c# - 无法从列表中获取值以便设置网格 header 值 c#

Question

我正在尝试从出现错误的列表中设置网格 header 值

Object Reference not set to an instance of an object

我先检查了它，但我正在将列表值转换为字符串，在调试时我可以在列表中找到值

代码如下，

        List<string> rows = new List<string>(
new string[] { "Item", "Quantity", "Price" });

                GdItemList.HeaderRow.Cells[0].Text = Convert.ToString(rows[0]);
                GdItemList.HeaderRow.Cells[1].Text = rows[1].ToString();
                GdItemList.HeaderRow.Cells[2].Text = rows[2].ToString();

GdItemList GridView 就像，

<asp:GridView ID="GdItemList" runat="server" ShowHeaderWhenEmpty="True" CellPadding="4"
                    EmptyDataText="No Record Found" ForeColor="#333333" GridLines="None">
                    <AlternatingRowStyle BackColor="White" />
                    <EditRowStyle BackColor="#2461BF" />
                    <FooterStyle BackColor="#507CD1" Font-Bold="True" ForeColor="White" />
                    <HeaderStyle BackColor="#507CD1" Font-Bold="True" ForeColor="White" />
                    <PagerStyle BackColor="#2461BF" ForeColor="White" HorizontalAlign="Center" />
                    <RowStyle BackColor="#EFF3FB" />
                    <SelectedRowStyle BackColor="#D1DDF1" Font-Bold="True" ForeColor="#333333" />
                    <SortedAscendingCellStyle BackColor="#F5F7FB" />
                    <SortedAscendingHeaderStyle BackColor="#6D95E1" />
                    <SortedDescendingCellStyle BackColor="#E9EBEF" />
                    <SortedDescendingHeaderStyle BackColor="#4870BE" />
                </asp:GridView>

Answer 1

List<string> rows = new List<string>(
    new string[] { "Item", "Quantity", "Price" });

GdItemList.Columns[0].HeaderText = Convert.ToString(rows[0]);
GdItemList.Columns[1].HeaderText = rows[1].ToString();
GdItemList.Columns[2].HeaderText = rows[2].ToString();