JS大小轉化B KB MB GB的轉化方法

    function conver(limit){  
            var size = "";  
            if( limit < 0.1 * 1024 ){ //如果小於0.1KB轉化成B  
                size = limit.toFixed(2) + "B";    
            }else if(limit < 0.1 * 1024 * 1024 ){//如果小於0.1MB轉化成KB  
                size = (limit / 1024).toFixed(2) + "KB";              
            }else if(limit < 0.1 * 1024 * 1024 * 1024){ //如果小於0.1GB轉化成MB  
                size = (limit / (1024 * 1024)).toFixed(2) + "MB";  
            }else{ //其他轉化成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"){//當小數點后為00時 去掉小數部分  
                return sizestr.substring(0,len) + sizestr.substr(len + 3,2);  
            }  
            return sizestr;  
        }