1.创建数组
var arr = new Array();
var arr = [];
var arr1 = [1, 2, 'pink老师', true];
2.数组的用法
1.遍历数组
var arr = ['red', 'green', 'blue'];
for (var i = 0; i < 3; i++) {
console.log(arr[i]);
}
2.求数组长度
3.数组转成字符串
var arr = ['red', 'green', 'blue', 'pink'];
var str = '';
var sep = '*';
for (var i = 0; i < arr.length; i++) {
str += arr[i] + sep;
}
4.新增数组元素
- 通过修改length长度来实现数组扩容,length属性是可读写的
var arr = ['red', 'green', 'blue'];
console.log(arr.length);
arr.length = 5;
console.log(arr);
console.log(arr[3]);
console.log(arr[4]);
var arr1 = ['red', 'green', 'blue'];
arr1[3] = 'pink';
console.log(arr1);
arr1[4] = 'hotpink';
console.log(arr1);
arr1[0] = 'yellow';
console.log(arr1);
arr1 = '有点意思';
console.log(arr1);
5.数组去重案例
var arr = [2, 0, 6, 1, 77, 0, 52, 0, 25, 7];
var newArr = [];
for (var i = 0; i < arr.length; i++) {
if (arr[i] != 0) {
newArr[newArr.length] = arr[i];
}
}
6.翻转数组案例
var arr = ['red', 'green', 'blue', 'pink', 'purple', 'hotpink'];
var newArr = [];
for (var i = arr.length - 1; i >= 0; i--) {
newArr[newArr.length] = arr[i]
}
7.冒泡排序
var arr = [4, 1, 2, 3, 5];
var temp;
for (var i = 0; i < arr.length - 1; i++)
for (var j = i + 1; j < arr.length; j++) {
if (arr[j - 1] > arr[j]) {
temp = arr[j - 1];
arr[j - 1] = arr[j];
arr[j] = temp;
}
}