protected void txt_expence_TextChanged(object sender, EventArgs e) { bl.e_name = txt_expence.Text; DataSet ds = new DataSet(); ds = dl.secectexpencname(bl); if (ds.Tables[0].Rows.Count > 0) { ScriptManager.RegisterStartupScript(this, this.GetType(), "redirect", "alert('The Expence Name Already Exists'); window.location='addexpence.aspx';", true); } }