javascript - 显示有关导出完整 RadGrid Telerik Web 组件的数据的 javascript 警报

Question

我正在使用名为 RadGrid 的 Telerik Web 组件，该组件与 Asp.Net ObjectDataSource 绑定(bind)。它允许将绑定(bind)数据导出为 Excel/PDF/Word 格式。问题是文件下载完成后我无法触发 JavaScript 警报。我已经在 J​​avascript 上尝试过 OnResponseEnd 方法，但它不起作用。

有什么建议吗？

这是迄今为止我的代码隐藏代码。

protected void bXls_Click(object sender, EventArgs e)
    {
        RadGrid1.MasterTableView.GetColumn("Historico").Visible = false;
        RadGrid1.MasterTableView.GetColumn("TareaIdExport").Visible = true;

        RadGrid1.ExportSettings.IgnorePaging = true;
        RadGrid1.ExportSettings.OpenInNewWindow = false;
        RadGrid1.MasterTableView.ExportToExcel();
    }

以及组件代码的简短版本

<telerik:RadGrid ID="RadGrid1" runat="server"
                    AutoGenerateColumns="False"
                    Culture="es-ES"
                    GroupPanelPosition="Top" DataSourceID="objGrid"
                    OnItemCommand="RadGrid1_ItemCommand"
                    OnItemDataBound="RadGrid1_ItemDataBound"
                    RenderMode="Lightweight"
                    OnPreRender="RadGrid1_PreRender1"
                    AllowFilteringByColumn="True"
                    AllowPaging="True"
                    AllowSorting="True"
                    OnItemCreated="RadGrid1_ItemCreated"
                    PageSize="4"
                    OnGridExporting="RadGrid1_GridExporting"
                    OnPdfExporting="RadGrid1_PdfExporting"> 
</telerik:RadGrid>

Answer 1

由于导出需要完整的回发，因此不能使用 ajax 来限制从帖子返回的内容。这使得处理整个事件变得困难。您可以做的是使用将从导出的完整回发中返回的 cookie。以下教程使用此方法来解决导出期间显示 AjaxLoadingPanel 的类似问题。

解决方案总结如下。导出完成后，服务器端的 cookie 将添加到表单中。同时，客户端正在轮询并寻找此 cookie。当客户端找到cookie时，表示导出完成。

Show loading panel when exporting RadGrid

以下是根据您的场景调整的代码工作示例:

ASPX:

function gridCommand(sender, args) {
  if (args.get_commandName().startsWith("Export")) {

    //initiate cookie polling
    appendDownloadToken();
  }
}

function appendDownloadToken() {
  window._downloadToken = new Date().getTime() + "";
  //add a form field containing the download token before submit
  $telerik.$("<input type='hidden' id='_downloadToken' name='_downloadToken' value='" + window._downloadToken + "' />").appendTo(document.forms[0]);

  pollDownloadCookie();
}


function pollDownloadCookie() {
  //compare cookie value and initial value
  if (cookie.get("_downloadToken") === window._downloadToken) {
    //erase download token cookie
    cookie.erase("_downloadToken");
    //remove the token value
    delete window._downloadToken;
    //remove the form field
    $telerik.$("#_downloadToken").remove();
    //show alert
    alert('Grid Exported');
  } else {
    setTimeout(pollDownloadCookie, 100);
  }
}

//Helper method to deal with cookies
cookie = {
  get: function(name) {
    var part = document.cookie.split(name + "=")[1];
    return part ? decodeURIComponent(part.split(";")[0]) : null;
  },
  set: function(name, value, days, path, secure) {
    document.cookie = [
      name + "=" + encodeURIComponent(value),
      days ? "expires=" + new Date(new Date().getTime() + (days * 24 * 60 * 60 * 1000)).toUTCString() : "",
      secure ? "secure" : "",
      path ? "path=" + path : "path=/"
    ].join("; ");
  },
  erase: function(name) {
    cookie.set(name, "", -1);
  },
  all: function() {
    var ret = {};
    var arr = document.cookie.split(";");
    for (var i = 0; i < arr.length; i++) {
      if (arr[i]) {
        var pair = arr[i].split("=");
        ret[pair[0]] = decodeURIComponent(pair[1]);
      }
    }
    return ret;
  }
}

<telerik:RadGrid ID="RadGrid1" runat="server" OnNeedDataSource="RadGrid1_NeedDataSource" AutoGenerateColumns="false" OnItemCommand="RadGrid1_ItemCommand">
  <ExportSettings ExportOnlyData="True" HideStructureColumns="True" OpenInNewWindow="True"></ExportSettings>
  <ClientSettings>
    <ClientEvents OnCommand="gridCommand" />
  </ClientSettings>
  <MasterTableView DataKeyNames="ID" CommandItemDisplay="Top">
    <CommandItemSettings ShowExportToExcelButton="true" ShowExportToCsvButton="true" ShowExportToPdfButton="true" ShowExportToWordButton="true" />
    <Columns>
      <telerik:GridBoundColumn UniqueName="Id" DataField="ID" HeaderText="ID"></telerik:GridBoundColumn>
      <telerik:GridBoundColumn UniqueName="Name" DataField="Name" HeaderText="Name"></telerik:GridBoundColumn>
    </Columns>
  </MasterTableView>
</telerik:RadGrid>

C#:

 protected void RadGrid1_NeedDataSource(object sender, 
 GridNeedDataSourceEventArgs e)
 {
     DataTable table = new DataTable();
    table.Columns.Add("ID", typeof(int));
    table.Columns.Add("Name");
    for (int i = 1; i <= 5; i++) {
        table.Rows.Add(i, "Name" + i.ToString());
    }

   RadGrid1.DataSource = table;

  }

protected void RadGrid1_ItemCommand(object sender, GridCommandEventArgs e)
{
    if (e.CommandName.StartsWith("Export")) {
        if (!String.IsNullOrEmpty(Request("_downloadToken"))) {
            Response.Cookies.Add(new HttpCookie("_downloadToken", 
            Request("_downloadToken")));         
        }
    }
}