteInsertion based on this query? OR Do you just not care? Take the assumption that most users are sane, and have better things to do than refresh pages and vote repeatedly.?? Any suggestions or ideas welcome.

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  • How to run <script src= > tag from javascript

    - by Gleeb
    I am having some difficulties implementing Paypal buttons with backbone.js The problem is that the button is implemented in a script tag: <script src="paypal-button.min.js?merchant=YOUR_MERCHANT_ID" data-button="buynow" data-name="My product" data-amount="1.00"></script> which i cant run from Handlebars.js because the </script> tag is closing the handlebars <script> I cant use eval(), or i don't understand how i am supposed to do that with the . So there you have it. i am kind of stuck. I am out of ideas on how to implement this button with backbone.js the last resort is to ask the server to produce html pages with the script in them and then load them to the page. i am just refusing to believe that JavaScript has no way to take care of this. Please help. This question relates to another question i asked in this subject. Is it possible to use JavaScript inside handlebars.js template Thank you.

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  • Proper Memory Management for Objective-C Method

    - by Justin
    Hi, I'm programming an iPhone app and I had a question about memory management in one of my methods. I'm still a little new to managing memory manually, so I'm sorry if this question seems elementary. Below is a method designed to allow a number pad to place buttons in a label based on their tag, this way I don't need to make a method for each button. The method works fine, I'm just wondering if I'm responsible for releasing any of the variables I make in the function. The application crashes if I try to release any of the variables, so I'm a little confused about my responsibility regarding memory. Here's the method: FYI the variable firstValue is my label, it's the only variable not declared in the method. -(IBAction)inputNumbersFromButtons:(id)sender { UIButton *placeHolderButton = [[UIButton alloc] init]; placeHolderButton = sender; NSString *placeHolderString = [[NSString alloc] init]; placeHolderString = [placeHolderString stringByAppendingString:firstValue.text]; NSString *addThisNumber = [[NSString alloc] init]; int i = placeHolderButton.tag; addThisNumber = [NSString stringWithFormat:@"%i", i]; NSString *newLabelText = [[NSString alloc] init]; newLabelText = [placeHolderString stringByAppendingString:addThisNumber]; [firstValue setText:newLabelText]; //[placeHolderButton release]; //[placeHolderString release]; //[addThisNumber release]; //[newLabelText release]; } The application works fine with those last four lines commented out, but it seems to me like I should be releasing these variables here. If I'm wrong about that I'd welcome a quick explanation about when it's necessary to release variables declared in functions and when it's not. Thanks.

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  • What is a modern C++ approach to structures containing symbolic constants?

    - by Ken
    enum bool { FALSE = 0, TRUE = 1 }; I'm wondering how to translate this in a modern C++ approach and if there is a well suited container for that; i know that the enum are not really that appreciated, but i can't think about a real alternative in the C++ world. What if would like to associate the execution of a particular method with a state? Ok, this is the part where i will be more verbose. I would like to stress the fact that i'm asking about structures symbolic constants and not about TRUE and FALSE, i'm not that "needy". Suppose that i have a structure that can represent several states with their own constants enum semaphore { GREEN = 0, ORANGE = 1, RED = 2 }; this is C code, now my question is about how to do the same in C++ if there is a better way. My question continue when i ask about the possibility to do something like an automatic triggering when a change of state will occur, for example: int main{ ... semaphore = 1; ... } and without any extra statements this has to trigger a method() just because the semaphore is now orange. I hope that is more clear now.

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  • Using the AutoComplete feature of ComboBox, while limiting values to those in the list?

    - by Schmuli
    In WinForms 2.0, a ComboBox has an Auto-Complete feature, that displays a custom Drop-Down list with only the values that start with the entered text. However, if I want to limit valid values to only those that appear in the ComboBox's list of items, I can do that by setting the DropDownStyle to DropDownList, which stops the user from entering a value. However, now I can't use the Auto-Complete feature, which requires user input. Is there another way to limit input to the list, while still allowing use of the Auto-Complete feature? Note that I have seen some custom solutions for this, but I really like the way the matching Auto-Complete items are displayed in a Drop-Down list, and sorted even though the original list may not be. EDIT: I have thought about just validating the entered value, i.e. testing user input if it is valid in, say, the TextChanged event, or even using the Validating event. The question then is what is the expected behavior? Do I clear their value (an empty value is also invalid), or do I use a default value? Closest matching value? P.s. Is there any other tags that I could add to this question?

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  • Refresh page in browser without resubmitting form

    - by Michael
    I'm an ASP.NET developer, and I usually find myself leaving the webpage that I'm working on open in my browser (Chrome is my browser of choice, but this question is relevant for any browser). My workflow typically goes like this: I write code, I rebuild my project in Visual Studio, and then I flip back to my browser with Alt-Tab and hit F5 to refresh the page. This is fine and dandy if a form hasn't been submitted since the page was opened. But if I've been clicking around on ASP.NET form controls, the page has posted form data a number of times, so hitting F5 causes the browser to (sensibly) pop up a confirmation message, e.g., "Confirm Form Resubmission: The page that you're looking for used information that you entered...". Sometimes I do want to resubmit the form, but more often than not, I just want to start over with the page (rather than resubmit form data). The way I usually get around this is to simply add some query string data to the URL so that the browser sees it as a fresh page request, e.g.: page.aspx becomes page.aspx? (or vice-versa). My question is: Is there a better way to quickly request a fresh version of a webpage (and not submit form data) in any of the major browsers? It seems like a no-brainer to me for web development, but maybe I'm missing something. What I'd love to see is something like the last item in this list: F5: refresh page Ctrl-F5: refresh page (and force cache refresh) Alt-F5: request fresh copy of the page without resubmitting the form

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  • Java Days & Bookings

    - by sys_debug
    Ok this is an extension of a question I asked about earlier yet this is the next step that is unclear to me. Everything else will be ready and this part is driving me mad! some members provided great help and I already made progress with that info, but this is just another obstacle. I am creating a booking object (as was suggested) that will have a start date and end date. each booking will also have a number of seats associated with it (that I require to reserve). The total available number of seats any given day 46 (as the total capacity of the hall is 46 seats). so in assumption that I have a booking to be made in the system, and start date is 1st jan and end date is 10th jan. The question is how can I check the remaining seats in all those days between the range to see if requested number could be hosted or not? and then when the second booking is made, it will have to see that the days in this range already have less than 46 and decrement further if possible to host the reservation. one of the members, and I appreciate his effort, gladly contributed a method to compare if this booking is after or before the existing bookings. The code provided is here: public boolean overlapsWithExisting(Booking booking) { final Date early = booking.getStart(); final Date late = booking.getEnd(); for(Booking existing : existingBookings) { if(!(early.isAfter(existing.getEnd() || late.isBefore(existing.getStart())) return true; } return false; } I just want to know how to associate 46 with each day and keep record of days that are decremented by bookings. Thanks and reallllllly appreciated :D

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  • Displaying cookies as key=value for all domains?

    - by OverTheRainbow
    Hello, This question pertains to the use of the cookie-capable WebClient derived class presented in the How can I get the WebClient to use Cookies? question. I'd like to use a ListBox to... 1) display each cookie individually as "key=value" (the For Each loop displays all of them as one string), and 2) be able to display all cookies, regardless of the domain from which they came ("www.google.com", here): Imports System.IO Imports System.Net Public Class Form1 Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click Dim webClient As New CookieAwareWebClient Const URL = "http://www.google.com" Dim response As String response = webClient.DownloadString(URL) RichTextBox1.Text = response 'How to display cookies as key/value in ListBox? 'PREF=ID=5e770c1a9f279d5f:TM=1274032511:LM=1274032511:S=1RDPaKJKpoMT9T54 For Each mycc In webClient.cc.GetCookies(New Uri(URL)) ListBox1.Items.Add(mycc.ToString) Next End Sub End Class Public Class CookieAwareWebClient Inherits WebClient Public cc As New CookieContainer() Private lastPage As String Protected Overrides Function GetWebRequest(ByVal address As System.Uri) As System.Net.WebRequest Dim R = MyBase.GetWebRequest(address) If TypeOf R Is HttpWebRequest Then With DirectCast(R, HttpWebRequest) .CookieContainer = cc If Not lastPage Is Nothing Then .Referer = lastPage End If End With End If lastPage = address.ToString() Return R End Function End Class Thank you.

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  • What prevents a user from adding controls to an ASP.NET page client side?

    - by Curtis White
    This goes back to my other question which I thought was sufficiently answers but upon reflect am not sure that it was (sorry). Backgrounder: I am generating a form dynamically. I am pulling from the database the controls. I must associate each control with a database ID which is not the user's session id. I do this currently by storing my ID in the ID for the web control with some other stuff to make it unique/clear what I am doing. On the post back, I iterate through all the controls on my web page checking for my special identifier, ie, MyGeneratedTextBox_ID_Unique. This process enables for 2 important steps, identifying the control was one I generated and also getting the ID for this input field. And, all of this works but I'm still concerned about the security of it. I do not see a security issue with showing the actual database ID's in this case, although agree it is not desirable. However, I am concerned of the following possibilities: If a user could add a nefarious control to my collection and use that for a SQL injection attack. More academic, but if a user could somehow store data for fields they do not have access too by changing the id's. I agree this is a "hack" of a way to do it. But my question is, is it a security risk and is there an 'easy' way to do it in a less hack way? I assume that only the controls that are created/instantiated on the page are added to the controls list.. thus all controls must be created server side and thus the security issue is address but just wanted to validate. Thanks again. PS: I could see adding a property for each control and encrypting the viewstate would be a little more secure.

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  • Objective-C Definedness

    - by Dan Ray
    This is an agonizingly rookie question, but here I am learning a new language and framework, and I'm trying to answer the question "What is Truth?" as pertains to Obj-C. I'm trying to lazy-load images across the network. I have a data class called Event that has properties including: @property (nonatomic, retain) UIImage image; @property (nonatomic, retain) UIImage thumbnail; in my AppDelegate, I fetch up a bunch of data about my events (this is an app that shows local arts event listings), and pre-sets each event.image to my default "no-image.png". Then in the UITableViewController where I view these things, I do: if (thisEvent.image == NULL) { NSLog(@"Going for this item's image"); UIImage *tempImage = [UIImage imageWithData:[NSData dataWithContentsOfURL: [NSURL URLWithString: [NSString stringWithFormat: @"http://www.mysite.com/content_elements/%@_image_1.jpg", thisEvent.guid]]]]; thisEvent.image = tempImage; } We never get that NSLog call. Testing thisEvent.image for NULLness isn't the thing. I've tried == nil as well, but that also doesn't work.

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  • Is there a way to specify a per-host deploy_to path with Capistrano?

    - by Chad Johnson
    I have searched and searched and asked a question already and have not received a clear answer. I have the following deploy script (snippet): set :application, "testapplication" set :repository, "ssh://domain.com//srv/hg/#{application}" set :scm, :mercurial set :deploy_to, "/srv/www/#{application}" role :web, "domain1.com", "domain2.com" role :app, "domain1.com", "domain2.com" role :db, "domain1.com", :primary => true, :norelease => true role :db, "domain2.com", :norelease => true As you see, I have set deploy_to to a specific path. And, I also have specified multiple web servers. However, each web server should have a different deployment path. I want to be able to run "cap deploy" and deploy to all hosts in one shot. I am NOT trying to deploy to staging and then to production. This is all production. My question is: how exactly do I specify a path per server? I have read the "Roles" documentation for Capistrano, and this is unclear. Can someone please post a deploy file example? I have read the documentation, and it is unclear how to do this. Does anyone know? Am I crazy? Am I thinking of this wrong or something? No answers anywhere online. Nowhere. Nothing. Please, someone help.

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  • odd url, and difficulty in following the php page flow

    - by sdfor
    I'm trying to understand code that I bought so I can modify it. In the index.php there are picture links: <a href="test10,10"><img title="" border=1 src="makethumb.php?pic=product_images/test101.jpg&amp;w=121&amp;sq=N" / ></a> I don't understand the href since it is not pointing to a page. test10 is an id of a picture. I assumed it was going back to the index.php and the code would extract the test10,10 from the url, but it's not. I know that because I put in trace code as the first line. The question is, where is the link going to? I know it that it somewhere in the process it executes a page called profile.php, but nowhere in the source code (doing a global search) is there an explicit call to profile.php. As a related question, is there a way to profile the code to see what pages it's calling without using xdebug, which for the life of me I can't get working after many hours of trying every suggestion I found here and else where. (I'm using xampp) thanks

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  • Log session and session changes of a asp.net web user

    - by Johan Wikström
    This is going to be a quite broad question, and any suggestions, examples, links are very welcome! I'm looking for a good way to log my users session, and actions on the site up to a certain point. The site in question is a site for doing bookings. The users start with doing a search, doing a few steps of data gathering and selections and end up with a booking. So what I need to implement is some kind of logging of the current session variables at each step the user takes. And perhaps some other valid information. Logging should preferably be done to the a database. At the end i would like to associate all these session with a booking reference. The goal is to later if something goes wrong with the booking or we need to investigate a situation have all information we need. I understand log4net is a popular choice for logging, and used it a bit myself for simple purposes, but can not find any good examples regarding my situation. This should be a common situation, i'm curious how others do it.

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  • JDO architecture: One to many relationship and cascading deleting

    - by user361897
    I’m new to object oriented database designs and I’m trying to understand how I should be structuring my classes in JDO for google app engine, particularly one to many relationships. Let’s say I’m building a structure for a department store where there are many departments, and each department has many products. So I’d want to have a class called Department, with a variable that is a list of a Product class. @PersistenceCapable public class Department { @PrimaryKey @Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY) private String deptID; @Persistent private String departmentName; @Persistent private List<Product>; } @PersistenceCapable public class Product { @PrimaryKey @Persistent(valueStrategy = IdGeneratorStrategy.IDENTITY) private String productID; @Persistent private String productName; } But one Product can be in more than one Department (like a battery could be in electronics and household supplies). So the next question is, how do I not duplicate data in the OOD world and have only one copy of product data in numerous departments? And the next question is, let’s say I delete out a particular product, how do each of the departments know it was deleted?

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  • Why do people keep parsing HTML using regex? [closed]

    - by polygenelubricants
    As much as I love regular expressions, it's obvious to me that it's not the best tool for parsing HTML, especially given the numerous good HTML parsers out there. And yet there are numerous questions on stackoverflow that attempts to parse HTML using regex. And people would always point out what a bad idea that is in the comments. And the accepted answer would often have a disclaimer how this isn't really the ideal way of doing things. But based on the constant flow of questions, it still seems that people keep parsing HTML using regex, despite the perceived difficulty in reading and maintaining it (and that's putting correctness aside for now). So my question is: why? Is it because it's easy to learn? Is it because it's faster? Is it because it's the industry standard? Is it because there are already so many reusable regexes to build from? Is it because 100% correctness is never really the objective? (90% good enough?) etc... I'd also like to hear from the downvoters why they did so. Is it because: There's absolutely nothing wrong with using regex to parse HTML and asking "Why?" is just dumb? The premise of the question is flawed because the people who are using regex to parse HTML is such a small minority?

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  • Are Thread.stop and friends ever safe in Java?

    - by Stephen C
    The stop(), suspend(), and resume() in java.lang.Thread are deprecated because they are unsafe. The Sun recommended work around is to use Thread.interrupt(), but that approach doesn't work in all cases. For example, if you are call a library method that doesn't explicitly or implicitly check the interrupted flag, you have no choice but to wait for the call to finish. So, I'm wondering if it is possible to characterize situations where it is (provably) safe to call stop() on a Thread. For example, would it be safe to stop() a thread that did nothing but call find(...) or match(...) on a java.util.regex.Matcher? (If there are any Sun engineers reading this ... a definitive answer would be really appreciated.) EDIT: Answers that simply restate the mantra that you should not call stop() because it is deprecated, unsafe, whatever are missing the point of this question. I know that that it is genuinely unsafe in the majority of cases, and that if there is a viable alternative you should always use that instead. This question is about the subset cases where it is safe. Specifically, what is that subset?

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