<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Html5 Ajax 上传文件</title>
<style type="text/css">
#imgshow{
width: 500px;
height: 300px
}
</style>
<script type="text/javascript">
function UpladFile() {
var fileObj = document.getElementById("file").files[0]; // js 获取文件对象
var FileController = "aa.php"; // 接收上传文件的后台地址
// FormData 对象
var form = new FormData();
form.append("author", "hooyes"); // 可以增加表单数据
form.append("file", fileObj); // 文件对象
// XMLHttpRequest 对象
var xhr = new XMLHttpRequest();
xhr.open("post", FileController, true);
xhr.onload = function () {
// alert("上传完成!");
};
xhr.upload.addEventListener("progress", progressFunction, false);
xhr.send(form);
}
function changeimg(){
var fileObj = document.getElementById("file").files[0]; // js 获取文件对象
var srcs = getObjectURL(fileObj); //获取路径
document.getElementById("imgshow").src=srcs
}
function progressFunction(evt) {
var progressBar = document.getElementById("progressBar");
var percentageDiv = document.getElementById("percentage");
if (evt.lengthComputable) {
progressBar.max = evt.total;
progressBar.value = evt.loaded;
percentageDiv.innerHTML = Math.round(evt.loaded / evt.total * 100) + "%";
}
}
function getObjectURL(file) {
var url = null;
if (window.createObjectURL != undefined) {
url = window.createObjectURL(file)
} else if (window.URL != undefined) {
url = window.URL.createObjectURL(file)
} else if (window.webkitURL != undefined) {
url = window.webkitURL.createObjectURL(file)
}
return url
};
</script>
</head>
<body>
<span id="percentage"></span>
<br />
<input type="file" onchange="changeimg()" id="file" name="myfile" />
<input type="button" onclick="UpladFile()" value="上传" />
<div>
<img src="#" id="imgshow">
</div>
</body>
</html>
直接在aa.php里面打印就可以了
原文：https://www.cnblogs.com/ayanboke/p/11401925.html