图片上传本地预览

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
        <body>
                <input type=file name="doc" id="doc" onchange="javascript:setImagePreview();">
<p>
<div id="localImag"><img id="preview" width=-1 height=-1 style="diplay:none" /></div>
</p>
<script>
function setImagePreview() {
        var docObj=document.getElementById("doc");
 
        var imgObjPreview=document.getElementById("preview");
                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 = '120px';
                        //imgObjPreview.src = docObj.files[0].getAsDataURL();
      //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;
                        var localImagId = document.getElementById("localImag");
                        //必须设置初始大小
                        localImagId.style.width = "300px";
                        localImagId.style.height = "120px";
                        //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>
</body>
</html>

 

posted @ 2015-12-16 15:29  诸葛风流  阅读(277)  评论(0编辑  收藏  举报