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<html xmlns="http://www.w3.org/1999/xhtml"><head><meta name="DEscription" contect="my code demo" /><meta name="Author" contect="Michael@jb51.net" /><meta http-equiv="Content-Type" content="text/html; charset=utf-8" /><meta http-equiv="X-UA-Compatible" content="IE=emulateIE8"><title>js check file size @ jb51.net</title></head><body>< img id="tempimg" dynsrc="" src="" style="display:none" /><input type="file" name="file" id="fileuploade" size="40" /><input type="button" name ="check" value="checkfilesize" οnclick="checkfile()"/></body><script type="text/javascript">var maxsize = 210241024;//2Mvar errMsg = "上传的附件文件不能超过2M！！！";var tipMsg = "您的浏览器暂不支持计算上传文件的大小，确保上传文件不要超过2M，建议使用IE、FireFox、Chrome浏览器。";var browserCfg = {};var ua = window.navigator.userAgent;if (ua.indexOf("MSIE")>=1){browserCfg.ie = true;}else if(ua.indexOf("Firefox")>=1){browserCfg.firefox = true;}else if(ua.indexOf("Chrome")>=1){browserCfg.chrome = true;}function checkfile(){try{var obj_file = document.getElementById("fileuploade");if(obj_file.value""){alert("请先选择上传文件");return;}var filesize = 0;if(browserCfg.firefox || browserCfg.chrome ){filesize = obj_file.files[0].size;}else if(browserCfg.ie){var obj_img = document.getElementById('tempimg');obj_img.dynsrc=obj_file.value;filesize = obj_img.fileSize;alert(filesize);}else{alert(tipMsg);return;}if(filesize-1){alert(tipMsg);return;}else if(filesize>maxsize){alert(errMsg);return;}else{alert("文件大小符合要求");alert(filesize);return;}}catch(e){alert(e);}}</script></html>
