Question

我有一个gridview

每当我点击一个btn时，都会在gridview中插入并查看。

我的问题是我无法得到金额的总和

当我为gridview添加值以显示

时

我有一个获取金额总和的代码

void GetTotalAmount()
    {
        int GetRefNo;
        decimal GetUnitPrice;

        //GetCart();
        con.Open();
        SqlCommand cmd = new SqlCommand();
        cmd.Connection = con;

        cmd.CommandText = "SELECT SUM(Amount) AS TotalAmount " +
            "FROM PRDetails WHERE POID=@POID";
        cmd.Parameters.AddWithValue("@UserID", Session["userid"].ToString());
        cmd.Parameters.AddWithValue("@POID", POID.Text);

        double totalAmount = 0; 
        SqlDataReader dr = cmd.ExecuteReader();
        if (dr.HasRows)
        {
            while (dr.Read())
            {
                totalAmount = int.Parse(dr["TotalAmount"].ToString());
            }
            lbSubTotal.Text = (totalAmount * .88).ToString("#,###.00");
            cmd.Parameters.AddWithValue("totalAmount", totalAmount.ToString());
            con.Close();
        }
        else
        {
            lbSubTotal.Text = "0.00";
        }
    //     
        con.Close();


    }

网格代码

protected void AddProduct_Click(object sender, EventArgs e)
    {

        decimal price = GetPrice(ID);
        //GetTotalAmount();
        con.Open();
        SqlCommand cmd = new SqlCommand();
        cmd.Connection = con;
        cmd.CommandText = "INSERT INTO PRDetails VALUES (@ProductID, @ProductName, @Price, @Quantity, @Amount, @POID)";
        cmd.Parameters.AddWithValue("@UserID", Session["userid"].ToString());


        cmd.Parameters.AddWithValue("@ProductID", lbProductID.Text);
        cmd.Parameters.AddWithValue("@ProductName", ddlName.SelectedValue);
        cmd.Parameters.AddWithValue("@Price", decimal.Parse(lbPrice.Text));
        cmd.Parameters.AddWithValue("@Quantity", Quantity.Text);
        cmd.Parameters.AddWithValue("@Amount", int.Parse(Quantity.Text) * price);


        cmd.Parameters.AddWithValue("@POID", POID.Text);

        cmd.ExecuteNonQuery();
        GridView1.DataBind();
        con.Close();

每当我添加产品（btn for grid）时，都会出现ERROR：Input string was not in a correct format.

Line 255: totalAmount = int.Parse(dr["TotalAmount"].ToString());

ASP.NET CODES

 <asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False" 
         Width="1000px" AllowPaging="True" HorizontalAlign="Center" PageIndex="20" 
        ShowFooter="True" DataSourceID="details"  >
     <Columns>

         <asp:BoundField DataField="POID" HeaderText="POID" 
             SortExpression="POID" />

         <asp:BoundField DataField="ProductID" HeaderText="ProductID" 
             SortExpression="ProductID" />

         <asp:BoundField DataField="ProductName" HeaderText="ProductName" 
             SortExpression="ProductName" />

         <asp:BoundField DataField="Price" HeaderText="Price" 
             SortExpression="Price" />

         <asp:BoundField DataField="Quantity" HeaderText="Quantity" 
             SortExpression="Quantity" />

         <asp:BoundField DataField="Amount" HeaderText="Amount" 
             SortExpression="Amount" />

     </Columns>
 </asp:GridView>




    <asp:SqlDataSource ID="details" runat="server" 
        ConnectionString="<%$ ConnectionStrings:MyOwnMeatshopConnectionString %>" 
        SelectCommand="SELECT [POID], [ProductID], [ProductName], [Price], [Quantity], [Amount] FROM [PRDetails] WHERE ([POID] = @POID)">
        <SelectParameters>
            <asp:ControlParameter ControlID="POID" Name="POID" PropertyName="Text" 
                Type="Int32" />
        </SelectParameters>
    </asp:SqlDataSource>




  <div class="container">
    <div class="pull-right col-lg-5">
        <h5 style="font-weight: bold" />SUB TOTAL Php   <asp:Label ID="lbSubTotal" runat="server"></asp:Label>

我尝试将其设为int和decimal但不起作用

我的代码不完整？

请帮助伙计们。先感谢您！仍然是c＃

的新手

Answer 1

您可以更改小数价格= GetPrice（ID）;加倍价格= GetPrice（ID）; 对不起，我没有足够的代表发表评论。

将字符串转换为双ERROR OCCURS

1 个答案: