gridview文件下载不起作用

Question

我在我的 gridview 中添加了一个下载链接。当我单击该文件时不会下载，但我可以在 chrome.Click to see response in chrome 中看到响应，我可以在 chrome 开发人员工具响应选项卡中看到文件数据，但下载代码不起作用。请帮忙。

 protected void GridView1_RowCommand1(object sender, GridViewCommandEventArgs e)
{
    try
    {
        if (e.CommandName == "downloadfile")
        {
            int rowId = Convert.ToInt32(e.CommandArgument);
            int fileId = Convert.ToInt32(((Label)GridView1.Rows[rowId].FindControl("lblfileid")).Text);
            string fileName;
            string constr = ConfigurationManager.ConnectionStrings["DMS"].ConnectionString;
            using (SqlConnection con = new SqlConnection(constr))
            {
                SqlCommand cmd = new SqlCommand();

                cmd.CommandText = "select FileName,FileData,FileContentType from Attachment where FileId=@fileId";
                cmd.Parameters.AddWithValue("@fileId", fileId);
                cmd.Connection = con;
                con.Open();
                SqlDataReader sdr = cmd.ExecuteReader();
                if (sdr.Read())
                {

                    fileName = sdr["FileName"].ToString();
                    Response.ContentType = sdr["FileContentType"].ToString();
                    Response.AddHeader("Content-Disposition", "attachment;filename=\"" + sdr["FileName"] + "\"");
                    Response.Charset = "";
                    Response.Cache.SetCacheability(HttpCacheability.NoCache);
                    Response.BinaryWrite((byte[])sdr["FileData"]);
                    Response.Flush(); // Sends all currently buffered output to the client.
                    Response.SuppressContent = true;  // Gets or sets a value indicating whether to send HTTP content to the client.
                    HttpContext.Current.ApplicationInstance.CompleteRequest();

                    //Response.TransmitFile(@"c:\ip.txt");
                }
                con.Close();
            }
        }


    }
    catch (Exception ex)
    {

    }

    Response.End();

}



     <asp:GridView ID="GridView1" runat="server" DataKeyNames="FileId" OnRowDeleting="GridView1_RowDeleting" OnRowDataBound="GridView1_RowDataBound" Width="426px" Height="169px" OnRowCommand="GridView1_RowCommand1" AutoGenerateColumns="false">
    <Columns>
        <asp:HyperLinkField DataTextField="FileName" InsertVisible="False" HeaderText="File Name" />
        <asp:TemplateField>
            <ItemTemplate>
                <asp:LinkButton ID="lnkDownload" Text="Download" CommandArgument='<%# Eval("fileID") %>' runat="server" CommandName="downloadfile" OnClick="lnkDownload_Click" CausesValidation="false"></asp:LinkButton>
            </ItemTemplate>
        </asp:TemplateField>

         <asp:TemplateField>
            <ItemTemplate>
                <asp:LinkButton ID="lnlDwn" Text="Download file" runat="server" OnClick="lnlDwn_Click" CommandArgument='<%# Eval("fileID") %>'></asp:LinkButton>
            </ItemTemplate>
        </asp:TemplateField>

        <asp:TemplateField>
            <ItemTemplate>
                <asp:Label ID="lblfileid" Text='<%# Bind("FileId") %>' runat="server" Visible="false"></asp:Label>
            </ItemTemplate>
        </asp:TemplateField>
        <asp:ButtonField CommandName="downloadfile" HeaderText="action" Text="Download" />
        <asp:ButtonField CommandName="DeleteFile" HeaderText="action" Text="Delete File" />
                </Columns>
</asp:GridView>

Answer 1

您需要发起整页回发，当您使用更新面板下载时，您需要在更新面板内使用回发触发器，如下所示：

   <asp:UpdatePanel runat="server">
        <Triggers>
            <asp:PostBackTrigger ControlID="YourControlID" />
        </Triggers>
    </asp:UpdatePanel>