JavaScript 数组内容的反转

var arr = [1,6,5,7,9,10,11]
var len = arr.length-1;
for(i=0;i<len/2;i++){
var temp = arr[i];
arr[i] = arr[len-i]
arr[len-i] = temp;
}
document.write(arr.join(","));

//反转 arr = [9,4,6,3,1]
var temp = arr[arr.length - 1];//数组的最后一个数
arr[arr.length - 1] = arr[0];
arr[0] = temp;  //首尾交换位置

var temp2 = arr[arr.length - 2];
arr[arr.length - 2] = arr[1];
arr[1] = temp2;

var temp3 = arr[arr.length - 3];
arr[arr.length - 3] = arr[2];
arr[2] = temp3;