add typescript

2017:09/03.md

+# TypeScript
+
+## varibale
+
+```js
+
+// boolean
+let createdByNewBoolean: Boolean = new Boolean(1);
+let createdByBoolean: boolean = Boolean(1);
+
+// number
+let decLiteral: number = 6;
+let octalLiteral: number = 0o744;   // 八进制
+var notANumber = NaN;
+
+// string
+let myName: string = 'test'
+
+// undefined and null
+let u: undefined = undefined;
+let n: null = null;
+let num: number = undefined;    // 为其他类型的子类型
+
+// any 允许被赋值为任何类型， default
+let myFavoriteNumber: any = 'seven';
+myFavoriteNumber = 7;
+
+// union types
+let myFavoriteNumber: string | number;
+
+
+```
+
+## interfaces
+
+```js
+interface Person {
+  readonly id: number;      // 只能在创建的时候被赋值，不能再改了
+  name: string;
+  age?: number;   // ？ 可选属性
+  [propName: string]: any;   // 任意属性，（确定属性及可选属性需为其子属性）
+}
+
+let gy: Person {
+  name: 'gy',
+  age?: 23,
+}
+
+```
+
+## array
+
+```js
+let fibonacci: number[] = [1, 1, 3];
+let strnacci: string[] = ['1', '2', '3'];
+
+// Generic 范型
+let fib: Array<number> = [1, 2, 3, 4, 5];
+
+// use Interface
+interface  NumberArr {
+  [index: number]: number
+}
+let test: NumberArr = [1, 2, 3, 4, 5];
+
+// 任意类型
+let list: any[] = ['test', 1];
+```
+
+## function
+
+```js
+// function declaration
+function sum(x: number, y:number): number {
+  return x + y;
+}
+
+// function expression
+var sum: (x: number, y: number) => number = function(x: number, y: number): number {
+  return x + y;
+}
+
+// or use interface
+interface SearchFuc {
+  (source: string, subString: string): boolean;
+}
+
+let search: SearchFuc;
+search = function(source: string, subString: string) {
+  return source.search(subString) !== -1;
+}
+
+// 可选参数
+function sum(a: number, b: number, c?: number) {
+  if (c) {
+    return a + b + c;
+  }
+  return a + b;
+}
+```
+
+## assert
+
+```js
+// 类型断言
+<类型>值
+值 as 类型
+```
+
+## 声明文件
+
+```js
+// 当使用第三方库时，我们需要引用它的声明文件，通常将其所有声明文件放入单独的文件中
+
+// jQuery.d.ts
+declare var jQuery: (string) => any;
+
+// 在使用的文件中，使用三「三斜线」 表明引用的声明文件
+/// <reference path='./jQuery.d.ts'></reference>
+
+// 使用工具
+@types
+npm install @types/jquery --save-dev
+
+```
+
+## 内置对象
+
+```js
+// Boolean, Error, Date, RegExp
+let b: Boolean = new Boolean(1);
+let e: Error = new Error('Error occurred');
+let d: Date = new Date();
+let r: RegExp = /[a-z]/;
+
+
+// DOM and BOM
+Document, HTMLElement, Event, NodeList
+let body: HTMLElement = document.body;
+let allDiv: NodeList = document.querySelectorAll('div');
+document.addEventListener('click',function(e: MouseEvent)) {
+  // do sth
+}
+```
+
+## 类型别名
+
+```js
+type Name = string;
+type NameResolver = () => string;
+type NameOrResolver = Name | NameResolver;
+function getName(n: NameOrResolver): Name {
+  if (typeof n === 'string') {
+    return n
+  } else {
+    return n();
+  }
+}
+
+```
+
+## 字符串字面量类型
+
+```js
+type EventNames = 'click' | 'scroll' | 'mousemover';
+function handleEvent(ele: Element, event: EventNames) {
+  // do sth
+}
+
+handleEvent(ele, 'scroll');
+handleEvent(ele, 'click');
+```
+
+## enum
+
+```js
+enum Days {a, b, c, d, e, f, g};
+
+```
+
+## 泛型
+
+```js
+function createArray<T>(length: number, value: T): Array<T> {
+  let result = [];
+  for (let i = 0; i < length; i++) {
+    result[i] = value;
+  }
+  return result;
+}
+
+createArray<string>(3, 'x'); // ['x', 'x', 'x']
+
+```
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test.js

+var gy = {
+    name: 'gy',
+    age: 12
+};

test.ts

+interface Person {
+  name: string;
+  age: number;
+}
+
+let gy: Person = {
+  name: 'gy',
+  age: 12,
+}
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