I figured out one solution :
In Code Behind:
Protected Sub Gridview1_RowDeleting(sender As Object, e As GridViewDeleteEventArgs)
lbldeletemsg.Visible = True
lbldeletemsg.Text = "DATA DELETED •"
lbldeletemsg.Focus()
ScriptManager.RegisterStartupScript(Me.Page, Me.[GetType](), "KeyToIdentifyfadeoutScript", "Fadeout();", True)
End Sub
In aspx page:
<script type="text/javascript" src="scripts/jquery-1.4.1.min.js">
function Fadeout() {
$("span[id$='lbldeletemsg']").fadeOut(5000);
}
OR
function Fadeout() {
$("span[id$='lbldeletemsg']").fadeOut("slow");
}
</script>