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  • How can I bind a simple Javascript array to an MVC3 controller action method?

    - by Sergio Tapia
    Here is the javascript code I use to create the array and send it on it's way: <script type="text/javascript" language="javascript"> $(document).ready(function () { $("#update-cart-btn").click(function() { var items = []; $(".item").each(function () { var productKey = $(this).find("input[name='item.ProductId']").val(); var productQuantity = $(this).find("input[type='text']").val(); items[productKey] = productQuantity; }); $.ajax({ type: "POST", url: "@Url.Action("UpdateCart", "Cart")", data: items, success: function () { alert("Successfully updated your cart!"); } }); }); }); </script> The items object is properly constructed with the values I need. What data type must my object be on the backend of my controller? I tried this but the variable remains null and is not bound. [Authorize] [HttpPost] public ActionResult UpdateCart(object[] items) // items remains null. { // Some magic here. return RedirectToAction("Index"); }

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  • Entity Framework 4 and SQL Compact 4: How to generate database?

    - by David Veeneman
    I am developing an app with Entity Framework 4 and SQL Compact 4, using a Model First approach. I have created my EDM, and now I want to generate a SQL Compact 4.0 database to act as a data store for the model. I bring up the Generate Database Wizard and click the New Connection button to create a connection for the generated file. The Choose Data Source dialog appears, but SQL Compact 4.0 is not listed in the list of available data sources: I am running VS 2010 SP1 (beta) and I have installed the VS 2010 Tools for SQL Compact 4.0. I can create a SQL Compact 4.0 data connection from the Server Explorer. It is only in the Generate Database Wizard that the 4.0 option doesn't appear. BTW, my SQL Compact 4.0 installation does include System.Data.SqlServerCe.Entity.dll. So I should have the SQL Compact components I need. Am I doing something incorrectly, or is this a bug? Does anyone have a fix or a workaround? Thanks for your help.

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  • Put together tiles in android sdk and use as background

    - by Jon
    In a feeble attempt to learn some Android development am I stuck at graphics. My aim here is pretty simple: Take n small images and build a random image, larger than the screen with possibility to scroll around. Have an animated object move around on it I have looked at the SDK examples, Lunar Lander especially but there are a few things I utterly fail to wrap my head around. I've got a birds view plan (which in my head seems reasonably sane): How do I merge the tiles into one large image? The background is static so I figure I should do like this: Make a 2d array with refs to the tiles Make a large Drawable and draw the tiles on it At init draw this big image as the background At each onDraw redraw the background of the previous spot of the moving object, and the moving object at its new location The problem is the hands on things. I load the small images with "Bitmap img1 = BitmapFactory.decodeResource (res, R.drawable.img1)", but then what? Should I make a canvas and draw the images on it with "canvas.drawBitmap (img1, x, y, null);"? If so how to get a Drawable/Bitmap from that? I'm totally lost here, and would really appreciate some hands on help (I would of course be grateful for general hints as well, but I'm primarily trying to understand the Graphics objects). To make you, dear reader, see my level of confusion will I add my last desperate try: Drawable drawable; Canvas canvas = new Canvas (); Bitmap img1 = BitmapFactory.decodeResource (res, R.drawable.img1); // 50 x 100 px image Bitmap img2 = BitmapFactory.decodeResource (res, R.drawable.img2); // 50 x 100 px image canvas.drawBitmap (img1, 0, 0, null); canvas.drawBitmap (img2, 50, 0, null); drawable.draw (canvas); // obviously wrong as draw == null this.setBackground (drawable); Thanks in advance

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  • @attribute elements in XML

    - by danit
    Here is my XML: ["link"]=> array(2) { [0]=> object(SimpleXMLElement)#244 (1) { ["@attributes"]=> array(3) { ["type"]=> string(9) "text/html" ["href"]=> string(48) "http://twitter.com/MoodleDan/statuses/1226112723" ["rel"]=> string(9) "alternate" } } [1]=> object(SimpleXMLElement)#245 (1) { ["@attributes"]=> array(3) { ["type"]=> string(9) "image/png" ["href"]=> string(59) "http://a3.twimg.com/profile_images/226895523/Dan_normal.png" ["rel"]=> string(5) "image" } } } ["author"]=> object(SimpleXMLElement)#246 (2) { ["name"]=> string(14) "Dan Humpherson" ["uri"]=> string(16) "http://vl3.co.uk" } The above XML is part of a larger array, but how do i get the href -> ["href"]=> string(59) "http://a3.twimg.com/profile_images/226895523/Dan_normal.png" Element to echo in PHP? This is what I tried (Wrong I know) foreach ($entry->link as $img) { echo $img->href; echo "<img src='". $img ."' />"; }

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  • Django: DatabaseError column does not exist

    - by Rosarch
    I'm having a problem with Django 1.2.4. Here is a model: class Foo(models.Model): # ... ftw = models.CharField(blank=True) bar = models.ForeignKey(Bar) Right after flushing the database, I use the shell: Python 2.6.6 (r266:84292, Sep 15 2010, 15:52:39) [GCC 4.4.5] on linux2 Type "help", "copyright", "credits" or "license" for more information. (InteractiveConsole) >>> from apps.foo.models import Foo >>> Foo.objects.all() Traceback (most recent call last): File "<console>", line 1, in <module> File "/usr/local/lib/python2.6/dist-packages/django/db/models/query.py", line 67, in __repr__ data = list(self[:REPR_OUTPUT_SIZE + 1]) File "/usr/local/lib/python2.6/dist-packages/django/db/models/query.py", line 82, in __len__ self._result_cache.extend(list(self._iter)) File "/usr/local/lib/python2.6/dist-packages/django/db/models/query.py", line 271, in iterator for row in compiler.results_iter(): File "/usr/local/lib/python2.6/dist-packages/django/db/models/sql/compiler.py", line 677, in results_iter for rows in self.execute_sql(MULTI): File "/usr/local/lib/python2.6/dist-packages/django/db/models/sql/compiler.py", line 732, in execute_sql cursor.execute(sql, params) File "/usr/local/lib/python2.6/dist-packages/django/db/backends/util.py", line 15, in execute return self.cursor.execute(sql, params) File "/usr/local/lib/python2.6/dist-packages/django/db/backends/postgresql_psycopg2/base.py", line 44, in execute return self.cursor.execute(query, args) DatabaseError: column foo_foo.bar_id does not exist LINE 1: ...t_omg", "foo_foo"."ftw", "foo_foo... What am I doing wrong here?

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  • Comparison operators not supported for type IList when Paging data in Linq to Sql

    - by Dan
    I can understand what the error is saying - it can't compare a list. Not a problem, other than the fact that I don't know how to not have it compare a list when I want to page through a model with a list as a property. My Model: Event : IEvent int Id string Title // Other stuff.. LazyList<EventDate> Dates // The "problem" property Method which pages the data (truncated): public JsonResult JsonEventList(int skip, int take) { var query = _eventService.GetEvents(); // Do some filtering, then page data.. query = query.Skip(skip).Take(take); return Json(query.ToArray()); } As I said, the above is truncated quite a bit, leaving only the main point of the function: filter, page and return JSON'd data. The exception occurs when I enumerate (.ToArray()). The Event object is really only used to list the common objects of all the event types (Meetings, Birthdays, etc - for example). It still implements IEvent like the other types, so I can't just remove the LazyList<EventDate> Dates' property unless I no longer implementIEvent` Anyway, is there a way to avoid this? I don't really want to compare a LazyList when I page, but I do not know how to resolve this issue. Thank you in advance! :)

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  • Membership.Updateuser not really updating the database.

    - by Shimrod
    Hi everybody, I'm currently working on a membership system for my web application, which is based on forms authentication from the framework. I created some users with the integrated tool, and the login is perfectly working. But now what I want to do is to give administrator the capability to create, modify, delete users. So here is what I've got right now: Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load Dim muc As MembershipUserCollection = Membership.GetAllUsers() ComboBox1.DataSource = muc ComboBox1.DataValueField = "UserName" ComboBox1.DataTextField = "UserName" ComboBox1.DataBind() End Sub Protected Sub ComboBox1_SelectedIndexChanged(ByVal sender As Object, ByVal e As EventArgs) Handles ComboBox1.SelectedIndexChanged Dim userName As String = ComboBox1.SelectedValue Dim mu As MembershipUser = Membership.GetUser(userName) Dim userRoles As String() = Roles.GetRolesForUser(userName) tbComments.Text = mu.Comment tbEmail.Text = mu.Email lblUserName.Text = mu.UserName End Sub Protected Sub Button1_Click(ByVal sender As Object, ByVal e As EventArgs) Handles Button1.Click Dim userName As String = ComboBox1.SelectedValue Dim mu As MembershipUser = Membership.GetUser(userName) If Not mu Is Nothing Then Try mu.Comment = tbComments.Text Membership.UpdateUser(mu) mu.Email = tbEmail.Text Membership.UpdateUser(mu) mu.IsApproved = True Membership.UpdateUser(mu) mu = Nothing Catch ex As Exception Console.WriteLine(ex.ToString()) End Try End If DetailPanel.Visible = False End Sub The problem is that the record doesn't seem to be updated in the database. I made the multiple calls to Membership.UpdateUser after reading this blog entry, but it didn't change anything. A strange think I noticed while debugging, is that when I enter the Button1_Click method, Membership.GetUser(userName) returns me values from my precedent attempt ! I don't really understand what I'm missing. Does someone have a clue ? Thanks in advance !

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  • Using django and django-voting app, how can I order a queryset according to the votes of each item?

    - by snz3
    (I'm new to python and django so please bear with me for a second. I apologise if this has been answered elsewhere and couldn't find it) Let's say I have a Link model and through the django-voting application users can vote on link instances. How can I order those link instances according to their score, eg. display those with the higher score first. I assume I could use the get_top manager of django-voting, but that would only give me the top scoring link instances and wouldn't take into consideration other parameters I would like to add (for example, those links that belong to a specific user or paging or whatever). My guess would be to write a custom manager for my Link model where by I can filter a queryset according to each item's score. If I understand correctly that will require me to loop through each item, check its score, and then place it a list (or dictionary) which will then be sorted according to the score of each item. That wouldn't return a queryset but a dictionary with each item. Am I missing something here?

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  • Getting around IBActions limited scope

    - by Septih
    Hello, I have an NSCollectionView and the view is an NSBox with a label and an NSButton. I want a double click or a click of the NSButton to tell the controller to perform an action with the represented object of the NSCollectionViewItem. The Item View is has been subclassed, the code is as follows: #import <Cocoa/Cocoa.h> #import "WizardItem.h" @interface WizardItemView : NSBox { id delegate; IBOutlet NSCollectionViewItem * viewItem; WizardItem * wizardItem; } @property(readwrite,retain) WizardItem * wizardItem; @property(readwrite,retain) id delegate; -(IBAction)start:(id)sender; @end #import "WizardItemView.h" @implementation WizardItemView @synthesize wizardItem, delegate; -(void)awakeFromNib { [self bind:@"wizardItem" toObject:viewItem withKeyPath:@"representedObject" options:nil]; } -(void)mouseDown:(NSEvent *)event { [super mouseDown:event]; if([event clickCount] > 1) { [delegate performAction:[wizardItem action]]; } } -(IBAction)start:(id)sender { [delegate performAction:[wizardItem action]]; } @end The problem I've run into is that as an IBAction, the only things in the scope of -start are the things that have been bound in IB, so delegate and viewItem. This means that I cannot get at the represented object to send it to the delegate. Is there a way around this limited scope or a better way or getting hold of the represented object? Thanks.

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  • Set .aspx page title to that of an Eval

    - by user1860529
    I am trying to use an <%# Eval("name") %> to be the title of my page. I can't seem to figure out any solutions online. I have tried the other StackOverflow question but that did now work either. The page is a bio.aspx and on the site it is displayed as bio.aspx?id=123 so the page title needs to vary depending on the ID. I figured I could just use the Eval("name") but no luck yet. I currently am using JavaScript: window.onload = function() { document.title = '<%# Eval("name") %> | Title Line'; } This works, but it still leaves the title tags empty, and it's kind of spammy. Here is the codebehind: using System; using System.Data; using System.Configuration; using System.Collections; using System.Web; using System.Web.Security; using System.Web.UI; using System.Web.UI.WebControls; using System.Web.UI.WebControls.WebParts; using System.Web.UI.HtmlControls; public partial class DoctorBio : System.Web.UI.Page { protected void Page_Load(object sender, EventArgs e) { Page.Title = "Your Page Title"; HtmlMeta metaDescription = new HtmlMeta(); metaDescription.Name = "description"; metaDescription.Content = "brief description"; Page.Header.Controls.Add(metaDescription); HtmlMeta metaKeywords = new HtmlMeta(); metaKeywords.Name = "keywords"; metaKeywords.Content = "keywords, keywords"; Page.Header.Controls.Add(metaKeywords); } protected void SetPageTitle(object title) { this.Title = title.ToString(); } protected string ReplaceLineBreaks(object text) { string newText = text as string; if (newText == null) { return string.Empty; } return newText.Replace("\r\n", "<br />"); } }

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  • Rails rake test returns an error message

    - by eakkas
    I am a rails newbie and receive the following message when I run rake test. This is a an application based on rails community engine. I tried creating a test application just to make sure that my gems etc. are fine and I am able to run rake test successfully in that application. It would be great if someone could shed a light on what is going wrong... /usr/lib/ruby/gems/1.8/gems/activesupport-2.3.5/lib/active_support/whiny_nil.rb:52:in `method_missing': undefined method `merge' for nil:NilClass (NoMethodError) from /home/eakkas/NetBeansProjects/hello_ce/vendor/plugins/community_engine/app/controllers/users_controller.rb:17 from /usr/local/lib/site_ruby/1.8/rubygems/custom_require.rb:31:in `gem_original_require' from /usr/local/lib/site_ruby/1.8/rubygems/custom_require.rb:31:in `require' from /usr/lib/ruby/gems/1.8/gems/activesupport-2.3.5/lib/active_support/dependencies.rb:158:in `require_without_desert' from /usr/lib/ruby/gems/1.8/gems/desert-0.5.3/lib/desert/ruby/object.rb:8:in `require' from /usr/lib/ruby/gems/1.8/gems/desert-0.5.3/lib/desert/ruby/object.rb:32:in `__each_matching_file' from /usr/lib/ruby/gems/1.8/gems/desert-0.5.3/lib/desert/ruby/object.rb:7:in `require' from /usr/lib/ruby/gems/1.8/gems/activesupport-2.3.5/lib/active_support/dependencies.rb:265:in `require_or_load' from /usr/lib/ruby/gems/1.8/gems/desert-0.5.3/lib/desert/rails/dependencies.rb:27:in `depend_on' from /usr/lib/ruby/gems/1.8/gems/desert-0.5.3/lib/desert/rails/dependencies.rb:26:in `each' from /usr/lib/ruby/gems/1.8/gems/desert-0.5.3/lib/desert/rails/dependencies.rb:26:in `depend_on' from /usr/lib/ruby/gems/1.8/gems/activesupport-2.3.5/lib/active_support/dependencies.rb:136:in `require_dependency' from /usr/lib/ruby/gems/1.8/gems/rails-2.3.5/lib/initializer.rb:414:in `load_application_classes' from /usr/lib/ruby/gems/1.8/gems/rails-2.3.5/lib/initializer.rb:413:in `each' from /usr/lib/ruby/gems/1.8/gems/rails-2.3.5/lib/initializer.rb:413:in `load_application_classes' from /usr/lib/ruby/gems/1.8/gems/rails-2.3.5/lib/initializer.rb:411:in `each' from /usr/lib/ruby/gems/1.8/gems/rails-2.3.5/lib/initializer.rb:411:in `load_application_classes' from /usr/lib/ruby/gems/1.8/gems/rails-2.3.5/lib/initializer.rb:197:in `process' from /usr/lib/ruby/gems/1.8/gems/rails-2.3.5/lib/initializer.rb:113:in `send' from /usr/lib/ruby/gems/1.8/gems/rails-2.3.5/lib/initializer.rb:113:in `run'

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  • Implementation of delegates in C#

    - by Ram
    Hi, I am trying to learn on how to use delegates efficiently in C# and I was just wondering if anyone can guide me through... The following is a sample implementation using delegates... All I am doing is just passing a value through a delegate from one class to another... Please tell me if this is the right way to implement... And also your suggestions... Also, please note that I have de-registered the delegate in : void FrmSample_FormClosing(object sender, FormClosingEventArgs e) { sampleObj.AssignValue -= new Sample.AssignValueDelegate(AssignValue); } Is this de-registration necessary? The following is the code that I have written.. public partial class FrmSample : Form { Sample sampleObj; public FrmSample() { InitializeComponent(); this.Load += new EventHandler(FrmSample_Load); this.FormClosing += new FormClosingEventHandler(FrmSample_FormClosing); sampleObj = new Sample(); sampleObj.AssignValue = new Sample.AssignValueDelegate(AssignValue); } void FrmSample_FormClosing(object sender, FormClosingEventArgs e) { sampleObj.AssignValue -= new Sample.AssignValueDelegate(AssignValue); } void FrmSample_Load(object sender, EventArgs e) { sampleObj.LoadValue(); } void AssignValue(string value) { MessageBox.Show(value); } } class Sample { public delegate void AssignValueDelegate(string value); public AssignValueDelegate AssignValue; internal void LoadValue() { if (AssignValue != null) { AssignValue("This is a test message"); } } } Pls provide your feedback on whether this is right... Thanks, Ram

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  • Keeping dates in order when using date_select and discarding year in Rails?

    - by MikeH
    My app has users who have seasonal products. When a user selects a product, we allow him to also select the product's season. We accomplish this by letting him select a start date and an end date for each product. We're using date_select to generate two sets of drop-downs: one for the start date and one for the end date. Including years doesn't make sense for our model. So we're using the option: discard_year => true To explain our problem, consider that our products are apples. Vendor X carries apples every year from September to January. Years are irrelevant here, and that's why we're using discard_year => true. However, while the specific years are irrelevant, the relative point in time from the start date to the end date is relevant. This is where our problem arises. When you use discard_year => true, Rails does set a year in the database, it just doesn't appear in the views. Rails sets all the years to 0001 in our app. Going back to our apple example, this means that the database now thinks the user has selected September 0001 to January 0001. This is a problem for us for a number of reasons. To solve this, the logic that I need to implement is the following: - If season_start month/date is before season_end month/date, then standard Rails approach is fine. - But, if season_start month/date is AFTER season_end month/date, then I need to dynamically update the database field such that the year for season_end is equal to the year for season_start + 1. My best guess is that I would create a custom method that runs as an after_save or after_update in my products model. But I'm not really sure how to do this. Ideas? Anybody ever had this issue? Thanks!

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  • Easiest way to specify the selected option to a dropdown list in ASP.NET MVC

    - by sdr
    I have a list of options (IEnumerable< SelectListItem ) in my model that I want to use in multiple dropdowns in my view. But each of these dropdowns could have a different selected option. Is there an easy way to simply specfiy which should be selected if using the Html.DropDownList helper? At this point, the only way I can see is to generate the html myself and loop through the list of options like so: <% for(int i=0; i<10; i++) { %> <select name="myDropDown<%= i %>"> <% foreach(var option in Model.Options) { %> <option value="<%= Html.Encode(option.optValue) %>" <%if(ShouldBeSelected(i)) {%> selected="selected"<% } %>><%= Html.Encode(option.optText) %></option> <% } %> </select> <% } %>

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  • Silverlight Data Binding for Collection in Stack Panel

    - by Blake Blackwell
    I'm new to Silverlight, so I don't have a complete grasp of all the controls at my disposal. What I would like to do is use databinding and a view model to maintain a collection of items. Here is some mock code for what I'd like to do: Model public class MyItem { public string DisplayText { get; set; } public bool Enabled { get; set; } } ViewModel public class MyViewModel : INotifyPropertyChanged { private ObservableCollection<MyItem> _myItems = new ObservableCollection<MyItem>(); public ObservableCollection<MyItem> MyItems { get { return _myItems; } set { _myItems = value NotifyPropertyChanged(this, "MyItems"); } } } View <Grid x:Name="LayoutRoot" Background="White"> <StackPanel ItemsSource="{Binding MyItems}"> <StackPanel Orientation="Horizontal"> <CheckBox "{Binding Enabled, Mode=TwoWay}"></CheckBox> <TextBlock Text="{Binding DisplayText, Mode=TwoWay}" /> </StackPanel> </StackPanel> </Grid> So my end goal would be that every time I add another MyItem to the MyItems collection it would create a new StackPanel with checkbox and textblock. I don't have to use a stack panel but just thought I'd use that for this sample.

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  • Visual Studio crashes consistently on web-related projects

    - by Traveling Tech Guy
    Hi, I have a brand new VS2010 installed on a Win2008R2 machine. I started getting this error when debugging a WCF service project: "Attempted to read or write protected memory. This is often an indication that other memory is corrupt." When I started developing a web site a week later, this became consistent - I can't debug it. The stack dump reads: at Microsoft.VisualStudio.WebHost.Host.ProcessRequest(Connection conn) at Microsoft.VisualStudio.WebHost.Server.OnSocketAccept(Object acceptedSocket) at System.Threading.QueueUserWorkItemCallback.WaitCallback_Context(Object state) at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean ignoreSyncCtx) at System.Threading.QueueUserWorkItemCallback.System.Threading.IThreadPoolWorkItem.ExecuteWorkItem() at System.Threading.ThreadPoolWorkQueue.Dispatch() at System.Threading._ThreadPoolWaitCallback.PerformWaitCallback() I tried searching online, and some recommend turning off the "Suppress JIT Optimizations" in the Debugging options - this dos not seem to make a difference. Clearly the problem is with the built in web server. But am I doing something wrong? Is there something I can do? Or is this a known bug? Thanks for your time, Guy Update 12/31: Today I tried using CassiniDev as a replacement to the original VS2010 WebServer - exact same result. My suspicion is that there's some internal conflict between VS2010, Windows Server 2008R2 and maybe the fact that it's a 64 bit OS. I switched to using IIS as my debug server - and that seems to work, with some annoying side effects. My conclusion: do not use a 64 bit server system as your dev machine. Develop on 32bit - deploy to 64bit. Side conclusion: there are some scenarios Microsoft's QA doesn't test.

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  • Force sending a user to custom QuerySet.

    - by Jack M.
    I'm trying to secure an application so that users can only see objects which are assigned to them. I've got a custom QuerySet which works for this, but I'm trying to find a way to force the use of this additional functionality. Here is my Model: class Inquiry(models.Model): ts = models.DateTimeField(auto_now_add=True) assigned_to_user = models.ForeignKey(User, blank=True, null=True, related_name="assigned_inquiries") objects = CustomQuerySetManager() class QuerySet(QuerySet): def for_user(self, user): return self.filter(assigned_to_user=user) (The CustomQuerySetManager is documented over here, if it is important.) I'm trying to force everything to use this filtering, so that other methods will raise an exception. For example: Inquiry.objects.all() ## Should raise an exception. Inquiry.objects.filter(pk=69) ## Should raise an exception. Inquiry.objects.for_user(request.user).filter(pk=69) ## Should work. inqs = Inquiry.objects.for_user(request.user) ## Should work. inqs.filter(pk=69) ## Should work. It seems to me that there should be a way to force the security of these objects by allowing only certain users to access them. I am not concerned with how this might impact the admin interface.

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  • Implementing list position locator in C++?

    - by jfrazier
    I am writing a basic Graph API in C++ (I know libraries already exist, but I am doing it for the practice/experience). The structure is basically that of an adjacency list representation. So there are Vertex objects and Edge objects, and the Graph class contains: list<Vertex *> vertexList list<Edge *> edgeList Each Edge object has two Vertex* members representing its endpoints, and each Vertex object has a list of Edge* members representing the edges incident to the Vertex. All this is quite standard, but here is my problem. I want to be able to implement deletion of Edges and Vertices in constant time, so for example each Vertex object should have a Locator member that points to the position of its Vertex* in the vertexList. The way I first implemented this was by saving a list::iterator, as follows: vertexList.push_back(v); v->locator = --vertexList.end(); Then if I need to delete this vertex later, then rather than searching the whole vertexList for its pointer, I can call: vertexList.erase(v->locator); This works fine at first, but it seems that if enough changes (deletions) are made to the list, the iterators will become out-of-date and I get all sorts of iterator errors at runtime. This seems strange for a linked list, because it doesn't seem like you should ever need to re-allocate the remaining members of the list after deletions, but maybe the STL does this to optimize by keeping memory somewhat contiguous? In any case, I would appreciate it if anyone has any insight as to why this happens. Is there a standard way in C++ to implement a locator that will keep track of an element's position in a list without becoming obsolete? Much thanks, Jeff

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  • SQLAlchemy: who is in charge of the "session"? ( and how to unit-test with sessions )

    - by Nick Perkins
    I need some guidance on how to use session objects with SQLAlchemy, and how to organize Unit Tests of my mapped objects. What I would like to able to do is something like this: thing = BigThing() # mapped object child = thing.new_child() # create and return a related object thing.save() # will also save the child object In order to achieve this, I was thinking of having the BigThing actually add itself ( and it's children ) to the database -- but maybe this not a good idea? One reason to add objects as soon as possible is Automatic id values that are assigned by the database -- the sooner they are available, the fewer problems there are ( right? ) What is the best way to manage session objects? Who is in charge of the session? Should it be created only when required? or saved for a long time? What about Unit Tests for my mapped objects?...how should the session be handled? Is it ever OK to have mapped objects just automatically add themselves to a database? or is that going to lead to trouble?

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  • systematizing error codes for a web app in php?

    - by user151841
    I'm working on a class-based php web app. I have some places where objects are interacting, and I have certain situations where I'm using error codes to communicate to the end user -- typically when form values are missing or invalid. These are situations where exceptions are unwarranted ( and I'm not sure I could avoid the situations with exceptions anyways). In one object, I have some 20 code numbers, each of which correspond to a user-facing message, and a admin/developer-facing message, so both parties know what's going on. Now that I've worked over the code several times, I find that it's difficult to quickly figure out what code numbers in the series I've already used, so I accidentally create conflicting code numbers. For instance, I just did that today with 12, 13, 14 and 15. How can I better organize this so I don't create conflicting error codes? Should I create one singleton class, errorCodes, that has a master list of all error codes for all classes, systematizing them across the whole web app? Or should each object have its own set of error codes, when appropriate, and I just keep a list in the commentary of the object, to use and update that as I go along?

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  • Why isn't the Cache invalidated after table update using the SqlCacheDependency?

    - by Jason
    I have been trying to get SqlCacheDependency working. I think I have everything set up correctly, but when I update the table, the item in the Cache isn't invalidated. Can you look at my code and see if I am missing anything? I enabled the Service Broker for the Sandbox database. I have placed the following code in the Global.asax file. I also restart IIS to make sure it is called. void Application_Start(object sender, EventArgs e) { SqlDependency.Start(ConfigurationManager.ConnectionStrings["SandboxConnectionString"].ConnectionString); } I have placed this entry in the web.config file: <system.web> <caching> <sqlCacheDependency enabled="true" pollTime="10000"> <databases> <add name="Sandbox" connectionStringName="SandboxConnectionString"/> </databases> </sqlCacheDependency> </caching> </system.web> I call this code to put the item into the cache: protected void CacheDataSetButton_Click(object sender, EventArgs e) { using (SqlConnection sqlConnection = new SqlConnection(ConfigurationManager.ConnectionStrings["SandboxConnectionString"].ConnectionString)) { using (SqlCommand sqlCommand = new SqlCommand("SELECT PetID, Name, Breed, Age, Sex, Fixed, Microchipped FROM dbo.Pets", sqlConnection)) { using (SqlDataAdapter sqlDataAdapter = new SqlDataAdapter(sqlCommand)) { DataSet petsDataSet = new DataSet(); sqlDataAdapter.Fill(petsDataSet, "Pets"); SqlCacheDependency petsSqlCacheDependency = new SqlCacheDependency(sqlCommand); Cache.Insert("Pets", petsDataSet, petsSqlCacheDependency, DateTime.Now.AddSeconds(10), Cache.NoSlidingExpiration); } } } } Then I bind the GridView with this code: protected void BindGridViewButton_Click(object sender, EventArgs e) { if (Cache["Pets"] != null) { GridView1.DataSource = Cache["Pets"] as DataSet; GridView1.DataBind(); } } Between attempts to DataBind the GridView, I change the table's values expecting it to invalidate the Cache["Pets"] item, but it seems to stay in the Cache indefinitely.

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  • Java downcasting dilemma

    - by Shades88
    please have a look at this code here. class Vehicle { public void printSound() { System.out.print("vehicle"); } } class Car extends Vehicle { public void printSound() { System.out.print("car"); } } class Bike extends Vehicle{ public void printSound() { System.out.print("bike"); } } public class Test { public static void main(String[] args) { Vehicle v = new Car(); Bike b = (Bike)v; v.printSound(); b.printSound(); Object myObj = new String[]{"one", "two", "three"}; for (String s : (String[])myObj) System.out.print(s + "."); } } Executing this code will give ClassCastException saying inheritance.Car cannot be cast to inheritance.Bike. Now look at the line Object myObj = new String[]{"one", "two", "three"};. This line is same as Vehicle v = new Car(); right? In both lines we are assigning sub class object to super class reference variable. But downcasting String[]myObj is allowed but (Bike)v is not. Please help me understand what is going on around here.

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  • Checking instance of non-class constrained type parameter for null in generic method

    - by casperOne
    I currently have a generic method where I want to do some validation on the parameters before working on them. Specifically, if the instance of the type parameter T is a reference type, I want to check to see if it's null and throw an ArgumentNullException if it's null. Something along the lines of: // This can be a method on a generic class, it does not matter. public void DoSomething<T>(T instance) { if (instance == null) throw new ArgumentNullException("instance"); Note, I do not wish to constrain my type parameter using the class constraint. I thought I could use Marc Gravell's answer on "How do I compare a generic type to its default value?", and use the EqualityComparer<T> class like so: static void DoSomething<T>(T instance) { if (EqualityComparer<T>.Default.Equals(instance, null)) throw new ArgumentNullException("instance"); But it gives a very ambiguous error on the call to Equals: Member 'object.Equals(object, object)' cannot be accessed with an instance reference; qualify it with a type name instead How can I check an instance of T against null when T is not constrained on being a value or reference type?

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  • PHP form processing - how to capture text from field that has variable Name/ID

    - by user80151
    I have a form that has a field pulled from the database as a dropdown. I need to get the text selected in the dropdown but I don't know in advance what the field ID will be. This is basically just a form that has already been generated. I don't need to pull anything from the database, it's already on this page. All I need to do is get the form information and email it, no writing to the database. I know how to do the _Request for the other fields based on the ID but I'm not sure how to do this one. The ID changes. It can be ID=1, ID-2, etc. I need to do something like: _REQUEST form element where ID is LIKE "ID[*]" or something similar. Any suggestions or links to tutorials? Here are a couple samples of what the dropdown renders on the page: <div class="wrapperAttribsOptions"> <h4 class="optionName back"><label class="attribsSelect" for="attrib- 1">Model</label></h4> <div class="back"> <select name="id[1]" id="attrib-1"> <option value="45">VC3-4C</option> <option value="1">VC3-4PG</option> <option value="3">VC3-4SG</option> <div class="wrapperAttribsOptions"> <h4 class="optionName back"><label class="attribsSelect" for="attrib-14">SPK Model</label></h4> <div class="back"> <select name="id[14]" id="attrib-14"> <option value="43">SPK-4</option> <option value="44">SPK-8</option> </select> TIA

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  • c++ Design pattern for CoW, inherited classes, and variable shared data?

    - by krunk
    I've designed a copy-on-write base class. The class holds the default set of data needed by all children in a shared data model/CoW model. The derived classes also have data that only pertains to them, but should be CoW between other instances of that derived class. I'm looking for a clean way to implement this. If I had a base class FooInterface with shared data FooDataPrivate and a derived object FooDerived. I could create a FooDerivedDataPrivate. The underlying data structure would not effect the exposed getters/setters API, so it's not about how a user interfaces with the objects. I'm just wondering if this is a typical MO for such cases or if there's a better/cleaner way? What peeks my interest, is I see the potential of inheritance between the the private data classes. E.g. FooDerivedDataPrivate : public FooDataPrivate, but I'm not seeing a way to take advantage of that polymorphism in my derived classes. class FooDataPrivate { public: Ref ref; // atomic reference counting object int a; int b; int c; }; class FooInterface { public: // constructors and such // .... // methods are implemented to be copy on write. void setA(int val); void setB(int val); void setC(int val); // copy constructors, destructors, etc. all CoW friendly private: FooDataPrivate *data; }; class FooDerived : public FooInterface { public: FooDerived() : FooInterface() {} private: // need more shared data for FooDerived // this is the ???, how is this best done cleanly? };

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