如何通过在文本框中输入索引来选择网格视图行

Question

我正在使用 asp.net c# 开发一个 Web 应用程序。我的项目是从 g 邮件下载邮件并在网格视图中显示。我已经下载了邮件并在网格视图中显示。在我的网站中，所有控件都只使用键盘键选择。我需要从网格视图中选择每一行而不鼠标单击只需在文本框中输入行索引，然后重定向到另一个页面。我在另一个网格视图中尝试了代码并且它的工作 how select grid view row by entering index in a text box 但是当我在我的项目中应用相同的代码时它不起作用

这是我的代码

收件箱.aspx

<asp:Label ID="lblusername" runat="server" Font-Bold="True" Font-Size="X-Large" 
    ForeColor="#A2979E"></asp:Label>
    <br />
    <asp:TextBox runat="server" ID="txtindex"></asp:TextBox>
    <asp:Button runat="server" Text="Read Mail" ID="btnread" 
    onclick="btnread_Click" />
    <asp:Label ID="Label1" runat="server" Text="Label"></asp:Label>
<asp:Label ID="Label2" runat="server" Text="Label"></asp:Label>
    <br />
    <asp:GridView ID="gvinbox" runat="server" AutoGenerateColumns="false" 
    ShowFooter="false" Height="103px" Width="795px" BorderStyle="Solid" 
    Font-Bold="True" Font-Names="Century Gothic" CellPadding="7" 
    style="margin-right: 0px">
    <Columns>
    <asp:BoundField HeaderText="FROM" DataField="From" />
    <asp:HyperLinkField HeaderText="SUBJECT" DataNavigateUrlFields="MessageNumber" DataNavigateUrlFormatString="~/Showmessage.aspx?MessageNumber={0}" Target="_blank" DataTextField="Subject" />
    <asp:BoundField HeaderText="DATE" DataField="DateSent" />


    </Columns>




    </asp:GridView>

收件箱.aspx.cs

protected void Page_Load(object sender, EventArgs e)
    {

        Pop3Client pop3Client;
        if (Session["Pop3Client"] == null)
        {
            pop3Client = new Pop3Client();
            pop3Client.Connect("pop.gmail.com", int.Parse("995"), true);
            pop3Client.Authenticate("abc@gmail.com", "123456");
            Session["Pop3Client"] = pop3Client;
        }
        else
        {
            pop3Client = (Pop3Client)Session["Pop3Client"];
        }
        int count = pop3Client.GetMessageCount();
        DataTable dtMessages = new DataTable();
        dtMessages.Columns.Add("MessageNumber");
        dtMessages.Columns.Add("From");
        dtMessages.Columns.Add("Subject");
        dtMessages.Columns.Add("DateSent");
        dtMessages.Columns.Add("Attachment");
        int counter = 0;
        for (int i = count; i >= 1; i--)
        {
            Message message = pop3Client.GetMessage(i);
            dtMessages.Rows.Add();
            dtMessages.Rows[dtMessages.Rows.Count - 1]["MessageNumber"] = i;
            dtMessages.Rows[dtMessages.Rows.Count - 1]["From"] = message.Headers.From.Address;
            dtMessages.Rows[dtMessages.Rows.Count - 1]["Subject"] = message.Headers.Subject;
            dtMessages.Rows[dtMessages.Rows.Count - 1]["DateSent"] = message.Headers.DateSent.ToLocalTime();


            counter++;
            if (counter > 10)
            {
                break;
            }


        }


        gvinbox.DataSource = dtMessages;
        gvinbox.DataBind();
    }



    protected void btnread_Click(object sender, EventArgs e)
    {
        int index, aid;

        if (int.TryParse(txtindex.Text, out index) &&
            int.TryParse((gvinbox.DataKeys[index].Value.ToString()), out aid))
        {

            Response.Redirect(string.Format("Showmessage.aspx?MessageNumber={0}", aid));
        }
    }

Answer 1

在inbox.aspx.cs Page_Load中，将DtatTable保存在Session中：

    ... ... ...
    Session["Messages"] = dtMessages;
    gvinbox.DataSource = dtMessages;
    gvinbox.DataBind();
}

在 Showmessage.aspx.cs Page_Load 中获取表格行：

protected void Page_Load(object sender, EventArgs e)
{
    if (!IsPostBack)
    {
        int messageNumber = 0;

        DataTable dtMessages = (DataTable)Session["Messages"];
        if (int.TryParse(Request.QueryString["MessageNumber"].ToString(), out messageNumber) && dtMessages != null)
        {
            var m = (from DataRow dr in dtMessages.Rows
                        where (string)dr["MessageNumber"] == messageNumber.ToString()
                        select dr).FirstOrDefault();
            if (m != null)
            {
                string sOut = m["From"].ToString() + "<br />" +
                                m["Subject"].ToString() + "<br />" +
                                m["DateSent"].ToString();
                Response.Write(sOut);
            }

        }
    }
}   

希望它有意义！

编辑：为避免索引超出范围错误，我们需要修复 btnread_Click 方法，如下所示：

protected void btnread_Click(object sender, EventArgs e)
{
    int index, aid;


    if (int.TryParse(txtindex.Text, out index))
    {
        // Index is 0 based, but we input row number from 1
        // So we have to sutract 1 from input
        index--;

        if ((index >= 0) && (index <= gvinbox.DataKeys.Count) && (int.TryParse((gvinbox.DataKeys[index].Value.ToString()), out aid))
        {
            Response.Redirect(string.Format("Showmessage.aspx?MessageNumber={0}", aid));
        }
        else
        {
            // Input out of range
            // Do whatever to display error
        }
    }
}

Answer 2

你需要给DataKeyNames="MessageNumber"如下

<asp:GridView ID="gvinbox" runat="server" AutoGenerateColumns="false" 
    ShowFooter="false" Height="103px" Width="795px" BorderStyle="Solid" 
    Font-Bold="True" Font-Names="Century Gothic" CellPadding="7" 
    style="margin-right: 0px" DataKeyNames="MessageNumber">