javascript - 使用 filedownload jquery 插件处理 FilePathResult 返回值

Question

我正在使用 fileDownload jQuery 插件下载使用 ASP.NET MVC 提供的文件。该操作用 HttpGet 修饰并返回 FilePathResult。当找到文件时它会起作用。如果找不到文件，我不确定在操作中返回什么？

JavaScript:

function showMessageCancelDialog(message, request, titleValue) {

    'use strict';

    $('#messageDialog').html(message);
    $('#messageDialog').dialog({
        resizable: false,
        width: '320px',
        modal: true,
        title: titleValue,
        dialogClass: 'no-close',
        buttons: {
            Cancel: function () {
                request.abort();
                $(this).dialog("close");
            }
        }
    });

}

function hideMessageDialog() {

    'use strict';

    $('#messageDialog').dialog("close");

}

function DownloadAttachment(itemId) {

    'use strict';

    var getAttachmentFileUrl = "/App/Download/GetAttachmentFile?ItemId=" + itemId;

    var ajaxRequest = $.fileDownload(getAttachmentFileUrl, {
                            successCallback: function (message) {
                                hideMessageDialog();
                            },
                            failCallback: function (errorMessage) {
                                hideMessageDialog();
                                showMessageDialog("Download request failed:" + errorMessage, "Download attachment");
                            }
                        });

    showMessageCancelDialog("Download in progress... , ajaxRequest, "Download attachment");
}

ASP.NET:

    if(errorMessage == string.Empty)
    {
                    this.Response.AddHeader("Content-Disposition", "attachment; filename=" + downloadFile);
                    return new FilePathResult(downloadFile, "application/octet-stream");
     }
    else
    {
// WHAT DO I RETURN HERE?
    }  

Answer 1

你可以用你的errorMessage抛出一个错误，jquery函数failCallback()应该捕获这个错误。

else {
  throw new HttpException(404, errorMessage);
}