js数组排序—自定义快速排序

		var arr = [3, 4, 2, 1];
		arr.sort();
		console.log(arr);

(4) [1, 2, 3, 4]

		arr.sort(function(val1, val2){ 
   
			//return val1 - val2; 默认
			return val2 - val1;//倒序。根据结果大于0、小于0、等于零做判断
		});

		var arr = [{ 
   "a":1},{ 
   "a":311},{ 
   "a":2}];
		arr.sort(function(val1, val2){ 
   
			return val2.a - val1.a;
		});
		console.log(arr);

Array.prototype.sortq = function(_compare){ 
   
	
	var _this = this;
	if(this.length == 0)
		return;			

	var compare = _compare || function(val1, val2){ 
   
		return val1 - val2 > 0 ? false : true;
	};
	
	function quickSort(src){ 
   
		_quickSort(src, 0, src.length - 1);
	}
	
	function _quickSort(src, left, right){ 
   
		
		var key = src[left];
		var keyIndex = left;
		var i = left;
		var j = right;
		while(i < j){ 
   
			
			while(i < j){ 
   
				if(compare(_this[j], _this[keyIndex])){ 
   
					src[keyIndex] = src[j];
					src[j] = key;
					keyIndex = j;
					break;
				}
				j--;
				
			}
			
			while(i < j){ 
   
				if(compare(_this[keyIndex], _this[i])){ 
   
					src[keyIndex] = src[i];
					src[i] = key;
					keyIndex = i;
					break;
				}
				i++;
				
			}
			
		}
		
		if(left != right){ 
   
			if(keyIndex != left)
				_quickSort(src, left, keyIndex - 1);
			if(keyIndex != right)
				_quickSort(src, keyIndex + 1, right);
		}	
		
	}
	
	quickSort(this);
}

		var arr1 = new Array();
		for(var i = 0; i < 1000000; i++)
			arr1.push(Math.random());
		var dat1 = new Date();
		arr1.sort();
		var dat2 = new Date();
		console.log(dat2.getTime() - dat1.getTime());

		var arr2 = new Array();
		for(var i = 0; i < 1000000; i++)
			arr2.push(Math.random());
		var dat3 = new Date();
		arr2.sortq();
		var dat4 = new Date();
		console.log(dat4.getTime() - dat3.getTime());

7237
292

		var arr3 = new Array();
		for(var i = 0; i < 40; i++){ 
   
			arr3.push(
				{ 
   
					aa: Math.random()
				}
			);
		}
		
		arr3.sortq(function(val1, val2){ 
   
			return val1.aa - val2.aa > 0 ? false : true;
		});
		
		console.log(arr3);