Question

I’m using zedgraph and the following code works fine in Visual Studio 2008 with the project targeting .NET 2.0 to create a list of different x,y points:

Dim coordList As New List(Of PointPairList)
   For i As Integer = 0 To 10
   coordList.Add(New PointPairList())
Next

I’ve tried the exact same code in Visual Studio 2010 in a project targeting .NET 4 as i need to use memory maps, but i can’t populate the list; it says

(0) = Count = (Count) threw an exception of type System.TypeLoadException.
Error – no children available

How come the list works in VS2008 (.NET2) but not in VS2010 (.NET4)?

Edit: The original code below works fine in VS2010(.NET4), it’s just that i can’t create a list of pointpairlists:- Dim coordList As New List(Of PointPairList)

Original code:

Dim list1 As New PointPairList()
For i As Integer = 0 To 10
  list1.Add(x, y1)
Next

Edit 2: Here’s a picture of error which appears before it hits the loop:

Answer 1

The code is working fine. The PointPairList iterator is throwing an exception because you left the PointPairList empty.

Example … (this will not show an error when you view the values after the outer loop)

Dim coordList As New List(Of PointPairList)
For i As Integer = 0 To 10
    Dim pointlist = New PointPairList()
    For x = 0 To 10
        pointlist.Add(x, i)
    Next
    coordList.Add(pointlist)
Next