代码：（demo33.jsp）
<%@ page contenttype="text/html;charset=utf-8" language="java" %> <html> <head> <title>demo33.jsp</title> </head> <body> <label for="text">名称</label> <input type="text" id="text" name="name"/> <label for="file">文件</label> <input type="file" id="file" name="file"/> <button type="button" onclick="ajaxuploadfile()">确定</button> </body> <script type="text/javascript"> function ajaxuploadfile() { var formdata = new formdata(); var xmlhttp; if (window.xmlhttprequest) {// code for ie7+, firefox, chrome, opera, safari xmlhttp = new xmlhttprequest(); }else {// code for ie6, ie5 xmlhttp = new activexobject("microsoft.xmlhttp"); } xmlhttp.open("post","/data",true); xmlhttp.setrequestheader("x-requested-with", "xmlhttprequest"); formdata.append("name",document.getelementbyid("text").value); formdata.append("file",document.getelementbyid("file").files[0]); xmlhttp.send(formdata); xmlhttp.onreadystatechange=function() { if (xmlhttp.readystate==4) { if (xmlhttp.status==200) { console.log("上传成功"+xmlhttp.responsetext); }else { console.log("上传失败"+xmlhttp.responsetext); } } } } </script> </html>
以上就是原生js实现文件异步上传的方法的详细内容。