problem about invalidcastexception-Collection of common programming errors

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  townsean
  wpf tooltip invalidcastexception
  I need to makes some changes to a ToolTip programmatically. That sounds simple enough. Well, apparently not really. :/I have a ToolTip on a WindowsFormsHost object and I make the following cast to get to the IsOpen property: ((System.Windows.Controls.ToolTip)host.ToolTip).IsOpen = true;This line fails during runtime with an InvalidCastException. Unable to cast object of type ‘System.String’ to type’System.Windows.Controls.ToolTip’.I don’t understand why this is failing. I must be missing som
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  Nich0ls
  c# vb.net linq nhibernate invalidcastexception
  :I have a problem… I opted to use NHibernate 3.3.3 sources instead of the pre-compiled DLL because I’m getting sick of having NHibernate issues and not be able to debug them (ie black box). I did the same with fluent NHibernate.I tested the source I compiled for fluent NHibernate with the precompiled NHibernate DLL and it worked. So I decided to go further and do the same with NHibernate.This is where it sucks : my app starts, search engine vorks, etc… BUT every time I try to save something,
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  Charlie Salts
  c# plugins interface late-binding invalidcastexception
  I’ve done this before in C# for a plugin system which works fine, which is why I’m puzzled as to why this new, separate plugin system is not working the way I would expect.I have my plugin assembly – let’s call it “plugin.dll” and I have my main assembly – let’s call it App.exe. I have an interface called IMyObject and its implementation, MyObject and both are defined in plugin.dll. I’ve copied the exact code file for IMyObject (which the plugin developer has provided to me) into my main App.ex
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  Jeremy Wiggins
  c# exception compiler compilation invalidcastexception
  Possible Duplicate:Compile-time and runtime casting c# As I understand it, the following code will always compile, and will additionally always fail at run-time by throwing an InvalidCastException. Example:public class Post { } public class Question : Post { } public class Answer : Post {public void Fail(){Post p = new Post();Question q = (Question)p; // This will throw an InvalidCastException} }My questions are…If my assumptions are off, then can someone provide an example demonstrating ho
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  ElGaucho
  c# reflection dll assemblies invalidcastexception
  We’re loading assemblies dynamically on demand by reflection By now, we’ve defined five dll’s and all have been preloaded by Assembly.LoadFile(). In one of these assemblies, we have a defined an interface IDeviceConnection, which inherits from IConnection (which is defined in a contracts project that is used by the application and the assemblies).We have managed to create an instance of ParameterManager, which is defined in the exact same dll as the IDeviceConnection interface. But as soon as we
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  Mike Wills
  c# model invalidcastexception
  I work a ton with our IBM i data and I can’t use EF to work with that data. So instead I do something similar to the following:DataTable dt = new DataTable(); using (iDB2Connection conn = new iDB2Connection(_connString)) {using (iDB2Command cmd = new iDB2Command(sb.ToString(), conn)){conn.Open();using (iDB2DataAdapter da = new iDB2DataAdapter(cmd)) { da.Fill(dt); }conn.Close();} }From there I can model the data by doing:var billHistory = from i in dt.AsEnumerable()select new BillHistory{Customer
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  sleekFish
  c# java weka invalidcastexception
  I am currently working on a project in which I need to use FP-Growth algorithm. I know Weka is a handy tool for it. However, I am using C# for coding (due to some other libraries I need). So, I converted weka.jar to weka.dll using IKVM.NET. Below is a code snippet that i have written:FPGrowth FPMiner = new FPGrowth();FPMiner.buildAssociations(dataset);AssociationRules rules = FPMiner.getAssociationRules();List<AssociationRule> rule = rules.getRules();This gives me an error as:Cannot implic
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  user2588873
  asp.net pdf itextsharp invalidcastexception
  I have several ASPX web forms that have many text boxes, radio button lists, combo boxes, and many other fancy Telerik controls. After a page is filled out and the submit button is clicked the whole page needs to be converted to a PDF. I need examples of how I could possibly do this with iTextSharp. I have been messing around with a Test project to see how it works and got the following exception when I added a RadTextBox and a RadComboBox:Unable to cast object of type ‘iTextSharp.text.html.simp
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  Peter Wimmer
  c# com invalidcastexception
  I would like to implement a COM object in C# and also use it in C# (besides C++ and others).Here is the code of the DLL implementing the COM object :namespace TestComServer {[ComVisible(true),Guid(“565D8202-6C0F-4AAB-B0F6-49719CD13045”),InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]public interface ITestObject {void DoSomething();}[ComVisible(true),GuidAttribute(“21293767-A713-49E2-968E-7DDE0B0DAB94”),ClassInterface(ClassInterfaceType.None)]public class TestObject : ITestObject {public Tes
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  J0NNY ZER0
  c# asp.net-mvc-3 invalidcastexception
  Anyone know how to remedy this error?Specified cast is not valid.Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code. Exception Details: System.InvalidCastException: Specified cast is not valid.Here is the line of code where it breaks – var id = (int)httpContext.Request.RequestContext.RouteData.Values[“id”];
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  timss
  c# c#-4.0 datatable invalidcastexception
  This is a take on some experimental code that @Tim Schmelter pointed me in the correct direction towards earlier this afternoon. The majority of it is almost exactly the same as what worked earler, but it is throwing a invalidCastException on the last line or second last line, depending whichever i try. I cannot see why this is.Boolean test = false; string filePathStudent = System.IO.Path.GetFullPath(“StudentInfo.txt”); DataTable studentDataTable = new DataTable();studentDataTable.Columns.Add(“I
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  Justin Niessner
  c# inheritance foreach reference invalidcastexception
  Just have a quick question… any help would be greatly appreciate!I’m writing a database. I have a class called “Mechanism” which is inherited by two other classes called “motorcycle” and “automobile.” How would i go about printing the contents of motorcycle or automobile – depending on what the user has decided to enter into the database? this is what i have so far, it’s giving me this error: InvalidCastException was unhandled. Unable to cast object of type “ConsoleApplication1.Automobile” to

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