上传图片之上传前预览图片

[javascript] view plaincopy在CODE上查看代码片派生到我的代码片

< script type="text/javascript">  
        function setImagePreview(docObj,localImagId,imgObjPreview)   
        {  
            if(docObj.files && docObj.files[0])  
            {  
                //火狐下，直接设img属性  
                imgObjPreview.style.display = 'block';  
                imgObjPreview.style.width = '300px';  
                imgObjPreview.style.height = '200px';                      
  
  
                //火狐7以上版本不能用上面的getAsDataURL()方式获取，需要一下方式    
                imgObjPreview.src = window.URL.createObjectURL(docObj.files[0]);  
            }  
            else  
            {  
                //IE下，使用滤镜  
                docObj.select();  
                var imgSrc = document.selection.createRange().text;  
                  
                //必须设置初始大小  
                localImagId.style.width = "300px";  
                localImagId.style.height = "200px";  
                  
                //图片异常的捕捉，防止用户修改后缀来伪造图片  
                try  
                {  
                    localImagId.style.filter="progid:DXImageTransform.Microsoft.AlphaImageLoader(sizingMethod=scale)";  
                    localImagId.filters.item("DXImageTransform.Microsoft.AlphaImageLoader").src = imgSrc;  
                 }  
                 catch(e)  
                 {  
                    alert("您上传的图片格式不正确，请重新选择!");  
                    return false;  
                  }                            
                  imgObjPreview.style.display = 'none';  
                  document.selection.empty();  
            }  
            return true;  
        }  
< /script> 

[html] view plaincopy在CODE上查看代码片派生到我的代码片

<div id="localImag"  style="width: 300px; height: 200px">  
   <img id="preview" alt="预览图片" src="../../Images/noImage.gif" width="300px" height="200px" />  
</div>  
<asp:FileUpload ID="PicLoad" Width="300px" runat="server" onchange="javascript:setImagePreview(this,localImag,preview);"><span style="font-family: Arial, Helvetica, sans-serif;"></asp:FileUpload></span>