详细分析HTML5 FormData对象的使用

var oMyForm = new FormData();oMyForm.append("username", "Groucho");oMyForm.append("accountnum", 123456); // 数字123456被立即转换成字符串"123456"// fileInputElement中已经包含了用户所选择的文件oMyForm.append("userfile", fileInputElement.files[0]);var oFileBody = "<a id="a"><b id="b">hey!</b></a>"; // Blob对象包含的文件内容var oBlob = new Blob([oFileBody], { type: "text/xml"});oMyForm.append("webmasterfile", oBlob);var oReq = new XMLHttpRequest();oReq.open("POST", "http://foo.com/submitform.php");oReq.send(oMyForm);

var newFormData = new FormData(someFormElement);

var formElement = document.getElementById("myFormElement");var oReq = new XMLHttpRequest();oReq.open("POST", "submitform.php");oReq.send(new FormData(formElement));

var formElement = document.getElementById("myFormElement");formData = new FormData(formElement);formData.append("serialnumber", serialNumber++);oReq.send(formData);

<form enctype="multipart/form-data" method="post" name="fileinfo">  <label>Your email address:</label>  <input type="email" autocomplete="on" autofocus name="userid" placeholder="email" required size="32" maxlength="64" /><br />  <label>Custom file label:</label>  <input type="text" name="filelabel" size="12" maxlength="32" /><br />  <label>File to stash:</label>  <input type="file" name="file" required /></form><p id="output"></p><a href="javascript:sendForm()">Stash the file!</a>

function sendForm() {  var oOutput = document.getElementById("output");  var oData = new FormData(document.forms.namedItem("fileinfo"));  oData.append("CustomField", "This is some extra data");  var oReq = new XMLHttpRequest();  oReq.open("POST", "stash.php", true);  oReq.onload = function(oEvent) {    if (oReq.status == 200) {      oOutput.innerHTML = "Uploaded!";    } else {      oOutput.innerHTML = "Error " + oReq.status + " occurred uploading your file.<br \/>";    }  };  oReq.send(oData);}

data.append("myfile", myBlob);

var fd = new FormData(document.getElementById("fileinfo"));fd.append("CustomField", "This is some extra data");$.ajax({  url: "stash.php",  type: "POST",  data: fd,  processData: false,  // 告诉jQuery不要去处理发送的数据  contentType: false   // 告诉jQuery不要去设置Content-Type请求头});