JS数组获取最大值、最小值及长度的实现方法

//最小值
Array.prototype.min = function() {
var min = this[0];
var len = this.length;
for (var i = 1; i < len; i++){
if (this[i] < min){
min = this[i];
}
}
return min;
}
//最大值
Array.prototype.max = function() {
var max = this[0];
var len = this.length;
for (var i = 1; i < len; i++){
if (this[i] > max) {
max = this[i];
}
}
return max;
}
//数组长度
var array = new array(1,2,3,2,4,55,2);
alert(array.length);//输出7