pre-populate value into RadGrid Insert

protected void RadGrid1_ItemCommand(object source, GridCommandEventArgs e)
{
if (e.CommandName == RadGrid.InitInsertCommandName)
{
//enter the code here
}
}
protected void RadGrid1_ItemDataBound(object sender, GridItemEventArgs e)
{
if (e.Item is GridEditFormInsertItem && RadGrid1.MasterTableView.IsItemInserted)
{
GridEditFormInsertItem insertItem = (GridEditFormInsertItem)e.Item;
(insertItem["abc"].Controls[0] as TextBox).Text = "hello world";
}
}