JS大小转化B KB MB GB的转化方法

    function 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;
        }