Search Results

Search found 44956 results on 1799 pages for 'type checking'.

Page 143/1799 | < Previous Page | 139 140 141 142 143 144 145 146 147 148 149 150  | Next Page >

• The null value cannot be assigned to a member with type System.Int64 which is a non-nullable value t

  - by BritishDeveloper

  I'm getting the following error in my MVC2 app using Linq to SQL (I am new to both). I am connected to an actual SQL server not weird mdf: System.InvalidOperationException The null value cannot be assigned to a member with type System.Int64 which is a non-nullable value type My SQL table has a column called MessageID. It is BigInt type and has a primary key, NOT NULL and an IDENTITY 1 1, no Default In my dbml designer it has the following declaration for this field: [global::System.Data.Linq.Mapping.ColumnAttribute(Storage="_MessageId", AutoSync=AutoSync.OnInsert, DbType="BigInt NOT NULL IDENTITY", IsPrimaryKey=true, IsDbGenerated=true)] public long MessageId { get { return this._MessageId; } set { if ((this._MessageId != value)) { this.OnMessageIdChanging(value); this.SendPropertyChanging(); this._MessageId = value; this.SendPropertyChanged("MessageId"); this.OnMessageIdChanged(); } } } It keeps telling me that null cannot be assigned - I'm not passing through null! It's a long - it can't even be null! Am I doing something stupid? I can't find a solution anywhere! I made this work by changing the type of this property to Nullable<long> but surely this can't be right? Update: I am using InsertOnSubmit. Simplified code: public ActionResult Create(Message message) { if (ModelState.IsValid) { var db = new MessagingDataContext(); db.Messages.InsertOnSubmit(message); db.SubmitChanges(); //line 93 (where it breaks) } } breaks on SubmitChanges() with the error at the top of this question. Update2: Stack trace: at Read_Object(ObjectMaterializer`1 ) at System.Data.Linq.SqlClient.ObjectReaderCompiler.ObjectReader`2.MoveNext() at System.Linq.Enumerable.FirstOrDefault[TSource](IEnumerable`1 source) at System.Data.Linq.ChangeDirector.StandardChangeDirector.DynamicInsert(TrackedObject item) at System.Data.Linq.ChangeDirector.StandardChangeDirector.Insert(TrackedObject item) at System.Data.Linq.ChangeProcessor.SubmitChanges(ConflictMode failureMode) at System.Data.Linq.DataContext.SubmitChanges(ConflictMode failureMode) at Qanda.Controllers.MessagingController.Ask(Message message) in C:\Qanda\Qanda\Controllers\MessagingController.cs:line 93 Update3: No one knows and I don't have enough clout to offer a bounty! So continued on my ASP.NET blog. Please help!

  Read the article

• How can I get controller type and action info from a url or from route data?

  - by Rob Levine

  How can I get the controller action (method) and controller type that will be called, given the System.Web.Routing.RouteData? My scenario is this - I want to be able to do perform certain actions (or not) in the OnActionExecuting method for an action. However, I will often want to know not the current action, but the "root" action being called; by this I mean I may have a view called "Login", which is my login page. This view may include another partial view "LeftNav". When OnActionExecuting is called for LeftNav, I want to be able to determine that it is really being called for the "root" aciton of Login. I realise that by calling RouteTable.Routes.GetRouteData(actionExecutingContext.HttpContext), I can get the route for the "root" request, but how to turn this into method and type info? The only solution I have so far, is something like: var routeData = RouteTable.Routes.GetRouteData(actionExecutingContext.HttpContext) var routeController = (string)routeData.Values["controller"]; var routeAction = (string)routeData.Values["action"]; The problem with this is that "routeController" is the controller name with the "Controller" suffix removed, and is not fully qualified; ie it is "Login", rather than "MyCode.Website.LoginController". I would far rather get an actual Type and MethodInfo if possible, or at least a fully qualified type name. Any thoughts, or alternative approaches? [EDIT - this is ASP.Net MVC 1.0]

  Read the article

• Asp.net mvc 2 .net 4.0 error when View model type is Tuple with more than 4 items

  - by Bojan

  When I create strongly typed View in Asp.net mvc 2, .net 4.0 with model type Tuple I get error when Tuple have more than 4 items example 1: type of view is Tuple<string, string, string, string> (4-tuple) and everything works fine view: <%@ Page Title="" Language="C#" MasterPageFile="~/Views/Shared/WebUI.Master" Inherits="System.Web.Mvc.ViewPage<Tuple<string, string, string, string>>" %> controller: var tuple = Tuple.Create("a", "b", "c", "d"); return View(tuple); example 2: type of view is Tuple<string, string, string, string, string> (5-tuple) and I have this error: Compiler Error Message: CS1003: Syntax error, '>' expected view: <%@ Page Title="" Language="C#" MasterPageFile="~/Views/Shared/WebUI.Master" Inherits="System.Web.Mvc.ViewPage<Tuple<string, string, string, string, string>>" %> controller: var tuple = Tuple.Create("a", "b", "c", "d", "e"); return View(tuple); example 3 if my view model is of type dynamic I can use both 4-tuple and 5-tuple and there is no error on page view: <%@ Page Title="" Language="C#" MasterPageFile="~/Views/Shared/WebUI.Master" Inherits="System.Web.Mvc.ViewPage<dynamic>" %> controller: dynamic model = new ExpandoObject(); model.tuple = Tuple.Create("a", "b", "c", "d"); return View(model); or view: <%@ Page Title="" Language="C#" MasterPageFile="~/Views/Shared/WebUI.Master" Inherits="System.Web.Mvc.ViewPage<dynamic>" %> controller: dynamic model = new ExpandoObject(); model.tuple = Tuple.Create("a", "b", "c", "d", "e"); return View(model); Even if I have something like Tuple<string, Tuple<string, string, string>, string> 3-tuple and one of the items is also a tuple and sum of items in all tuples is more than 4 I get the same error, Tuple<string, Tuple<string, string>, string> works fine

  Read the article

• How do I insert data using a DetailsView into an access database without everything breaking?

  - by Steve

  Hey I'm getting the error: Data type mismatch in criteria expression. when I try to submit a DetailsView insert. Code for Default.aspx: (from inside an asp:Content tag) <asp:DetailsView ID="DetailsView1" runat="server" Height="50px" Width="125px" AutoGenerateRows="False" DataKeyNames="user_id" DataSourceID="AccessDataSource1" CellPadding="4" ForeColor="#333333" GridLines="None"> <FooterStyle BackColor="#5D7B9D" Font-Bold="True" ForeColor="White" /> <CommandRowStyle BackColor="#E2DED6" Font-Bold="True" /> <RowStyle BackColor="#F7F6F3" ForeColor="#333333" /> <FieldHeaderStyle BackColor="#E9ECF1" Font-Bold="True" /> <PagerStyle BackColor="#284775" ForeColor="White" HorizontalAlign="Center" /> <Fields> <asp:BoundField DataField="email" HeaderText="email" SortExpression="email" /> <asp:BoundField DataField="password" HeaderText="password" SortExpression="password" /> <asp:BoundField DataField="users_name" HeaderText="users_name" SortExpression="users_name" /> <asp:BoundField DataField="image_path" HeaderText="image_path" SortExpression="image_path" /> <asp:BoundField DataField="mobile" HeaderText="mobile" SortExpression="mobile" /> <asp:BoundField DataField="twitter" HeaderText="twitter" SortExpression="twitter" /> <asp:TemplateField HeaderText="privacy_level_id" SortExpression="privacy_level_id"> <InsertItemTemplate> <asp:DropDownList ID="DropDownList2" runat="server" DataSourceID="AccessDataSource2" DataTextField="privacy_level_name" DataValueField="privacy_level_id"> </asp:DropDownList> <asp:AccessDataSource ID="AccessDataSource2" runat="server" DataFile="~/App_Data/VisageFinal.mdb" SelectCommand="SELECT * FROM [PrivacyLevels]"></asp:AccessDataSource> </InsertItemTemplate> <ItemTemplate> <asp:Label ID="Label1" runat="server" Text='<%# Bind("date_of_birth") %>'></asp:Label> </ItemTemplate> </asp:TemplateField> <asp:TemplateField HeaderText="course_id" SortExpression="course_id"> <EditItemTemplate> <asp:DropDownList ID="DropDownList3" runat="server" DataSourceID="AccessDataSource3" DataTextField="course_name" DataValueField="course_id"> </asp:DropDownList> <asp:AccessDataSource ID="AccessDataSource3" runat="server" DataFile="~/App_Data/VisageFinal.mdb" SelectCommand="SELECT * FROM [Courses]"> </asp:AccessDataSource> </EditItemTemplate> <InsertItemTemplate> <asp:DropDownList ID="DropDownList22" runat="server" DataSourceID="AccessDataSource22" DataTextField="privacy_level_name" DataValueField="privacy_level_id"> </asp:DropDownList> <asp:AccessDataSource ID="AccessDataSource22" runat="server" DataFile="~/App_Data/VisageFinal.mdb" SelectCommand="SELECT * FROM [PrivacyLevels]"></asp:AccessDataSource> </InsertItemTemplate> <ItemTemplate> <asp:DropDownList ID="DropDownList3" runat="server" DataSourceID="AccessDataSource3" DataTextField="course_name" DataValueField="course_id" Enabled="False"> </asp:DropDownList> <asp:AccessDataSource ID="AccessDataSource3" runat="server" DataFile="~/App_Data/VisageFinal.mdb" SelectCommand="SELECT * FROM [Courses]"></asp:AccessDataSource> </ItemTemplate> </asp:TemplateField> <asp:TemplateField HeaderText="nationality_id" SortExpression="nationality_id"> <EditItemTemplate> <asp:DropDownList ID="DropDownList1" runat="server" DataSourceID="AccessDataSource20" DataTextField="nationality_name" DataValueField="nationality_id"> </asp:DropDownList> <asp:AccessDataSource ID="AccessDataSource20" runat="server" DataFile="~/App_Data/VisageFinal.mdb" SelectCommand="SELECT * FROM [Nationalities]"> </asp:AccessDataSource> </EditItemTemplate> <InsertItemTemplate> <asp:DropDownList ID="DropDownList1" runat="server" DataSourceID="AccessDataSource20" DataTextField="nationality_name" DataValueField="nationality_id"> </asp:DropDownList> <asp:AccessDataSource ID="AccessDataSource20" runat="server" DataFile="~/App_Data/VisageFinal.mdb" SelectCommand="SELECT * FROM [Nationalities]"> </asp:AccessDataSource> </InsertItemTemplate> <ItemTemplate> <asp:DropDownList ID="DropDownList1" runat="server" DataSourceID="AccessDataSource20" DataTextField="nationality_name" DataValueField="nationality_id" Enabled="False"> </asp:DropDownList> <asp:AccessDataSource ID="AccessDataSource20" runat="server" DataFile="~/App_Data/VisageFinal.mdb" SelectCommand="SELECT * FROM [Nationalities]"> </asp:AccessDataSource> </ItemTemplate> </asp:TemplateField> <asp:TemplateField HeaderText="residence_id" SortExpression="residence_id"> <EditItemTemplate> <asp:DropDownList ID="DropDownList4" runat="server" DataSourceID="AccessDataSource4" DataTextField="residence_name" DataValueField="residence_id"> </asp:DropDownList> <asp:AccessDataSource ID="AccessDataSource4" runat="server" DataFile="~/App_Data/VisageFinal.mdb" SelectCommand="SELECT * FROM [Residences]"></asp:AccessDataSource> </EditItemTemplate> <InsertItemTemplate> <asp:DropDownList ID="DropDownList4" runat="server" DataSourceID="AccessDataSource4" DataTextField="residence_name" DataValueField="residence_id"> </asp:DropDownList> <asp:AccessDataSource ID="AccessDataSource4" runat="server" DataFile="~/App_Data/VisageFinal.mdb" SelectCommand="SELECT * FROM [Residences]"></asp:AccessDataSource> </InsertItemTemplate> <ItemTemplate> <asp:DropDownList ID="DropDownList4" runat="server" DataSourceID="AccessDataSource4" DataTextField="residence_name" DataValueField="residence_id" Enabled="False"> </asp:DropDownList> <asp:AccessDataSource ID="AccessDataSource4" runat="server" DataFile="~/App_Data/VisageFinal.mdb" SelectCommand="SELECT * FROM [Residences]"></asp:AccessDataSource> </ItemTemplate> </asp:TemplateField> <asp:BoundField DataField="course_year" HeaderText="course_year" SortExpression="course_year" /> <asp:TemplateField HeaderText="gender_id" SortExpression="gender_id"> <EditItemTemplate> <asp:DropDownList ID="DropDownList5" runat="server" DataSourceID="AccessDataSource5" DataTextField="gender_name" DataValueField="gender_id"> </asp:DropDownList> <asp:AccessDataSource ID="AccessDataSource5" runat="server" DataFile="~/App_Data/VisageFinal.mdb" SelectCommand="SELECT * FROM [Genders]"></asp:AccessDataSource> </EditItemTemplate> <InsertItemTemplate> <asp:DropDownList ID="DropDownList5" runat="server" DataSourceID="AccessDataSource5" DataTextField="gender_name" DataValueField="gender_id"> </asp:DropDownList> <asp:AccessDataSource ID="AccessDataSource5" runat="server" DataFile="~/App_Data/VisageFinal.mdb" SelectCommand="SELECT * FROM [Genders]"></asp:AccessDataSource> </InsertItemTemplate> <ItemTemplate> <asp:DropDownList ID="DropDownList5" runat="server" DataSourceID="AccessDataSource5" DataTextField="gender_name" DataValueField="gender_id" Enabled="False"> </asp:DropDownList> <asp:AccessDataSource ID="AccessDataSource5" runat="server" DataFile="~/App_Data/VisageFinal.mdb" SelectCommand="SELECT * FROM [Genders]"></asp:AccessDataSource> </ItemTemplate> </asp:TemplateField> <asp:CommandField ShowInsertButton="True" InsertText="Create my user!" /> </Fields> <HeaderStyle BackColor="#5D7B9D" Font-Bold="True" ForeColor="White" /> <EditRowStyle BackColor="#999999" /> <AlternatingRowStyle BackColor="White" ForeColor="#284775" /> </asp:DetailsView> <asp:Button ID="Button1" runat="server" Text="Button" /> <asp:AccessDataSource ID="AccessDataSource1" runat="server" DataFile="~/App_Data/VisageFinal.mdb" DeleteCommand="DELETE FROM [Users] WHERE [user_id] = ?" InsertCommand="INSERT INTO [Users] ([email], [password], [users_name], [image_path], [mobile], [twitter], [privacy_level_id], [nationality_id], [course_id], [residence_id], [course_year], [gender_id]) VALUES ('?', '?', '?', '?', '?', '?', ?, ?, ?, ?, ?, ?)" SelectCommand="SELECT * FROM [Users]" UpdateCommand="UPDATE [Users] SET [email] = ?, [password] = ?, [users_name] = ?, [date_of_birth] = ?, [image_path] = ?, [mobile] = ?, [twitter] = ?, [privacy_level_id] = ?, [nationality_id] = ?, [course_id] = ?, [residence_id] = ?, [has_set_privacy_level] = ?, [course_year] = ?, [gender_id] = ? WHERE [user_id] = ?"> <DeleteParameters> <asp:Parameter Name="user_id" Type="Int32" /> </DeleteParameters> <UpdateParameters> <asp:Parameter Name="email" Type="String" /> <asp:Parameter Name="password" Type="String" /> <asp:Parameter Name="users_name" Type="String" /> <asp:Parameter Name="image_path" Type="String" /> <asp:Parameter Name="mobile" Type="String" /> <asp:Parameter Name="twitter" Type="String" /> <asp:Parameter Name="privacy_level_id" Type="Int32" /> <asp:Parameter Name="nationality_id" Type="Int32" /> <asp:Parameter Name="course_id" Type="Int32" /> <asp:Parameter Name="residence_id" Type="Int32" /> <asp:Parameter Name="has_set_privacy_level" Type="Boolean" /> <asp:Parameter Name="course_year" Type="Int32" /> <asp:Parameter Name="gender_id" Type="Int32" /> <asp:Parameter Name="user_id" Type="Int32" /> </UpdateParameters> <InsertParameters> <asp:Parameter Name="email" Type="String" /> <asp:Parameter Name="password" Type="String" /> <asp:Parameter Name="users_name" Type="String" /> <asp:Parameter Name="image_path" Type="String" /> <asp:Parameter Name="mobile" Type="String" /> <asp:Parameter Name="twitter" Type="String" /> <asp:Parameter Name="privacy_level_id" Type="Int32" /> <asp:Parameter Name="nationality_id" Type="Int32" /> <asp:Parameter Name="course_id" Type="Int32" /> <asp:Parameter Name="residence_id" Type="Int32" /> <asp:Parameter Name="course_year" Type="Int32" /> <asp:Parameter Name="gender_id" Type="Int32" /> </InsertParameters> </asp:AccessDataSource> Any ideas what I've broken?

  Read the article

• Mac OS X software always order files alphabetically rather than by type.

  - by george

  I have noticed many Mac applications sort the files alphabetically rather than by type. A good example would be Coda by panic.com. The files in the file menu are organized alphabetically. I requested for them to add the feature to organize files by type, and they've said that it's a Finder thing. So I looked at other applications to see if they were organizing by type. I noticed Dreamweaver CS4 had this same problem and now including Dreamweaver CS5. There has to be something in the Mac that does this and that I can modify. I played with Spotlight and it now displays its files by type (thinking that's what I can do) but it didn't take effect in other applications. What library are these applications using to display a file menu for their files? here is an example-- file menu layout of coda by panic.com. (i couldnt post another link because it wouldnt let me). can you see how everything is organised alphabetically rather than by folder? i just want the file menu to show all folders first then all the files. 1) http://www.iaddesign.com/coda.png there must be a way to modify mac to let me to do this.

  Read the article

• Is there a programming toolkit for converting "any file type" to a TIFF image?

  - by Ryan

  Hello, I've written several variations of a program. The purpose of the program is to convert "any file type" to a TIFF image represenation of that file, as if it were being printed using a printer. I'm currently using a third party printer driver that I send files to, and it outputs a TIFF image. This is nice, but it requires me to use Office Interop files, and interact with each individual processing application in order to print the files. I had previously tried a toolkit, called Apose .NET, which did not rely on Office Interop, and did not require any printer driver. It did the conversion all on its own and would create a TIFF image. The problem with Aspose .NET was that it did not support a wide variety of input file types. Most notably, it can't do Visio files. My project calls for the ability to create a TIFF image for virtually "any file type". (excluding exes, music files, and stuff) I know that finding something that handles literally any file type is probably not a very feasible task, so I figure if it can at least handle all the Office file types, Adobe types, and other major standard file types, then I can write a custom extension parsing module that uses those processing applications to do the printing of any file type that can be viewed using those applications. So, does anyone know of a toolkit that can do this? Preferably one that does not rely on Office or a printer driver. It does not have to be free, or open source. Or, if you know of an amazing printer driver that does this, I'm open to that too. Thanks in advance, Ryan

  Read the article

• Is it possible in any Java IDE to collapse the type definitions in the source code?

  - by asmaier

  Lately I often have to read Java code like this: LinkedHashMap<String, Integer> totals = new LinkedHashMap<String, Integer>(listOfRows.get(0)) for (LinkedHashMap<String, Integer> row : (ArrayList<LinkedHashMap<String,Integer>>) table.getValue()) { for(Entry<String, Integer> elem : row.entrySet()) { String colName=elem.getKey(); int Value=elem.getValue(); int oldValue=totals.get(colName); int sum = Value + oldValue; totals.put(colName, sum); } } Due to the long and nested type definitions the simple algorithm becomes quite obscured. So I wished I could remove or collapse the type definitions with my IDE to see the Java code without types like: totals = new (listOfRows.get(0)) for (row : table.getValue()) { for(elem : row.entrySet()) { colName=elem.getKey(); Value=elem.getValue(); oldValue=totals.get(colName); sum = Value + oldValue; totals.put(colName, sum); } } The best way of course would be to collapse the type definitions, but when moving the mouse over a variable show the type as a tooltip. Is there a Java IDE or a plugin for an IDE that can do this?

  Read the article

• Is it valid to use unsafe struct * as an opaque type instead of IntPtr in .NET Platform Invoke?

  - by David Jeske

  .NET Platform Invoke advocates declaring pointer types as IntPtr. For example, the following [DllImport("user32.dll")] static extern IntPtr SendMessage(IntPtr hWnd, UInt32 Msg, Int32 wParam, Int32 lParam); However, I find when interfacing with interesting native interfaces, that have many pointer types, flattening everything into IntPtr makes the code very hard to read and removes the typical typechecking that a compiler can do. I've been using a pattern where I declare an unsafe struct to be an opaque pointer type. I can store this pointer type in a managed object, and the compiler can typecheck it form me. For example: class Foo { unsafe struct FOO {}; // opaque type unsafe FOO *my_foo; class if { [DllImport("mydll")] extern static unsafe FOO* get_foo(); [DllImport("mydll")] extern static unsafe void do_something_foo(FOO *foo); } public unsafe Foo() { this.my_foo = if.get_foo(); } public unsafe do_something_foo() { if.do_something_foo(this.my_foo); } While this example may not seem different than using IntPtr, when there are several pointer types moving between managed and native code, using these opaque pointer types for typechecking is a godsend. I have not run into any trouble using this technique in practice. However, I also have not seen an examples of anyone using this technique, and I wonder why. Is there any reason that the above code is invalid in the eyes of the .NET runtime? My main question is about how the .NET GC system treats "unsafe FOO *my_foo". Is this pointer something the GC system is going to try to trace, or is it simply going to ignore it? My hope is that because the underlying type is a struct, and it's declared unsafe, that the GC would ignore it. However, I don't know for sure. Thoughts?

  Read the article

• PayPal return URL

  - by Sam

  Here's the code for my Paypal button: <form action="https://www.sandbox.paypal.com/cgi-bin/webscr" method="post"> <input type="hidden" name="cmd" value="_xclick"> <input type="hidden" name="business" value="[email protected]"> <input type="hidden" name="lc" value="GB"> <input type="hidden" name="button_subtype" value="products"> <input type="hidden" name="no_note" value="1"> <input type="hidden" name="no_shipping" value="1"> <input type="hidden" name="rm" value="0"> <input type="hidden" name="return" value="http://www.example.com"> <input type="hidden" name="item_name" value="My Item"> <input type="hidden" name="amount" value="25.00"> <input type="hidden" name="currency_code" value="GBP"> <input type="hidden" name="bn" value="PP-BuyNowBF:proceed_btn.gif:NonHosted"> <input type="hidden" name="item_number" value="4BD9569402CDE"> <input type="image" src="http://www.example.com/image.gif" border="0" name="submit" alt="PayPal - The safer, easier way to pay online."> <img alt="" border="0" src="https://www.paypal.com/en_GB/i/scr/pixel.gif" width="1" height="1"> </form> Is it possible to add the item_number to the return URL? For example, after completing the payment within PayPal the user gets sent back to http://www.example.com?item_number=4BD9569402CDE

  Read the article

• XML Schema: How to specify an attribute with a custom 'simpleType' type?

  - by mackenir

  In my XML schema definition, I'm trying to restrict the value of an attribute to be an integer between 0 and 100. With reference to the sample schema below, I want attribute 'attr' on element 'root' to have this restriction. To achieve this I define a simpleType 'Percentage' and set this as the 'type' of 'attr'. However, my XML schema editor (VS 2008) flags the attribute up as having a problem: "Type 'Percentage' is not declared or is not a simple type". <?xml version="1.0" encoding="utf-8"?> <xs:schema elementFormDefault="qualified" id="test" xmlns:xs="http://www.w3.org/2001/XMLSchema" targetNamespace="http://testtttt"> <xs:simpleType name="Percentage"> <xs:restriction base="xs:integer"> <xs:minInclusive value="0"/> <xs:maxInclusive value="100"/> </xs:restriction> </xs:simpleType> <xs:element name="root"> <xs:complexType> <xs:attribute name="attr" type="Percentage" use="optional" /> </xs:complexType> </xs:element>

  Read the article

• What is the preferred way in C++ for converting a builtin type (int) to bool?

  - by Martin

  When programming with Visual C++, I think every developer is used to see the warning warning C4800: 'BOOL' : forcing value to bool 'true' or 'false' from time to time. The reason obviously is that BOOL is defined as int and directly assigning any of the built-in numerical types to bool is considered a bad idea. So my question is now, given any built-in numerical type (int, short, ...) that is to be interpreted as a boolean value, what is the/your preferred way of actually storing that value into a variable of type bool? Note: While mixing BOOL and bool is probably a bad idea, I think the problem will inevitably pop up whether on Windows or somewhere else, so I think this question is neither Visual-C++ nor Windows specific. Given int nBoolean; I prefer this style: bool b = nBoolean?true:false; The following might be alternatives: bool b = !!nBoolean; bool b = (nBoolean != 0); Is there a generally preferred way? Rationale? I should add: Since I only work with Visual-C++ I cannot really say if this is a VC++ specific question or if the same problem pops up with other compilers. So it would be interesting to specifically hear from g++ or users how they handle the int-bool case. Regarding Standard C++: As David Thornley notes in a comment, the C++ Standard does not require this behavior. In fact it seems to explicitly allow this, so one might consider this a VC++ weirdness. To quote the N3029 draft (which is what I have around atm.): 4.12 Boolean conversions [conv.bool] A prvalue of arithmetic, unscoped enumeration, pointer, or pointer to member type can be converted to a prvalue of type bool. A zero value, null pointer value, or null member pointer value is converted to false; any other value is converted to true. (...)

  Read the article

• Strongly Typed DataSet column requires custom type to implement IXmlSerializable?

  - by Phil

  I have a strongly typed Dataset with a single table with three columns. These columns all contain custom types. DataColumn1 is of type Parent DataColumn2 is of type Child1 DataColumn3 is of type Child2 Here is what these classes look like: [Serializable] [XmlInclude(typeof(Child1)), XmlInclude(typeof(Child2))] public abstract class Parent { public int p1; } [Serializable] public class Child1 :Parent { public int c1; } [Serializable] public class Child2 : Parent { public int c1; } now, if I add a row with DataColumn1 being null, and DataColumns 2 and 3 populated and try to serialize it, it works: DataSet1 ds = new DataSet1(); ds.DataTable1.AddDataTable1Row(null, new Child1(), new Child2()); StringBuilder sb = new StringBuilder(); using (StringWriter writer = new StringWriter(sb)) { ds.WriteXml(writer);//Works! } However, if I try to add a value to DataColumn1, it fails: DataSet1 ds = new DataSet1(); ds.DataTable1.AddDataTable1Row(new Child1(), new Child1(), new Child2()); StringBuilder sb = new StringBuilder(); using (StringWriter writer = new StringWriter(sb)) { ds.WriteXml(writer);//Fails! } Here is the Exception: "Type 'WindowsFormsApplication4.Child1, WindowsFormsApplication4, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null' does not implement IXmlSerializable interface therefore can not proceed with serialization." I have also tried using the XmlSerializer to serialize the dataset, but I get the same exception. Does anyone know of a way to get around this where I don't have to implement IXmlSerializable on all the Child classes? Alternatively, is there a way to implement IXmlSerializable keeping all default behavior the same (ie not having any class specific code in the ReadXml and WriteXml methods)

  Read the article

• Unity in C# for Platform Specific Implementations

  - by DxCK

  My program has heavy interaction with the operating system through Win32API functions. now i want to migrate my program to run under Mono under Linux (No wine), and this requires different implementations to the interaction with the operating system. I started designing a code that can have different implementation for difference platform and is extensible for new future platforms. public interface ISomeInterface { void SomePlatformSpecificOperation(); } [PlatformSpecific(PlatformID.Unix)] public class SomeImplementation : ISomeInterface { #region ISomeInterface Members public void SomePlatformSpecificOperation() { Console.WriteLine("From SomeImplementation"); } #endregion } public class PlatformSpecificAttribute : Attribute { private PlatformID _platform; public PlatformSpecificAttribute(PlatformID platform) { _platform = platform; } public PlatformID Platform { get { return _platform; } } } public static class PlatformSpecificUtils { public static IEnumerable<Type> GetImplementationTypes<T>() { foreach (Assembly assembly in AppDomain.CurrentDomain.GetAssemblies()) { foreach (Type type in assembly.GetTypes()) { if (typeof(T).IsAssignableFrom(type) && type != typeof(T) && IsPlatformMatch(type)) { yield return type; } } } } private static bool IsPlatformMatch(Type type) { return GetPlatforms(type).Any(platform => platform == Environment.OSVersion.Platform); } private static IEnumerable<PlatformID> GetPlatforms(Type type) { return type.GetCustomAttributes(typeof(PlatformSpecificAttribute), false) .Select(obj => ((PlatformSpecificAttribute)obj).Platform); } } class Program { static void Main(string[] args) { Type first = PlatformSpecificUtils.GetImplementationTypes<ISomeInterface>().FirstOrDefault(); } } I see two problems with this design: I can't force the implementations of ISomeInterface to have a PlatformSpecificAttribute. Multiple implementations can be marked with the same PlatformID, and i dont know witch to use in the Main. Using the first one is ummm ugly. How to solve those problems? Can you suggest another design?

  Read the article

• LINQ .Cast() extension method fails but (type)object works.

  - by Ben Robinson

  To convert between some LINQ to SQL objects and DTOs we have created explicit cast operators on the DTOs. That way we can do the following: DTOType MyDTO = (LinqToSQLType)MyLinq2SQLObj; This works well. However when you try to cast using the LINQ .Cast() extension method it trows an invalid cast exception saying cannot cast type Linq2SQLType to type DTOType. i.e. the below does not work List<DTO.Name> Names = dbContact.tNames.Cast<DTO.Name>() .ToList(); But the below works fine: DAL.tName MyDalName = new DAL.tName(); DTO.Name MyDTOName = (DTO.Name)MyDalName; and the below also works fine List<DTO.Name> Names = dbContact.tNames.Select(name => (DTO.Name)name) .ToList(); Why does the .Cast() extension method throw an invalid cast exception? I have used the .Cast() extension method in this way many times in the past and when you are casting something like a base type to a derived type it works fine, but falls over when the object has an explicit cast operator.

  Read the article

• function not printing out anything

  - by Abdul Latif

  I have the following function below: public function setupHead($title){ $displayHead .='<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en"> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /> <title>'.$title.'</title>'; $displayHead .='<script type="text/javascript" src="'.PATH.'js/jquery-1.3.2.min.js"></script> <script type="text/javascript" src="'.PATH.'js/thickbox.js"></script> <script type="text/javascript" src="'.PATH.'js/ui.core.js"></script> <!--<script type="text/javascript" src="'.PATH.'js/js.js"></script>--> <link rel="stylesheet" href="'.PATH.'css/thickbox.css" type="text/css" media="screen" /> <link rel="stylesheet" type="text/css" href="'.PATH.'css/styles.css"> <link rel="stylesheet" type="text/css" href="'.PATH.'css/menu_allbrowsers.css"> <link rel="stylesheet" href="'.PATH.'css/news.css" type="text/css" media="screen" /> <link rel="stylesheet" href="'.PATH.'css/text.css" type="text/css" media="screen" /> <script type="text/javascript" src="'.PATH.'js/swfobject.js"></script> <!--[if IE 7]><link rel="stylesheet" type="text/css" href="'.PATH.'css/IE7menu.css" /><![endif]--> <!--[if IE 6]><link rel="stylesheet" type="text/css" href="'.PATH.'css/ie6.css" /><![endif]--> <!--[if IE 7]><link rel="stylesheet" type="text/css" href="'.PATH.'css/ie7.css" /><![endif]--> </head>'; return $displayHead; } but when it call is using: echo classname->setupHead($title); nothing gets displayed. doesn't php allow html in strings? Thanks in advance

  Read the article

• remove the blank rows after i removed xml elements?

  - by fayer

  i removed some elements from a xml file with simpledom. the code: $this->xmlDocument->removeNodes("//entity[name='mac']"); here is the initial file: <entity id="1000070"> <name>apple</name> <type>category</type> <entities> <entity id="7002870"> <name>mac</name> <type>category</type> </entity> <entity id="7024080"> <name>iphone</name> <type>category</type> </entity> <entity id="7024080"> <name>ipad</name> <type>category</type> </entity> </entities> </entity> the file afterwards: <entity id="1000070"> <name>apple</name> <type>category</type> <entities> <entity id="7024080"> <name>iphone</name> <type>category</type> </entity> <entity id="7024080"> <name>ipad</name> <type>category</type> </entity> </entities> </entity> i wonder how i could also remove the blank lines that are left after i ran the removal code? thanks!

  Read the article

• WCF: get generic type object (e.g. MyObject<T>) from remote machine

  - by Aaron

  I have two applications that are communicating through WCF. On the server the following object exists: public class MyObject<T> { ... public Entry<T> GetValue() } Where Entry<T> is another object with T Data as a public property. T could be any number of types (string, double, etc) On the client I have ClientObject<T> that needs to get the value of Data from the server (same type). Since I'm using WCF, I have to define my ServiceContract as an interface, and I can't have ClientObject<T> call Entry<T> GetMyObjectValue (string Name) which calls GetValue on the correct MyObject<T> because my interface isn't aware of the type information. I've tried implementing separate GetValue functions (GetMyObjectValueDouble, GetMyObjectValueString) in the interface and then have ClientObject determine the correct one to call. However, Entry<T> val = (Entry<T>)GetMyObjectValueDouble(...); doesn't work because it's not sure about the type information. How can I go about getting a generic object over WCF with the correct type information? Let me know if there are other details I can provide. Thanks!

  Read the article

• C#: at design time, how can I reliably determine the type of a variable that is declared using var?

  - by Cheeso

  I'm working on a completion (intellisense) facility for C# in emacs. The idea is, if a user types a fragment, then asks for completion via a particular keystroke combination, the completion facility will use .NET reflection to determine the possible completions. Doing this requires that the type of the thing being completed, be known. If it's a string, it has a set of known methods; if it's an Int32, it has a separate set of methods, and so on. Using semantic, a code lexer/parser package available in emacs, I can locate the variable declarations, and their types. Given that, it's straightforward to use reflection to get the methods and properties on the type, and then present the list of options to the user. The problem arrives when the code uses var in the declaration. How can I reliably determine the actual type used, when the variable is declared with the var keyword? Just to be clear, I don't need to determine it at runtime. I want to determine it at "Design time". So far the best idea I have is: extract the declaration statement, eg var foo = "a string value"; concatenate a statement foo.GetType(); dynamically compile the resulting C# fragment it into a new assembly load the assembly into a new AppDomain, run the framgment and get the return type. unload and discard the assembly This sounds awfully heavyweight, for each completion request in the editor. Any better ideas out there?

  Read the article

• How do I set an og:type for the first time without losing likes?

  - by Travis

  When I first created my site, I neglected to add the Open Graph tags that Facebook recommends (http://developers.facebook.com/docs/opengraph/), and the site now has about 1200 Facebook likes through a fb:comments widget. http://graph.facebook.com/http://feedtheanimalssamples.com/ shows this: { "id": "http://feedtheanimalssamples.com/", "shares": 1204 } Recently, I've added added the following OG tags: <meta property="fb:app_id" content="59193243341" /> <meta property="og:title" content="Girl Talk - Feed The Animals Samples (old)" /> <meta property="og:image" content="http://feedtheanimalssamples.com/fta_small.png" /> <meta property="og:url" content="http://feedtheanimalssamples.com" /> But when I add the og:type tag: <meta property="og:type" content="website" /> and Lint the site, I lose all my likes. http://graph.facebook.com/http://feedtheanimalssamples.com/ starts showing this: { "id": "170545342993850", "name": "Girl Talk - Feed The Animals Samples", "picture": "http://profile.ak.fbcdn.net/hprofile-ak-snc4/188039_170545342993850_3277642_s.jpg", "link": "http://www.facebook.com/pages/Girl-Talk-Feed-The-Animals-Samples/170545342993850", "category": "Website", "website": "http://feedtheanimalssamples.com/", "description": "Interactively identifies the samples in the 2008 album 'Feed The Animals' by mashup artist Girl Talk.", "likes": 1 } (Note the "likes": 1.) So: How do I set the og:type without losing my likes? I'm trying to let my likers know that I've created a new and improved site. I'm following the instuctions at http://developers.facebook.com/blog/post/397 under "Publishing to Connected Users via Graph API", but using that API apparently requires specifying an og:type. Thanks!

  Read the article

• Fortran pointer as an argument to interface procedure

  - by icarusthecow

  Im trying to use interfaces to call different subroutines with different types, however, it doesnt seem to work when i use the pointer attribute. for example, take this sample code MODULE ptr_types TYPE, abstract :: parent INTEGER :: q END TYPE TYPE, extends(parent) :: child INTEGER :: m END TYPE INTERFACE ptr_interface MODULE PROCEDURE do_something END INTERFACE CONTAINS SUBROUTINE do_something(atype) CLASS(parent), POINTER :: atype ! code determines that this allocation is correct from input ALLOCATE(child::atype) WRITE (*,*) atype%q END SUBROUTINE END MODULE PROGRAM testpass USE ptr_types CLASS(child), POINTER :: ctype CALL ptr_interface(ctype) END PROGRAM This gives error Error: There is no specific subroutine for the generic 'ptr_interface' at (1) however if i remove the pointer attribute in the subroutine it compiles fine. Now, normally this wouldnt be a problem, but for my use case i need to be able to treat that argument as a pointer, mainly so i can allocate it if necessary. Any suggestions? Mind you I'm new to fortran so I may have missed something edit: forgot to put the allocation in the parents subroutine, the initial input is unallocated EDIT 2 this is my second attempt, with caller side casting MODULE ptr_types TYPE, abstract :: parent INTEGER :: q END TYPE TYPE, extends(parent) :: child INTEGER :: m END TYPE TYPE, extends(parent) :: second INTEGER :: meow END TYPE CONTAINS SUBROUTINE do_something(this, type_num) CLASS(parent), POINTER :: this INTEGER type_num IF (type_num == 0) THEN ALLOCATE (child::this) ELSE IF (type_num == 1) THEN ALLOCATE (second::this) ENDIF END SUBROUTINE END MODULE PROGRAM testpass USE ptr_types CLASS(child), POINTER :: ctype SELECT TYPE(ctype) CLASS is (parent) CALL do_something(ctype, 0) END SELECT WRITE (*,*) ctype%q END PROGRAM however this still fails. in the select statement it complains that parent must extend child. Im sure this is due to restrictions when dealing with the pointer attribute, for type safety, however, im looking for a way to convert a pointer into its parent type for generic allocation. Rather than have to write separate allocation functions for every type and hope they dont collide in an interface or something. hopefully this example will illustrate a little more clearly what im trying to achieve, if you know a better way let me know

  Read the article

• Pass the return type as a parameter in java?

  - by jonderry

  I have some files that contain logs of objects. Each file can store objects of a different type, but a single file is homogeneous -- it only stores objects of a single type. I would like to write a method that returns an array of these objects, and have the array be of a specified type (the type of objects in a file is known and can be passed as a parameter). Roughly, what I want is something like the following: public static <T> T[] parseLog(File log, Class<T> cls) throws Exception { ArrayList<T> objList = new ArrayList<T>(); FileInputStream fis = new FileInputStream(log); ObjectInputStream in = new ObjectInputStream(fis); try { Object obj; while (!((obj = in.readObject()) instanceof EOFObject)) { T tobj = (T) obj; objList.add(tobj); } } finally { in.close(); } return objList.toArray(new T[0]); } The above code doesn't compile (there's an error on the return statement, and a warning on the cast), but it should give you the idea of what I'm trying to do. Any suggestions for the best way to do this?

  Read the article

• How to make restrictions on XML Schema Complex type?

  - by chobo2

  Hi I am reading the tutorials on w3cschools ( http://www.w3schools.com/schema/schema_complex.asp ) but they don't seem to mention how you could add restrictions on complex types. Like for instance I have this schema. <xs:element name="employee"> <xs:complexType> <xs:sequence> <xs:element name="firstname" type="xs:string"/> <xs:element name="lastname" type="xs:string"/> </xs:sequence> </xs:complexType> </xs:element> now I want to make sure the firstname is no more then 10 characters long. How do I do this? I tried to put in the simple type for the firstname but it says I can't do that since I am using a complex type. So how do I put restrictions like that on the file so the people who I give the schema to don't try to make the firstname 100 characters.

  Read the article

• C++ and its type system: How to deal with data with multiple types?

  - by sub

  "Introduction" I'm relatively new to C++. I went through all the basic stuff and managed to build 2-3 simple interpreters for my programming languages. The first thing that gave and still gives me a headache: Implementing the type system of my language in C++ Think of that: Ruby, Python, PHP and Co. have a lot of built-in types which obviously are implemented in C. So what I first tried was to make it possible to give a value in my language three possible types: Int, String and Nil. I came up with this: enum ValueType { Int, String, Nil }; class Value { public: ValueType type; int intVal; string stringVal; }; Yeah, wow, I know. It was extremely slow to pass this class around as the string allocator had to be called all the time. Next time I've tried something similar to this: enum ValueType { Int, String, Nil }; extern string stringTable[255]; class Value { public: ValueType type; int index; }; I would store all strings in stringTable and write their position to index. If the type of Value was Int, I just stored the integer in index, it wouldn't make sense at all using an int index to access another int, or? Anyways, the above gave me a headache too. After some time, accessing the string from the table here, referencing it there and copying it over there grew over my head - I lost control. I had to put the interpreter draft down. Now: Okay, so C and C++ are statically typed. How do the main implementations of the languages mentioned above handle the different types in their programs (fixnums, bignums, nums, strings, arrays, resources,...)? What should I do to get maximum speed with many different available types? How do the solutions compare to my simplified versions above?

  Read the article

• When calling a static method on parent class, can the parent class deduce the type on the child (C#)

  - by Matt

  Suppose we have 2 classes, Child, and the class from which it inherits, Parent. class Parent { public static void MyFunction(){} } class Child : Parent { } Is it possible to determine in the parent class how the method was called? Because we can call it two ways: Parent.MyFunction(); Child.MyFunction(); My current approach was trying to use: MethodInfo.GetCurrentMethod().ReflectedType; // and MethodInfo.GetCurrentMethod().DeclaringType; But both appear to return the Parent type. If you are wondering what, exactly I am trying to accomplish (and why I am violating the basic OOP rule that the parent shouldn't have to know anything about the child), the short of it is this (let me know if you want the long version): I have a Model structure representing some of our data that persists to the database. All of these models inherit from an abstract Parent. This parent implements a couple of events, such as SaveEvent, DeleteEvent, etc. We want to be able to subscribe to events specific to the type. So, even though the event is in the parent, I want to be able to do: Child.SaveEvent += new EventHandler((sender, args) => {}); I have everything in place, where the event is actually backed by a dictionary of event handlers, hashed by type. The last thing I need to get working is correctly detecting the Child type, when doing Child.SaveEvent. I know I can implement the event in each child class (even forcing it through use of abstract), but it would be nice to keep it all in the parent, which is the class actually firing the events (since it implements the common save/delete/change functionality).

  Read the article

• Why is Scala's type inferencer not able to resolve this?

  - by Levi Greenspan

  In the code snippet below - why do I have to give a type annotation for Nil? Welcome to Scala version 2.8.0.RC2 (OpenJDK Server VM, Java 1.6.0_18). Type in expressions to have them evaluated. Type :help for more information. scala> List(Some(1), Some(2), Some(3), None).foldLeft(Nil)((lst, o) => o match { case Some(i) => i::lst; case None => lst }) <console>:6: error: type mismatch; found : List[Int] required: object Nil List(Some(1), Some(2), Some(3), None).foldLeft(Nil)((lst, o) => o match { case Some(i) => i::lst; case None => lst }) ^ scala> List(Some(1), Some(2), Some(3), None).foldLeft(Nil:List[Int])((lst, o) => o match { case Some(i) => i::lst; case None => lst }) res1: List[Int] = List(3, 2, 1)

  Read the article

< Previous Page | 139 140 141 142 143 144 145 146 147 148 149 150  | Next Page >