将JavaScript/JSON数组传递给MVC'GET'方法

Question

我正在尝试将一个数组/ IEnumerable Guids传递给MVC'GET'方法,如下所示:

[HttpGet]
public ActionResult ZipResults(IEnumerable<Guid> ids)
{
    using(var zip = new Zip())
    {
        foreach(var id in ids)
        {
            var stream = GetDataStream(id);
            zip.AddEntry("filename.txt", stream);
        }
    }

    var outputStream = new MemoryStream();
    zip.Save(outputStream);

    return FileStreamResult(outputStream, "application/octet-stream"){
        FileDownloadName = "Results.zip" };
}

我的javascript看起来像这样:

$('the-button').click(function(){

    // 1. Get the guids from a table and add to javascript array (works fine)
    // 2. Grey-out screen and show processing indicator (works fine)

    // 3. This is how I'm calling the "ZipResults" action:
    $.ajax({
        url: '@Url.Action("ZipResults", "TheController")',
        type: 'GET',
        data: $.toJSON({ ids: _ids }),
        dataType: 'json',
        contentType: 'application/json;charset=utf-8',
        traditional: true,
        success: function(){
            // Undo the grey-out, and remove processing indicator
        },
        error: function(){
        }
    });
});

我的期望是这将弹出浏览器上的下载对话框.实际上,传递给控制器​​的javascript数组是空的(在服务器端,它在客户端正常工作).此外,这适用于'POST',但是,这种方式使用'POST'方法不会强制下载对话框...

打开建议:)

Answer 1

您应该避免使用GET发送JSON请求.试试这样:

var _ids = [ 
    'e2845bd4-9b3c-4342-bdd5-caa992450cb9', 
    '566ddb9d-4337-4ed7-b1b3-51ff227ca96c',
    '25bc7095-a12b-4b30-aabe-1ee0ac199594'
];

$.ajax({
    url: '@Url.Action("ZipResults", "TheController")',
    type: 'GET',
    data: { ids: _ids },
    dataType: 'json',
    traditional: true,
    success: function() {
        // Undo the grey-out, and remove processing indicator
    },
    error: function() {

    }
});

这就是说,我看到你正在调用一些控制器动作,它返回一个要下载的文件流.你根本不应该使用AJAX来做到这一点.这样做的原因是,在你的成功回调中,你将获得ZIP文件的内容,但是你用它做的并不多.你不能将它保存到客户端计算机,你不能提示用户选择一个保存位置,你几乎被破坏了.

因此,如果要下载文件,则不会调用AJAX.你可以使用一个简单的锚点:

@Html.ActionLink("download zip", "ZipResults", "TheController", null, new { id = "download" })

然后:

$(function() {
    $('#download').click(function() {
        var _ids = [ 
            'e2845bd4-9b3c-4342-bdd5-caa992450cb9', 
            '566ddb9d-4337-4ed7-b1b3-51ff227ca96c',
            '25bc7095-a12b-4b30-aabe-1ee0ac199594'
        ];

        var url = this.href;
        for (var i = 0; i < _ids.length; i++) {
            if (url.indexOf('?') > 0) {
                url += '&ids=' + encodeURIComponent(_ids[i]);
            } else {
                url += '?ids=' + encodeURIComponent(_ids[i]);
            }
        }

        window.location.href = url;

        return false;
    });
});