invalidoperationexception

I am trying to read financial data and store it. The place I get the financial data from stores the data with incredible precision, however I am only interested in 5 figures after the decimal point. Therefore, I have decided to use t = .quantize(cdecimal.Decimal('.00001'), rounding=cdecimal.ROUND_UP) on the Decimal I create, but I keep getting an InvalidOperation exception. Why is this? >>> import cdecimal >>> c = cdecimal.getcontext() >>> c.prec = 5 >>> s = '45.2091000080109' >>> # s = '0.257585003972054' works! >>> t = cdecimal.Decimal(s).quantize(cdecimal.Decimal('.00001'), rounding

class Program { static void Main(string[] args) { var dictionary = new Dictionary<string, int>() { {"1", 1}, {"2", 2}, {"3", 3} }; foreach (var s in dictionary.Keys) { // Throws the "Collection was modified exception..." on the next iteration // What's up with that? dictionary[s] = 1; } } } I completely understand why this exception is thrown when enumerating a list- it seems reasonable to expect that during enumeration, the Structure of the enumerated object does not change. However- does changing a Value of a dictionary changes its Structure ? Specifically, the structure of its keys? I see

I think that my code should make the ViewBag.test property equal to "No Match" , but instead it throws an InvalidOperationException . Why is this? string str = "Hello1,Hello,Hello2"; string another = "Hello5"; string retVal = str.Split(",".ToCharArray(), StringSplitOptions.RemoveEmptyEntries) .First(p => p.Equals(another)); if (str == another) { ViewBag.test = "Match"; } else { ViewBag.test = "No Match"; //this does not happen when it should } As you can see here , the First method throws an InvalidOperationException when the sequence on which it is called is empty. Since no element of the

I have a standard, non-async action like: [HttpPost] public JsonResult StartGeneratePdf(int id) { PdfGenerator.Current.GenerateAsync(id); return Json(null); } The idea being that I know this PDF generation could take a long time, so I just start the task and return, not caring about the result of the async operation. In a default ASP.Net MVC 4 app this gives me this nice exception: System.InvalidOperationException: An asynchronous operation cannot be started at this time. Asynchronous operations may only be started within an asynchronous handler or module or during certain events in the Page

I am implementing a custom collection implementation that can either be readonly or non-readonly; that is, all the methods that change the collection call a function that is the moral equivalent of: private void ThrowIfReadOnly() { if (this.isReadOnly) throw new SomeException("Cannot modify a readonly collection."); } I am not sure which of NotSupportedException or InvalidOperationException I should use in that case. The MSDN only has one bit of guidance on this precise topic, on NotSupportedException : For scenarios where it is sometimes possible for the object to perform the requested

I have the following code which creates a temporary folder and uses a FileSystemWatcher to poll for files added to the folder on the Location property, and add them to a list: Scratchdisk.cs on Pastebin . The idea is to create a Scratchdisk object, and have FFmpeg extract video frames into it, the FileSystemWatcher builds a list of these files as FFmpeg creates them, and the list is presented as a DependencyObject that my UI binds to. I'm binding to the Scratchdisk object like so: <ItemsControl ItemsSource="{Binding Source=ThumbnailScratchdisk, Path=FileList}"> ... </ItemsControl> On actually

I have a created a WPF application with Entity framework 4.0. When i am trying to insert record in PhoneNumber Table it inserts first record successfully. But, when i loop through some List and try to insert another item into PhoneNumber table it Insert the record but shows error as: InvalidOperationException was handled by user code: The changes to the database were committed successfully, but an error occurred while updating the object context. The ObjectContext might be in an inconsistent state. Inner exception message: A referential integrity constraint violation occurred: The property