**Xiang Wang @ 2015-11-23 18:56:23**

[火狐官方文档][官网]  
[对象基础][对象基础文档]  


# [typescript](./typescript/README.md)

# [Guide](guide导览.md)

# [Promise](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Using_promises)
```
// test/promise_wait.js
function test() {
  return axios.get(
    "https://httpbin.org/get"
  ).then(res=>{
    console.info("返回了数据")
    console.info(res.data)
    return res.data
  })
}
async function await_promise() {
  let prom = test()
  await prom
  console.info("请求执行完毕, 我才会输出, 但是需要用在async的函数里")
}
function main() {
  test().then(res=>{
    console.info("来了")
  })
  console.info("请求没执行完毕, 我会先输出")
}
```

# [内置对象](./build_in_objects内置对象.md)
Standard built-in objects 

## [Array数组](./array.md)

* Boolean
*返回一个数的布尔值*
0, -0, null, false, Nan, undefined, ""会变成false, 其他都是true(包括`{}`和`[]`)
* Date

## [Math][Math]
* [Math.floor][Math.floor]  
返回的是小于等于这个数字的最大整数
```
Math.floor(null) = 0;
Math.floor(-5.05) = -6;
```
返回一个数字的divmod, 不支持负数
```
var quotient = Math.floor(y/x);
var remainder = y % x;
```
* [Math.round](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Math/round)  
只能返回一个整数,和python不同

## [Number](./build_in_objects内置对象.md#number)
* [isInteger](https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Number/isInteger) 返回一个数字是不是整数
```
Number.isInteger(0.1)  // false
Number.isInteger("10")  // false
Number.isInteger([1])  // false
Number.isInteger(0)  // true
```

* 转化成大写数字  
[官网](https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/Intl/NumberFormat#%E4%BD%BF%E7%94%A8_locales)
```

// 通过编号系统中的 nu 扩展键请求，例如：中文十进制数字
console.log(new Intl.NumberFormat("zh-Hans-CN-u-nu-hanidec").format(number));
// → 一二三,四五六.七八九
```

* Object
* ## [RegExp](./build_in_objects内置对象.md)
* [String](./build_in_objects内置对象.md#String)

# [操作符号，表达式][expression]
Expressions and operators 

* [in][in]  
you must use index instead of value for a list, so the `in` operator means has property or not, it doesn't means the object contains the item
  ```
  obj = {'key': 'value'}
  'key' in obj  // true
  list = ['a', 'b', 'c']
  1 in list  // true
  3 in list  // false
  'a' in list  // false
  ```

### `...` [spread syntax](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Spread_syntax)  [展开语法](https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Operators/Spread_syntax)
用在列表上
```javascript
function sum(x, y, z) {
    return x + y + z
}
numbers = [1,2,3]
sum(...numbers)
[0, ...numbers, 4]
```
用在字典上, 后面的会替换掉前面的
```
const obj1 = { foo: "bar", x: 42 };
const obj2 = { foo: "baz", y: 13 };

const mergedObj = { x: 41, ...obj1, ...obj2, y: 9 }; // { x: 42, foo: "baz", y: 9 }
```

## [逻辑操作][逻辑操作]  
Logical Operators 
* `&&` and
* `||` or
* `!` not

## [执行顺序 *Operator precedence*][执行顺序]
* 20. (...)
* 16. ! ...
* 12. ... < ...
* 11. != !== == ===
* 6. ... && ...
* 5. ... || ...


# [语法](statements_and_declarations语法.md)
*Statements & declarations*

* do...while
这个和while相比, 能保证执行一次.
```
    do {
    } whilte (condition);
```
* ## const
* ## continue
* ## for
* ## [for of](./statements_and_declarations语法.md#for...of)
* ## for in
* ## function
* ## switch
* ## try...catch

# [Functions函数](./functions函数.md)

# [Misc](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Template_literals) 
* [template literals 字符串模板](./build_in_objects内置对象.md#String字符串)

待处理

# [webapi](./webapi/webapi.md)
atob, btoa

## [Element](./webapi/element.md)

## [GlobalEventHandlers](./webapi/README.md)
* ### onkeydown

## WebSocket API

## [console](./webapi/webapi.md#console)

## Window
* properties
    * [localStorage][localStorage]: 返回本地存储只能保存字符串。不存在返回null
    ```
    localStorage.setItem("myCat", "Tom");
    localStorage.getItem("myCat")  // 
    ```
    * location *返回一个Location对象*
        * 访问新的页面: location = "https://www.mozilla.org";
        * 刷新页面 location.reload(true);
* Methods
    * [confirm](https://developer.mozilla.org/en-US/docs/Web/API/Window/confirm)
    ```
    result = window.confirm(message);
    if (result) {
        ...
    }
    ```
* Events

## 其他
* [WindowOrWorkerGlobalScope](https://developer.mozilla.org/en-US/docs/Web/API/WindowOrWorkerGlobalScope)
    * [ ] caches
    * [ ] indexedDB
    * [ ] isSecureContext
    * [ ] origin
    * [ ] clearInterval: `scope.clearInterval(intervalID)`
    * [ ] clearTimeout
    * [ ] createImageBitmap()
    * [ ] fetch()
    * [setInterval](https://developer.mozilla.org/en-US/docs/Web/API/WindowOrWorkerGlobalScope/setInterval)
        ```javascript
        function happy() {
            console.log("");
        }
        var intervalID = window.setInterval(happy, 500)
        ```
    * [setTimeout](https://developer.mozilla.org/en-US/docs/Web/API/WindowOrWorkerGlobalScope/setTimeout)  
        setTimeout return an timeoutId(integer), it share the same id with setInterval. The clearTimeout() and clearInterval() can technicaly be used interchangebaly.
        * Syntax: `var timeoutId = scope.setTimeout(function, delay, param1, param2, ...)`
        * Example: `timeoutId = window.setTimeout(window.alert, 2000, 'That was relly slow!');`
* scroll滚动
    * 滚动到页面底部后更新  
    ```
        $(window).scroll(function() {
           if($(window).scrollTop() + $(window).height() +1 >= $(document).height()) {
               user_list_vm.show_more();
           }
        });
    ```

# 第三方包
## [Axios](https://github.com/axios/axios)
[异步await](./library/axios_await.js)
```
const axios = require('axios');
axios.get(
  '/user', {
    params: {
      staff: true
    }
  })
  .then(function(response) {
  })
axios.post('/user', data)
    .then(function(response) {
    })
    .catch(function(error) {
    })
```

## [eslint](https://eslint.org/)
格式化代码，我自己的规则
```
rules: {
  "indent": [
    "error", 2,  // 2缩进
    {
      "SwitchCase": 1  // switch内部也要缩进
    }
  ],
  "comma-dangle": ["error", "always-multiline"],  // 多行时最后要加逗号
  "no-debugger": "off",
  "no-unused-vars": "off",  // 开发时关闭，开发结束后打开
  "semi": "never",
}
```

## [get-fqdn](https://github.com/forwardemail/get-fqdn)
```
const getFQDN = require('get-fqdn');
const fqdn = await getFQDN()
console.log(fqdn)  // windows.ramwin.com
```

## [Lodash](./lodash.md)
一致性、模块化、高性能的 JavaScript 实用工具库。

## [Moment](https://momentjs.com/)
```
const moment = require("moment")
var m = moment(new Date())
m.format("YYYY-MM-DD")  // 生成的是m的时区的日期. 通过m.utcOffset(0)可以修改时区. 默认为当前时区
```
Parse, validate, manipulate, and display dates and times in JavaScript.
### [Document](https://momentjs.com/docs/)
* example
```
<script src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.22.2/moment-with-locales.min.js"></script>
<script>
  var now = moment(new Date())
  console.log(now.format("YYYY-MM-DD"))
  console.log(now.add(12, 'days').calendar());
  moment("20111031", "YYYYMMDD")
</script>
```
#### Get and Set time
```
let now = moment()
noe.hours(12).minutes(0).seconds(0)
```
* [manipulating](https://momentjs.com/docs/#/manipulating/)  
    It should be noted that moments are mutable. Calling any of the manipulation methods will **change** the original moment.
    * add: `moment().add(7, 'days|d|weeks|w|months|M|years|y')`
#### 计算时间
```
moment().add(7, 'days')
moment().subtract(7, 'days')
```
#### 展示时间
```
moment().format()  //  "2014-09-08T08:02:17-05:00"
moment().format("YYYY-MM-DD HH:mm:ss") 
```

#### durations
```
moment(moment.now() - moment.duration(2, 'hours'))
moment.substract(2, 'hours')  // 但是这样原来的时间就丢失了
```

## Papaparse
解析csv文件
```
import Papa from "papaparse"
Papa.parse(file|csvString|url, config: {}, complete: function(results) {})
```
* config
```
{
  header: true,
}
```

## [qs](https://www.npmjs.com/package/qs)
解析和格式化请求参数  
```
const qs = require('qs')
qs.parse('a=c') == { a: 'c'}
qs.stringify({a: [1,2,3]}, {indices: false}) == 'a=1&a=2&a=3'
```

# node
## [modules](https://nodejs.org/dist/latest-v14.x/docs/api/modules.html)
```
// animal.js
class Cat {
    constructor(name) {
        this.name = name
    }
    function say() {
        console.info(`miao: ${this.name}`)
    }
}
module.exports = {
    Cat
}
exports.Cat = Cat
exports.Cat = class Cat {...}
// run.js
const animal = require('./animal.js')
var cat =animal.Cat('kitty')
cat.say()
```
## vue的模块或者组件
```
Cat.vue
export default {
}
import Cat from "./Cat"
```

# [npm](https://docs.npmjs.com/)
```
npm config set registry https://registry.npm.taobao.org
npm config set registry https://registry.npmjs.org/
```
## [命令](https://docs.npmjs.com/cli-documentation/)
* [install](https://docs.npmjs.com/cli/v9/commands/npm-install)
```
npm install --save  // 以前的npm需要用save来自动修改package.json. 现在不需要这个参数了
npm install ramwin@latest // 升级
npm install -P|--save-prod  # 添加到dependencies
npm install -D|--save-dev  # 添加到devDependencies
npm install webpack@^5
npm uninstall <package>
```

* publish
```
npm publich  # 发布版本
```

* [shrinkwrap](https://docs.npmjs.com/cli/v6/commands/npm-shrinkwrap)
锁定版本

## npm-link-save
## [npm-link-better](https://github.com/laggingreflex/npm-link-better)
```
npm-link-better vue
```


[官网]: https://developer.mozilla.org/en-US/docs/Web/JavaScript
[对象基础文档]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Working_with_Objects
[Math]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Math
[Math.floor]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Math/floor
[expression]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators
[in]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/in
[逻辑操作]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Logical_Operators

[执行顺序]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Operator_Precedence
[localStorage]: https://developer.mozilla.org/en-US/docs/Web/API/Window/localStorage