protected void TxtQty_TextChanged(object sender, EventArgs e)
    {
        try
        {
            TxtQty.Text          = TxtQty.Text == "" ? "0" : TxtQty.Text;
            TxtPurchaseRate.Text = TxtPurchaseRate.Text == "" ? "0" : TxtPurchaseRate.Text;

            LblTotal.Text = (Convert.ToDecimal(TxtQty.Text) * Convert.ToDecimal(Convert.ToDecimal(TxtPurchaseRate.Text) - Convert.ToDecimal(TxtDisRsChild.Text == "" ? "0" : TxtDisRsChild.Text))).ToString("0.00");
            ImgBtnAdd.Focus();
        }
        catch (Exception ex)
        {
        }
    }
    protected void TxtQty_TextChanged(object sender, EventArgs e)
    {
        try
        {
            TxtSaleRate.Text = TxtSaleRate.Text == "" ? "0" : TxtSaleRate.Text;
            TxtQty.Text      = TxtQty.Text == "" ? "0" : TxtQty.Text;

            LblTotal.Text = (Convert.ToDouble(TxtSaleRate.Text) * Convert.ToDouble(TxtQty.Text)).ToString("0.00");
            ImgBtnAdd.Focus();
        }
        catch (Exception ex)
        {
        }
    }