js之上传文件多图片预览

多图片上传预览功能也是现在非常常用的

下面是html代码:

<html xmlns="http://www.w3.org/1999/xhtml">

<head>

<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />

<title>测试页面</title>

<script type="text/javascript">

    //下面用于多图片上传预览功能

    function setImagePreviews(avalue) {

        var docObj = document.getElementById("doc");

        var dd = document.getElementById("dd");

        dd.innerHTML = "";

        var fileList = docObj.files;

        for (var i = 0; i < fileList.length; i++) {            



            dd.innerHTML += "<div style='float:left' > <img id='img" + i + "'  /> </div>";

            var imgObjPreview = document.getElementById("img"+i); 

            if (docObj.files && docObj.files[i]) {

                //火狐下，直接设img属性

                imgObjPreview.style.display = 'block';

                imgObjPreview.style.width = '150px';

                imgObjPreview.style.height = '180px';

                //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[i]);

            }

            else {

                //IE下，使用滤镜

                docObj.select();

                var imgSrc = document.selection.createRange().text;

                alert(imgSrc)

                var localImagId = document.getElementById("img" + i);

                //必须设置初始大小

                localImagId.style.width = "150px";

                localImagId.style.height = "180px";

                //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>

</head>



<body>

<div style="margin :0px auto; width:990px;">

<input type="file"  name="file" id="doc" multiple="multiple"  style="width:150px;" onchange="javascript:setImagePreviews();" accept="image/*" />

<div id="dd" style=" width:990px;"></div>

</div>

</body>

</html>