jquery fileupload插件上传文件的问题

[ttddlplp]

在做一个文件上传系统，使用了jquery fileupload插件 环境是asp.net

upload.aspx这边

<form id="fileupload" method="POST" enctype="multipart/form-data">
<div class="row-fluid fileupload-buttonbar">
<div class="span7">
<span class="btn green fileinput-button">
<i class="icon-plus icon-white"></i>
<span>Add files...</span>
<input type="file" name="files[]" multiple>
</span>
<button type="submit" class="btn blue start">
<i class="icon-upload icon-white"></i>
<span>Start upload</span>
</button>
</div>
<div class="span5 fileupload-progress fade">
<div class="progress progress-success progress-striped active" role="progressbar" aria-valuemin="0" aria-valuemax="100">
<div class="bar" style="width:0%;"></div>
</div>
<div class="progress-extended"> </div>
</div>
</div>
<div class="fileupload-loading"></div>
<br>
<table role="presentation" class="table table-striped">
<tbody class="files" data-toggle="modal-gallery" data-target="#modal-gallery"></tbody>
</table>
</form>

<div class="span12">
                        <script id="template-upload" type="text/x-tmpl">
                            {% for (var i=0, file; file=o.files[i]; i++) { %}
                            <tr class="template-upload fade">
                            <td class="preview"><span class="fade"></span></td>
                            <td class="name"><span>{%=file.name%}</span></td>
                            <td class="size"><span>{%=o.formatFileSize(file.size)%}</span></td>
                            {% if (file.error) { %}
                            <td class="error" colspan="2"><span class="label label-important">Error</span> {%=file.error%}</td>
                            {% } else if (o.files.valid && !i) { %}
                            <td>
                            <div class="progress progress-success progress-striped active" role="progressbar" aria-valuemin="0" aria-valuemax="100" aria-valuenow="0"><div class="bar" style="width:0%;"></div></div>
                            </td>
                            <td class="start">{% if (!o.options.autoUpload) { %}
                            <button class="btn">
                            <i class="icon-upload icon-white"></i>
                            <span>上传</span>
                            </button>
                            {% } %}</td>
                            {% } else { %}
                            <td colspan="2"></td>
                            {% } %}
                            <td class="cancel">{% if (!i) { %}
                            <button class="btn red">
                            <i class="icon-ban-circle icon-white"></i>
                            <span>取消</span>
                            </button>
                            {% } %}</td>
                            </tr>
                            {% } %}     
                        </script>
                        <script id="template-download" type="text/x-tmpl">
                            {% for (var i=0, file; file=o.files[i]; i++) { %}
                            <tr class="template-download fade">
                            {% if (file.error) { %}
                            <td></td>
                            <td class="name"><span>{%=file.name%}</span></td>
                            <td class="size"><span>{%=o.formatFileSize(file.size)%}</span></td>
                            <td class="error" colspan="2"><span class="label label-important">Error</span> {%=file.error%}</td>
                            {% } else { %}<td class="preview">
                            {% if (file.thumbnail_url) { %}
                            <a class="fancybox-button" data-rel="fancybox-button" href="{%=file.url%}" title="{%=file.name%}">
                            <img src="media/image/{%=file.thumbnail_url%}">
                            </a>
                            {% } %}</td>
                            <td class="name">
                            <a href="{%=file.url%}" title="{%=file.name%}" data-gallery="{%=file.thumbnail_url&&'gallery'%}" download="{%=file.name%}">{%=file.name%}</a>
                            </td>
                            <td class="size"><span>{%=o.formatFileSize(file.size)%}</span></td>
                            <td colspan="2"></td>
                            {% } %}
                            <td class="delete">
                            </td>
                            </tr>
                            {% } %}
                        </script>
                    </div>

upload.aspx这边的js

$('#fileupload').fileupload({
                // Uncomment the following to send cross-domain cookies:
                //xhrFields: {withCredentials: true},
                url: 'uploadfile.ashx?Action=upload',
            });

            // Load existing files:
            // Demo settings:
            $.ajax({
                // Uncomment the following to send cross-domain cookies:
                //xhrFields: {withCredentials: true},
                url: $('#fileupload').fileupload('option', 'url'),
                context: $('#fileupload')[0],
                maxFileSize: 5000000,
                acceptFileTypes: /(\.|\/)(gif|jpe?g|png)$/i,
                process: [{
                        action: 'load',
                        fileTypes: /^image\/(gif|jpeg|png)$/,
                        maxFileSize: 20000000 // 20MB
                    }, {
                        action: 'resize',
                        maxWidth: 1440,
                        maxHeight: 900
                    }, {
                        action: 'save'
                    }
                ],
            }).done(function (result) {         
                $(this).fileupload('option', 'done')
                    .call(this, null, {
                    result: result
                });
            })

uploadfile.ashx后台

public class uploadfile1 : IHttpHandler
    {

        public void ProcessRequest(HttpContext context)
        {
            context.Response.Buffer = true;
            context.Response.ExpiresAbsolute = DateTime.Now.AddDays(-1);
            context.Response.AddHeader("pragma", "no-cache");
            context.Response.AddHeader("cache-control", "");
            context.Response.CacheControl = "no-cache";
            context.Response.ContentType = "text/plain";
            System.Collections.Specialized.NameValueCollection forms = context.Request.Form;
            HttpFileCollection files = context.Request.Files;
            int num = files.Count;
            string key = forms.Get("dKeyword");
            if (num > 0)
            {
                for (int i = 0; i < num; i++)
                {
                    HttpPostedFile file = files[i];
                    int fileSizeInBytes = file.ContentLength;
                    string filename = Path.GetFileNameWithoutExtension(file.FileName);
                }
            }
        }

        public bool IsReusable
        {
            get
            {
                return false;
            }
        }
    }

ashx这边已经可以 获取文件名 进行上传

但是如果ashx 不加context.Response.Write(“finished”); 插件这边就显示Empty file upload result
加了context.Response.Write(“finished”); 插件这边就显示SyntaxError: 无效字符

那么问题就是 ashx如何返回信息给插件 上传成功或者存在重名或者上传失败信息并在template-download里面显示呢？

[Go 旅城通票]

自己去看插件api，需要服务器端返回什么样的数据