13.3.8 sort方法.html

javascript即用即差核心对象手册

<script>
   var arr=new Array(2,5,3,20,1,"b","x","B","X");
   writeArr("排序前",arr);
   writeArr("升序排列",arr.sort());
   writeArr("降序排列,字母不分大小写",arr.sort(desc));
   writeArr("严格降序排列",arr.sort(desc1));
   //自定义函数输出提示信息和数组元素
   function writeArr(str,array)
   {
      document.write(str+":");
	  document.write(array.join(","));
	  document.write("<br>");
   }
   //按降序排列,字母不区分大小写
   function desc(a,b)
   {
      var a=new String(a);
	  var b=new String(b);
	  //如果a大于b，则返回－1，所以a排在前b派在后
	  return -1*a.localeCompare(b) ;
   }
   //严格降序
   function desc1(a,b)
   {
         var stra=new String(a);
	     var strb=new String(b);
		 var ai=stra.charCodeAt(0);
		 var bi=strb.charCodeAt(0);
		 if( ai>bi )
		   return -1;
		 else
		   return 1;
   }
</script>