Help Using Try Catch Exception Please

  Protected Sub detailsview1_ItemDeleting(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.DetailsViewDeleteEventArgs)
Dim label2 As Label = CType(detailsview1.FindControl("label2"), Label)
Try

Catch sqlEx As SqlClient.SqlException
If sqlEx.Message.Contains("DELETE statement conflicted with COLUMN REFERENCE") Then
label2.Visible = True
label2.Text = "You cannot delete this Agent Type as it has a call weighting assigned to it, remove the weightings before you try to delete it"
e.Cancel = True
End If
End Try
End Sub Hi, Im using vb.net sql2005 and visual studio 2005

I have 2 tables which have a foregin key relationship.  When i try to delete information from within one of my aspx pages it rightly comes up with an application errror, something along the lines of

 DELETE statement conflicted with COLUMN REFERENCE constraint 'FK_callScore_agentType'. The conflict occurred in database 'Merlin_####', table 'callScores', column 'typeID'.
The statement has been terminated.

I have looked around and can see people talking about using a try catch excpetion however i need to know how id implement this using the detailsview1_itemdeleting event. Ive never used this before and havent found a decent tutorial to help.

So far i have this code but im stuck as im not sure that this is correct but more importantly what i put in the try method. Protected Sub detailsview1_ItemDeleting(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.DetailsViewDeleteEventArgs)
Dim label2 As Label = CType(detailsview1.FindControl("label2"), Label)
Try
(WHAT GOES HERE)
Catch sqlEx As SqlClient.SqlException
If sqlEx.Message.Contains("DELETE statement conflicted with COLUMN REFERENCE") Then
label2.Visible = True
label2.Text = "You cannot delete this Agent Type as it has a call weighting assigned to it, remove the weightings before you try to delete it"
e.Cancel = True
End If
End Try
End Sub Your help would be greatly appreciated