Question

I have a microsoft visual basic collection (in the namespace Microsoft.VisualBasic) – which uses the Microsoft.VisualBasic.Dll library.

private Collection myCollection;

When i add values to it, I get the following error:

Add failed, duplicate key cannot be inserted

How do i handle that? I need to pass all the ID’s. For example, if have a collection of ID’s (e.g. 10, 11, 12, 13, 10), if the code 10 repeats, this line fails:

myCollection.Add(myIDs.ID);  // this code throws exception

Answer 1

http://msdn.microsoft.com/en-us/library/microsoft.visualbasic.collection.aspx

Before you add, check to see if the collection already contains the key.

if(!myCollection.Contains(myIDs.ID))
    myCollection.Add(myIDs.ID);