No more nonsense, I will just post the js code for you. The specific code is as follows:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html> <head> <title></title> </head> <body> <div id="divPreview"> <img src="/static/imghwm/default1.png" data-src="noperson.jpg" class="lazy" id="imgHeadPhoto" style="max-width:90%" alt="" /> </div> <input type="file" onchange="PreviewImage(this,'imgHeadPhoto','divPreview');" size="20" /> <script type="text/javascript"> //js本地图片预览,兼容ie[6-9]、火狐、Chrome17+、Opera11+、Maxthon3 function PreviewImage(fileObj, imgPreviewId, divPreviewId) { var allowExtention = ".jpg,.bmp,.gif,.png"; //允许上传文件的后缀名document.getElementById("hfAllowPicSuffix").value; var extention = fileObj.value.substring(fileObj.value.lastIndexOf(".") + 1).toLowerCase(); var browserVersion = window.navigator.userAgent.toUpperCase(); if (allowExtention.indexOf(extention) > -1) { if (fileObj.files) {//HTML5实现预览,兼容chrome、火狐7+等 if (window.FileReader) { var reader = new FileReader(); reader.onload = function (e) { document.getElementById(imgPreviewId).setAttribute("src", e.target.result); } reader.readAsDataURL(fileObj.files[0]); } else if (browserVersion.indexOf("SAFARI") > -1) { alert("不支持Safari6.0以下浏览器的图片预览!"); } } else if (browserVersion.indexOf("MSIE") > -1) { if (browserVersion.indexOf("MSIE 6") > -1) {//ie6 document.getElementById(imgPreviewId).setAttribute("src", fileObj.value); } else {//ie[7-9] fileObj.select(); if (browserVersion.indexOf("MSIE 9") > -1) fileObj.blur(); //不加上document.selection.createRange().text在ie9会拒绝访问 var newPreview = document.getElementById(divPreviewId + "New"); if (newPreview == null) { newPreview = document.createElement("div"); newPreview.setAttribute("id", divPreviewId + "New"); newPreview.style.width = document.getElementById(imgPreviewId).width + "px"; newPreview.style.height = document.getElementById(imgPreviewId).height + "px"; newPreview.style.border = "solid 1px #d2e2e2"; } newPreview.style.filter = "progid:DXImageTransform.Microsoft.AlphaImageLoader(sizingMethod='scale',src='" + document.selection.createRange().text + "')"; var tempDivPreview = document.getElementById(divPreviewId); tempDivPreview.parentNode.insertBefore(newPreview, tempDivPreview); tempDivPreview.style.display = "none"; } } else if (browserVersion.indexOf("FIREFOX") > -1) {//firefox var firefoxVersion = parseFloat(browserVersion.toLowerCase().match(/firefox\/([\d.]+)/)[1]); if (firefoxVersion < 7) {//firefox7以下版本 document.getElementById(imgPreviewId).setAttribute("src", fileObj.files[0].getAsDataURL()); } else {//firefox7.0+ document.getElementById(imgPreviewId).setAttribute("src", window.URL.createObjectURL(fileObj.files[0])); } } else { document.getElementById(imgPreviewId).setAttribute("src", fileObj.value); } } else { alert("仅支持" + allowExtention + "为后缀名的文件!"); fileObj.value = ""; //清空选中文件 if (browserVersion.indexOf("MSIE") > -1) { fileObj.select(); document.selection.clear(); } fileObj.outerHTML = fileObj.outerHTML; } return fileObj.value; //返回路径 } </script> </body> </html>
The above is the JS implementation of the image upload preview function introduced by the editor

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