JavaScript 大小转化B KB MB GB等的转化

当我们知道B字节时，转化成KB MB GB 等等

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;
	}