根据行中的值编辑 GridView 中单元格的可见性

Question

当行中最后一个单元格的值等于用户 ID 的会话值时，我正在尝试将我的删除按钮可见性设置为 true

Girdview 更新：

<Columns>
<asp:TemplateField>
    <ItemTemplate>
        <%# Container.DataItemIndex + 1 %>
    </ItemTemplate>
</asp:TemplateField>
<asp:BoundField DataField="attachID" HeaderText="Attachment ID" SortExpression="atID" HeaderStyle-CssClass="hidcol" ItemStyle-CssClass="hidcol"/>
<asp:BoundField DataField="attachmentTitle" HeaderText="Attachment Title" SortExpression="attachmentTitle" />
<asp:BoundField DataField="attachmentType" HeaderText="Attachment Type" SortExpression="attachmentType" />
<asp:BoundField DataField="attachmentDescription" HeaderText="Attachment Description" SortExpression="attachmentDescription" />
<asp:BoundField DataField="attachmentDate" HeaderText="Attachment Date" SortExpression="attachmentDate" />
<asp:TemplateField>
    <ItemTemplate>
        <asp:LinkButton ID="LinkButton1" runat="server" CommandName="download"  CommandArgument='<%# Eval("attachmentFile") %>'><img src="CSS/images/download.png" alt="Download File" /></asp:LinkButton>
    </ItemTemplate>
</asp:TemplateField>
<asp:TemplateField ShowHeader="False">
    <ItemTemplate>
       <asp:ImageButton ID="ImageButton1" runat="server" CausesValidation="False" CommandArgument='<%# Eval("userID") %>' CommandName="Delete" ImageUrl="~/CSS/images/delete_page.png" Text="Delete" />
    </ItemTemplate>
</asp:TemplateField>
</Columns>

如果userID 与session["username"] 匹配，我正在尝试设置删除按钮属性可见

我不确定这是否正确。

更新后的代码：

String searchValue = "" + Session["username"];

    foreach (GridViewRow row in GridView1.Rows)
    {
        // Only look in data rows
        if (row.RowType == DataControlRowType.DataRow ||
            row.RowType == DataControlRowType.EmptyDataRow)
        {
            // Find the delete button by ID
            ImageButton theDeleteButton = row.FindControl("ImageButton1") as ImageButton;

            // Verify the button was found before we try to use it
            if (theDeleteButton != null)
            {
                if (theDeleteButton.CommandArgument != searchValue)
                {
                    // Make the button invisible
                    theDeleteButton.Visible = false;
                }
            }

        }
    }

我怎样才能做到这一点？

提前致谢！

代码已更新

Answer 1

我建议对带有CommandName 属性的删除按钮使用TemplateField（类似于您对下载链接按钮所做的操作）而不是CommandField，因为它会使您的代码隐藏删除按钮清洁器，像这样：

标记：

<asp:TemplateField>
    <ItemTemplate>
        <asp:Button ID="ButtonDelete" runat="server" CommandName="delete"  
                    CommandArgument='<%# Eval("id") %>' Text="Delete" />
    </ItemTemplate>
</asp:TemplateField>

代码隐藏：

foreach (GridViewRow row in GridView1.Rows)
{
    // Only look in data rows
    if (row.RowType == DataControlRowType.DataRow || 
        row.RowType == DataControlRowType.EmptyDataRow)
    {
        // Find the delete button by ID
        Button theDeleteButton = row.FindControl("ButtonDelete") as Button;

        // Verify the button was found before we try to use it
        if(theDeleteButton != null)
        {
            // Make the button invisible
            theDeleteButton.Visible = false;
        }
    }
}

注意：如果尝试的转换无法成功完成，as 运算符将返回 null；因此检查 null 与 theDeleteButton 变量。