筆試題遇到的,百度了許多資料,但是原地址的給的有問題,window.URL.createObjectURL(dFile.files[0]);
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>JS上傳圖片前的圖片預覽效果</title>
</head>
<body>
<input id="myfile" type="file" />
<br />
<img src="img/01.jpg" alt="Image to be upload." />
<div id="info"></div>
<script type="text/javascript">
var dFile = document.getElementById('myfile');
var dImg = document.getElementsByTagName('img')[0];
var dInfo = document.getElementById('info');
dFile.onchange = function(){
if(!dFile.value.match(/.jpg|.gif|.png|.bmp/i)){alert('File type must be: .jpg, .gif, .bmp or .png !');return;}
if(dFile.files){
// dImg.src = dFile.files[0].getAsDataURL(); ff不支持啦
dImg.src = window.URL.createObjectURL(dFile.files[0]);
}else if(dFile.value.indexOf('') > -1 || dFile.value.indexOf('/') > -1){
dImg.src = dFile.value;
}
console.log(dFile.value)
}
</script>
</body>
</html>