js:大小转化b,kb,mb,gb

 /**
  * 文件大小换算
  * **/
conver(limit){
         var size = "";
         if (limit < 0.1 * 1024) { //如果小于0.1KB转化成B
           size = limit.toFixed(2) + "B";
         } else if (limit < 0.1 * 1024 * 1024) {//如果小于0.1MB转化成KB
           size = (limit / 1024).toFixed(2) + "KB";
         } else if (limit < 0.1 * 1024 * 1024 * 1024) { //如果小于0.1GB转化成MB
           size = (limit / (1024 * 1024)).toFixed(2) + "MB";
         } else { //其他转化成GB
           size = (limit / (1024 * 1024 * 1024)).toFixed(2) + "GB";
         }
         var sizestr = size + "";
         var len = sizestr.indexOf("\.");
         var dec = sizestr.substr(len + 1, 2);
         if (dec == "00") {//当小数点后为00时 去掉小数部分
           return sizestr.substring(0, len) + sizestr.substr(len + 3, 2);
         }
         return sizestr;
       }
  调用： var file_size = this.conver(this.fileInfo.size)