Error : RegisterForEventValidation can only be called during Render();

To resolve the above error, add the following.

<%@ Page Language="C#" EnableEventValidation = "false"%>

.ColumnName and .ColumnName have conflicting properties: DataType property mismatch while megrge datasets

by using the following code block, we can avoid the error

VB.Net Code

ds1.Tables(0).Merge(ds2.Tables(0), True, MissingSchemaAction.Ignore)

how to Merge two datasets in asp.net

we can merge two datasets using the following code

VB.Net Code

Dim ds1 As New DataSet
Dim ds2 As New DataSet

If ds1 .Tables(0).Rows.Count > 0 Or ds2.Tables(0).Rows.Count > 0 Then
ds1.Tables(0).Merge(ds2.Tables(0), True, MissingSchemaAction.Ignore)
                gvResults.DataSource = ds1
                gvResults.DataBind()
End If