funUploadFile : function(file){
var self = this; // 在each中this指向没个v 所以先将this保留
var formdata = new FormData();
formdata.append("index", file.index);
formdata.append("fileList", file);
var xhr = new XMLHttpRequest();
if ("withCredentials" in xhr) {
// XHR for Chrome/Firefox/Opera/Safari.
xhr.open("POST", self.url, true);
} else if (typeof XDomainRequest != "undefined") {
// XDomainRequest for IE.
xhr = new XDomainRequest();
xhr.open("POST", self.url);
} else {
xhr = null;
}
// 绑定上传事件
// 进度
xhr.upload.addEventListener('progress', function (e) {
if (e.lengthComputable) {
// 回调到外部
self.onProgress(file, e.loaded, e.total);
}
}, false);
// 完成
xhr.addEventListener("load", function(e){
// 从文件中删除上传成功的文件 false是不执行onDelete回调方法
self.funDeleteFile(file.index, false);
// 回调到外部
self.onSuccess(file, xhr.responseText);
if(self.uploadFile.length == 0){
// 回调全部完成方法
self.onComplete("全部完成");
}
}, false);
xhr.addEventListener("error", function(e){
// 回调到外部
self.onFailure(file, xhr.responseText);
}, false);
//xhr.setRequestHeader("Access-Control-Allow-Origin", "*");
//xhr.setRequestHeader("X-Requested-With", "XMLHttpRequest");
//xhr.setRequestHeader("Content-Type", "multipart/form-data");
xhr.send(formdata);
//xhr.send();
}
上述提交的html表单类似于：<form id="uploadForm" action="http://fileserver.bbb.com/fileserver.ashx?action=upload&aid=1" method="post" enctype="multipart/form-data">
后台配置：
<system.webServer>
<httpProtocol>
<customHeaders>
<add name="Access-Control-Allow-Origin" value="*" />
<add name="Access-Control-Allow-Headers" value="X-Requested-With,Content-Type" />
<add name="Access-Control-Allow-Methods" value="GET, POST, PUT, DELETE, OPTIONS" />
</customHeaders>
</httpProtocol>
<handlers>
<remove name="WebDAV" />
<remove name="ExtensionlessUrlHandler-ISAPI-4.0_32bit" />
<remove name="ExtensionlessUrlHandler-ISAPI-4.0_64bit" />
<remove name="ExtensionlessUrlHandler-Integrated-4.0" />
<add name="ExtensionlessUrlHandler-ISAPI-4.0_32bit" path="*." verb="GET,HEAD,POST,DEBUG,PUT,DELETE,PATCH,OPTIONS" modules="IsapiModule" scriptProcessor="%windir%\Microsoft.NET\Framework\v4.0.30319\aspnet_isapi.dll" preCondition="classicMode,runtimeVersionv4.0,bitness32" responseBufferLimit="0" />
<add name="ExtensionlessUrlHandler-ISAPI-4.0_64bit" path="*." verb="GET,HEAD,POST,DEBUG,PUT,DELETE,PATCH,OPTIONS" modules="IsapiModule" scriptProcessor="%windir%\Microsoft.NET\Framework64\v4.0.30319\aspnet_isapi.dll" preCondition="classicMode,runtimeVersionv4.0,bitness64" responseBufferLimit="0" />
<add name="ExtensionlessUrlHandler-Integrated-4.0" path="*." verb="GET,HEAD,POST,DEBUG,PUT,DELETE,PATCH,OPTIONS" type="System.Web.Handlers.TransferRequestHandler" preCondition="integratedMode,runtimeVersionv4.0" />
<add name="handler" path="handler.ashx" verb="*" type="WebApp.handler"/>
<remove name="OPTIONSVerbHandler" />
</handlers>
<modules runAllManagedModulesForAllRequests="true">
<remove name="WebDAVModule" />
</modules>
</system.webServer>
用handler后台处理：
namespace WebApp
{
/// <summary>
/// handler 的摘要说明
/// </summary>
public class handler : IHttpHandler
{
private HttpRequest _request;
private HttpResponse _response;
private HttpContext _context;
public void ProcessRequest(HttpContext context)
{
_context = context;
_request = context.Request;
_response = context.Response;
var action = context.Request.QueryString["action"];
switch (action)
{
case "upload":
Upload();
break;
default:
break;
}
}
private void Upload()
{
if (_request.Files.Count > 0)
{
}
_response.Write("aa:"+"xxx");
}
public bool IsReusable
{
get
{
return false;
}
}
}
}
在跨域请求的过程中一共请求了两次，第一次是一个叫做preflight的options请求，发送给服务器让服务器确认是否接受跨域请求，然后返回给浏览器确认，然后进行第二次真正的请求。如下图所示：
