zzjtnb

# 如何使用正则表达式从下面的URL中提取字符串“ XMLFileName”
## 可以使用split()，pop()和replace() ...
```JavaScript
var x = "C:\\Documents and Settings\\Dig\\Desktop\\XMLFileName.xml";
var filename = x.split('\\').pop().replace(/\..+$/, '');
console.log(filename)
```
[jsbin](https://jsfiddle.net/h8uK6)

## 也可以使用单个正则表达式

zzjtnb

```css
input[type="search"]::-webkit-search-cancel-button {
      -webkit-appearance: none;
      height: 16px;
      width: 16px;
      background: url(https://yxs-web.oss-cn-beijing.aliyuncs.com/328e4d97f9d0d68ea04e872f68e508e3.png) no-repeat;
      background-size: contain;
    }
```
更改placeholder

zzjtnb

//统计数组中有多少个重复的单词：
// let counts = (arr, value) => arr.reduce((a, v) => v === value ? a + 1 : a + 0, 0);
// console.log('数组counts中"李"出现的次数是：' + counts(["李", "李", "设", "弟", "弟", "生", "生", "李"], "李"));
// 不用reduce时：
/**
 * 统计数组中有多少个重复的单词
 * @param {Array} array 待分页的数组
 * @return {Object}  统计后的对象
 */
function getRepeatNum(array) {

zzjtnb

# js
```JavaScript
let arr= [0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15]
function pagination (currentPage, pageSize, array) {
  const skipNum = (currentPage - 1) * pageSize;
  return (skipNum + pageSize >= array.length) ? array.slice(skipNum, array.length) : array.slice(skipNum, skipNum + pageSize)
}
console.log(pagination(2,4,arr))
```
# ts

zzjtnb

# Base64/hex
Base64与hex都是将二进制数据编码成字符串的编码方式，针对的是二进制字节而非字符串。
因此，要获得某个string的base64编码时，应该先得到string的二进制，再对二进制进行base6编码：
```JavaScript
// 编码
const str = '哈哈'
let b = Buffer.from(str) // b中存的是哈哈的utf8编码二进制
let base64Code = b.toString('base64') // '5ZOI5ZOI'
// 解码
const code = '5ZOI5ZOI'

zzjtnb

```JavaScript
const arr = [{id: 1, value : "value1", date: "2018-08-08", time: "15:27:17"},
{id: 2, value : "value2", date: "2018-08-09", time: "12:27:17"},
{id: 3, value : "value3", date: "2018-08-10", time: "17:27:17"},
{id: 4, value : "value4", date: "2018-08-10", time: "01:27:17"},
{id: 5, value : "value5", date: "2018-08-10", time: "09:27:17"},
{id: 6, value : "value6", date: "2018-08-10", time: "23:27:17"},
{id: 7, value : "value7", date: "2018-08-10", time: "16:27:17"},
{id: 8, value : "value8", date: "2018-08-11", time: "10:27:17"}
];

zzjtnb

# 第一种
```JavaScript
const fs = require('fs')
const path = require('path');

/**
 * 遍历目录里面的所有文件和目录 (同步)
 * @param {String} dir        目录名
 * @param {Function} callback  找到一个文件时的回调
 */

zzjtnb

# 同步遍历
```JavaScript
const fs = require('fs');
const path=require('path');
function travel(dir,callback){
    fs.readdirSync(dir).forEach((file)=>{
        var pathname=path.join(dir,file)
        if(fs.statSync(pathname).isDirectory()){
            travel(pathname,callback)
        }else{

zzjtnb

# 课程介绍

正处于春招的黄金时期，为了帮助大家找到更好的工作，更快的找到工作。组织本次的专项课程。

今日的课程主题是 **项目**，会讲到公司项目研发的流程。

zzjtnb

```bash
::定时关机脚本
::Author:Tony Chang 
::2016.10.18
::原创代码，转载请注明出处
@echo off
mode con lines=25
setlocal enabledelayedexpansion
title 定时关机
color 0a