my gridview update code is below

protected void GridView1_RowUpdating(object sender, GridViewUpdateEventArgs e) { SqlConnection con = new SqlConnection(Class1.con); int userid1 = Convert.ToInt32(GridView1.DataKeys[e.RowIndex].Value.ToString()); // Label lblstid = (Label)GridView1.Rows[e.RowIndex].FindControl("lblstId"); TextBox txtiname = (TextBox)GridView1.Rows[e.RowIndex].FindControl("txtiname"); TextBox txticode = (TextBox)GridView1.Rows[e.RowIndex].FindControl("txtcode"); TextBox txtname = (TextBox)GridView1.Rows[e.RowIndex].FindControl("txtname"); TextBox txtaddr= (TextBox)GridView1.Rows[e.RowIndex].FindControl("txtaddr"); TextBox txtgender = (TextBox)GridView1.Rows[e.RowIndex].FindControl("txtgender"); TextBox txtoccup = (TextBox)GridView1.Rows[e.RowIndex].FindControl("txtoccup"); TextBox txtmob = (TextBox)GridView1.Rows[e.RowIndex].FindControl("txtmob"); TextBox txtemail = (TextBox)GridView1.Rows[e.RowIndex].FindControl("txtemail"); TextBox txtuser = (TextBox)GridView1.Rows[e.RowIndex].FindControl("txtuser"); TextBox txtpass= (TextBox)GridView1.Rows[e.RowIndex].FindControl("txtpass"); TextBox txthint = (TextBox)GridView1.Rows[e.RowIndex].FindControl("txthint"); con.Open(); SqlCommand cmd = new SqlCommand("Update Uregistration set iname='" + txtiname.Text + "',icode='" + txticode.Text + "',name='" + txtname.Text + "',address='" + txtaddr.Text + "',gender='" + txtgender.Text + "',occupation='" + txtoccup.Text.Trim() + "',mob='" + txtmob.Text + "',email='" + txtemail.Text + "',username='" + txtuser.Text + "',password='" + txtpass.Text + "',hint='" + txthint.Text + "' where userid= '" + userid1 + "'", con); cmd.ExecuteNonQuery(); con.Close(); ScriptManager.RegisterStartupScript(this, this.GetType(), "Message", "alert('Data Updated Successfully');", true); GridView1.EditIndex = -1; BindGrid(); }