实现上传图片预览

<title>图片上传预览</title>
<input type="file" id="fileElem" multiple accept="image/*"  onchange="handleFiles(this)">
<div id="fileList" style="200px;height:200px;"></div>
<script>
	window.URL = window.URL || window.webkitURL;
	var fileElem = document.getElementById("fileElem"),
	    fileList = document.getElementById("fileList");
	function handleFiles(obj) {
		var files = obj.files,
			img = new Image();
		if(window.URL){
			//File API
			  //alert(files[0].name + "," + files[0].size + " bytes");
		      img.src = window.URL.createObjectURL(files[0]); //创建一个object URL，并不是你的本地路径
		      img.width = 200;
		      img.onload = function(e) {
		         window.URL.revokeObjectURL(this.src); //图片加载后，释放object URL
		      }
		      fileList.appendChild(img);
		}else if(window.FileReader){
			//opera不支持createObjectURL/revokeObjectURL方法。我们用FileReader对象来处理
			var reader = new FileReader();
			reader.readAsDataURL(files[0]);
			reader.onload = function(e){
				//alert(files[0].name + "," +e.total + " bytes");
				img.src = this.result;
				img.width = 200;
				fileList.appendChild(img);
			}
		}else{
			//ie
			obj.select();
			obj.blur();
			var nfile = document.selection.createRange().text;
			document.selection.empty();
			img.src = nfile;
			img.width = 200;
			img.onload=function(){
		     // alert(nfile+","+img.fileSize + " bytes");
		    }
			fileList.appendChild(img);
			//fileList.style.filter="progid:DXImageTransform.Microsoft.AlphaImageLoader(sizingMethod='image',src='"+nfile+"')";
		}
	}
</script>

　　使用smartUpload组件上传文件时的包：jsmartcom_zh_CN.jar