上传图片时JS自动显示图片

<HTML> <META http-equiv=Content-Type content="text/html; charset=gb2312"> <HEAD> <TITLE>javascript 图片预览</TITLE> </HEAD> <BODY> <script> function preview(imgFile,num) { //预览代码，支持 IE6、IE7。 var newPreview = document.getElementById("preview1"); var t ; if(document.all) //IE t = imgFile.value; else t = imgFile.files[0].getAsDataURL(); //FF newPreview.style.backgroundImage = "url(" + t + ")";//imgFile.value; newPreview.style.width = "108px"; newPreview.style.height = "130px"; newPreview.style.display = "block"; } </script> <input type="file" onchange='ShowImg(this)' /> <script>function ShowImg(o) { //var Browser_Agent=navigator.userAgent; //if(Browser_Agent.indexOf("Firefox")!=-1) //{ //火狐使用 // document.getElementById("idImg").src=o.files[0].getAsDataURL(); // document.getElementById("idImg").style.display = "block"; // } //else //{ preview(o,1); //} } </script> </BODY> </HTML>
[Ctrl+A 全选 注:如需引入外部Js需刷新才能执行]