js判断文件格式及大小

 

 
//判断照片大小
function getPhotoSize(obj){
    photoExt=obj.value.substr(obj.value.lastIndexOf(".")).toLowerCase();//获得文件后缀名
    if(photoExt!='.jpg'){
        alert("请上传后缀名为jpg的照片!");
        return false;
    }
    var fileSize = 0;
    var isIE = /msie/i.test(navigator.userAgent) && !window.opera;           
    if (isIE && !obj.files) {         
         var filePath = obj.value;           
         var fileSystem = new ActiveXObject("Scripting.FileSystemObject");  
         var file = fileSystem.GetFile (filePath);              
         fileSize = file.Size;        
    }else 
         fileSize = obj.files[0].size;    
    }
    fileSize=Math.round(fileSize/1024*100)/100; //单位为KB
    if(fileSize>=10){
        alert("照片最大尺寸为10KB,请重新上传!");
        return false;
    }
}


jsp页面:

<input type="file" id="imgFile" name="upload" style="150px;" onchange="getPhotoSize(this)"/>
原文地址:https://www.cnblogs.com/xzzzys/p/7778323.html