Need assistance figuring out an issue with the implementation of a .Net Delegate

Hi:

I've run into a runtime exception with trying to use a .Net Delegate. I'm using MS VisualStudio 2008.

I'm essentailly trying to wrap access to a datagridview control with a delegate. Upon entering the method in question, I test to see whether an Invoke is required or not. If it is, I wrap the my method call with a delegate. Upon calling the delegated method, I get a runtime exception. I've used this exact method of invoking in other programs, and it has worked fine. For the life of me, I can't seem to figure what the issue is here.

It appears to be throwing the exception on the 2nd parameter. It is of type string and gets cast to an object[].

Things I've tried:
------------------
1) Remove the offending 2nd (string) parameter, and everything works fine.
2) Remove the 1st (int) parameter, and everything works fine.

Here is the exception I get:
----------------------------
System.ArgumentException: Object of type 'System.Object[]' cannot be converted to type 'System.String'.
   at System.Windows.Forms.Control.MarshaledInvoke(Control caller, Delegate method, Object[] args, Boolean synchronous)
   at System.Windows.Forms.Control.Invoke(Delegate method, Object[] args)
   at IntervalData.NStarImporter.MainForm.UpdateImportResultsGrid(Int32 iMeterID, String sMessage) in C:\Documents and Settings\xxxx\My Documents\Visual Studio 2008\Projects\IDS\Development\xxx\trunk\xxx\MainForm.cs:line 567}

Here is a code snippet:
-----------------------
        delegate void UpdateImportResultsGridDelegate(int iParam, string message);
        public void UpdateImportResultsGrid(int iParam, string sMessage)
        {
            try
            {
                // Does this require being wrapped by an invoke?
                if (this.dataGridViewImportResults.InvokeRequired.Equals(true))
                {
                    UpdateImportResultsGridDelegate del = new UpdateImportResultsGridDelegate(UpdateImportResultsGrid);
                    this.dataGridViewImportResults.Invoke(del, iParam, new object[] { sMessage });
                }

                //  Do a bunch of updating to the datagridview control

            catch (Exception ex)
            {
                throw ex;
            }
        }

I've used the exact same construct in other applications, and it has worked fine.
This is what confuses me.

Any and all help will be appreciated.

Thanks,
JohnB

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