js上传图片预览 

<!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>

 本文转自：http://blog.csdn.net/benben0503/article/details/17964207

posted @ 2014-09-26 10:25  彼岸的命運╰＇  阅读(160)  评论(0)  编辑  收藏  举报