gridview中的文本框未检索数据

Question

我在网格视图上遇到了一些问题。 我有一个列为5的网格视图。当我从顶部选择添加项目时，底部的网格视图将被刷新。 同时，它正在从数据库中检索一些数据并将其显示在网格视图的文本框中。 这是我的按钮动作事件方法：

protected void lbnAdd_Click(object sender, EventArgs e)
    {
        List<ProductPacking> prodVariantDetail = new List<ProductPacking>();

        // get the last product variant IDs from ViewState
        prodVariantIDList = this.SelectedVariantDetailIDs;

        foreach (RepeaterItem ri in Repeater1.Items)
        {
            GridView gvProduct = (GridView)ri.FindControl("gvProduct");
            foreach (GridViewRow gr in gvProduct.Rows)
            {
                CheckBox cb = (CheckBox)gr.FindControl("cbCheckRow");
                if (cb.Checked)
                {
                    // add the corresponding DataKey to idList
                    prodVariantIDList.Add(gvProduct.DataKeys[gr.RowIndex].Value.ToString());
                }
            }
        }
        for (int i = 0; i < prodVariantIDList.Count; i++)
        {
            prodVariantDetail.Add(prodPackBLL.getProdVariantDetailByID(prodVariantIDList[i]));

            foreach (GridViewRow gr in gvFinalised.Rows)
            {
                //Get the product packaging quantity by productName
                string name = gr.Cells[2].Text;
                int productQuantity = packBLL.getProductQuantityByName(name);
                TextBox tb = (TextBox)gr.Cells[5].FindControl("tbQuantity");
                tb.Text = productQuantity.ToString();
            }
        }

        gvFinalised.DataSource = prodVariantDetail;
        gvFinalised.DataBind();

        // save prodVariantIDList to ViewState
        this.SelectedVariantDetailIDs = prodVariantIDList;
    }

但是，它只是一直向我返回0。我确实检查了SQL语句，都向我返回了正确的值。 有没有什么办法解决这一问题？

提前致谢。

编辑

<asp:GridView ID="gvFinalised" runat="server" AutoGenerateColumns="False" CellPadding="2" ForeColor="#333333" GridLines="None" Width="740px" DataKeyNames="id">
                            <Columns>
                                <asp:BoundField DataField="id" HeaderText="ID" ItemStyle-Width="50px" />
                                <asp:BoundField DataField="categoryName" HeaderText="Category" ItemStyle-Width="100px" />
                                <asp:BoundField DataField="name" HeaderText="Product" ItemStyle-Width="350px" />
                                <asp:BoundField DataField="inventoryQuantity" HeaderText="Stock" ItemStyle-Width="100px" />
                                <asp:BoundField DataField="unitQuantity" HeaderText="Unit" ItemStyle-Width="100px" />
                                <asp:TemplateField HeaderText="Quantity" ItemStyle-HorizontalAlign="Center" ItemStyle-Width="200px">
                                    <ItemTemplate>
                                        <asp:TextBox ID="tbQuantity" runat="server" Width="40" Text="0" OnTextChanged="tbQuantity_TextChanged" AutoPostBack="true" />
                                        <asp:Label ID="lblCheckAmount" runat="server" ForeColor="#a94442"></asp:Label>
                                    </ItemTemplate>
                                </asp:TemplateField>
                            </Columns>
                        </asp:GridView>

Answer 1

问题是您在绑定数据之前循环遍历gvFinalised行，因此，当您调用gvFinalised.DataBind()时，在循环内所做的任何操作都将被覆盖。

快速解决方案

移动这个：

foreach (GridViewRow gr in gvFinalised.Rows)
{
    //Get the product packaging quantity by productName
    string name = gr.Cells[2].Text;
    int productQuantity = packBLL.getProductQuantityByName(name);
    TextBox tb = (TextBox)gr.Cells[5].FindControl("tbQuantity");
    tb.Text = productQuantity.ToString();
}

在这之后：

gvFinalised.DataSource = prodVariantDetail;
gvFinalised.DataBind();

替代解决方案

如下面的@SutharMonil所提到的，还有一种使用RowDataBound事件来执行此操作的替代方法。 首先在aspx代码中将OnRowDataBound属性设置为事件处理程序名称，假设名称为gvFinalised_RowDataBound ：

<asp:GridView ID="gvFinalised" runat="server" AutoGenerateColumns="False" CellPadding="2"
        ForeColor="#333333" GridLines="None" Width="740px" DataKeyNames="id" OnRowDataBound="gvFinalised_RowDataBound">

然后在后面的代码中，删除以下代码：

foreach (GridViewRow gr in gvFinalised.Rows)
{
    //Get the product packaging quantity by productName
    string name = gr.Cells[2].Text;
    int productQuantity = packBLL.getProductQuantityByName(name);
    TextBox tb = (TextBox)gr.Cells[5].FindControl("tbQuantity");
    tb.Text = productQuantity.ToString();
}

并添加以下代码：

protected void gvFinalised_RowDataBound(Object sender, GridViewRowEventArgs e)
{
    if (e.Row.RowType == DataControlRowType.DataRow)
    {
        // Display the company name in italics.
        e.Row.Cells[1].Text = "<i>" + e.Row.Cells[1].Text + "</i>";

        //Get the product packaging quantity by productName
        string name = e.Row.Cells[2].Text;
        int productQuantity = packBLL.getProductQuantityByName(name);
        TextBox tb = (TextBox)e.Row.Cells[5].FindControl("tbQuantity");
        tb.Text = productQuantity.ToString();
    }
}

这样，里面的数量文本框gvFinalised时将始终更新gvFinalised.DataBind()被调用。