TypeScript笔记(持续更新）
一、TS安装
npm i typescript -g
直接安装
二、基本使用
1.创建TS文件
2.编写TS代码
3.终端输入
tsc 文件名.ts
进行编译成js文件
三、基本配置
终端输入
tsc --init
创建tsconfig.json配置文件
files:[] //要编译的文件，设置之后就直接终端输入tsc即可编译
outDir // 编译输出到目标文件夹下，整合编译之后的文件
noEmitOnError: true, //代码出错的时候不进行编译
自动编译：配置好后点击终端–》运行任务–》tsc监视 即可自动编译
{
"compilerOptions": {
/* Basic Options */
// "incremental": true, /* Enable incremental compilation */
"target": "es5", /* Specify ECMAScript target version: 'ES3' (default), 'ES5', 'ES2015', 'ES2016', 'ES2017', 'ES2018', 'ES2019' or 'ESNEXT'. */
"module": "commonjs", /* Specify module code generation: 'none', 'commonjs', 'amd', 'system', 'umd', 'es2015', or 'ESNext'. */
// "lib": [], /* Specify library files to be included in the compilation. */
// "allowJs": true, /* Allow javascript files to be compiled. */
// "checkJs": true, /* Report errors in .js files. */
// "jsx": "preserve", /* Specify JSX code generation: 'preserve', 'react-native', or 'react'. */
// "declaration": true, /* Generates corresponding '.d.ts' file. */
// "declarationMap": true, /* Generates a sourcemap for each corresponding '.d.ts' file. */
// "sourceMap": true, /* Generates corresponding '.map' file. */
// "outFile": "./", /* Concatenate and emit output to single file. */
"outDir": "./dist", /*编译输出到目标文件夹下*/
// "rootDir": "./", /* Specify the root directory of input files. Use to control the output directory structure with --outDir. */
// "composite": true, /* Enable project compilation */
// "tsBuildInfoFile": "./", /* Specify file to store incremental compilation information */
// "removeComments": true, /* Do not emit comments to output. */
// "noEmit": true, /* Do not emit outputs. */
// "importHelpers": true, /* Import emit helpers from 'tslib'. */
// "downlevelIteration": true, /* Provide full support for iterables in 'for-of', spread, and destructuring when targeting 'ES5' or 'ES3'. */
// "isolatedModules": true, /* Transpile each file as a separate module (similar to 'ts.transpileModule'). */
/* Strict Type-Checking Options */
"strict": true, /* Enable all strict type-checking options. */
// "noImplicitAny": true, /* Raise error on expressions and declarations with an implied 'any' type. */
// "strictNullChecks": true, /* Enable strict null checks. */
// "strictFunctionTypes": true, /* Enable strict checking of function types. */
// "strictBindCallApply": true, /* Enable strict 'bind', 'call', and 'apply' methods on functions. */
// "strictPropertyInitialization": true, /* Enable strict checking of property initialization in classes. */
// "noImplicitThis": true, /* Raise error on 'this' expressions with an implied 'any' type. */
// "alwaysStrict": true, /* Parse in strict mode and emit "use strict" for each source file. */
/* Additional Checks */
// "noUnusedLocals": true, /* Report errors on unused locals. */
// "noUnusedParameters": true, /* Report errors on unused parameters. */
// "noImplicitReturns": true, /* Report error when not all code paths in function return a value. */
// "noFallthroughCasesInSwitch": true, /* Report errors for fallthrough cases in switch statement. */
/* Module Resolution Options */
// "moduleResolution": "node", /* Specify module resolution strategy: 'node' (Node.js) or 'classic' (TypeScript pre-1.6). */
// "baseUrl": "./", /* Base directory to resolve non-absolute module names. */
// "paths": {}, /* A series of entries which re-map imports to lookup locations relative to the 'baseUrl'. */
// "rootDirs": [], /* List of root folders whose combined content represents the structure of the project at runtime. */
// "typeRoots": [], /* List of folders to include type definitions from. */
// "types": [], /* Type declaration files to be included in compilation. */
// "allowSyntheticDefaultImports": true, /* Allow default imports from modules with no default export. This does not affect code emit, just typechecking. */
"esModuleInterop": true, /* Enables emit interoperability between CommonJS and ES Modules via creation of namespace objects for all imports. Implies 'allowSyntheticDefaultImports'. */
// "preserveSymlinks": true, /* Do not resolve the real path of symlinks. */
// "allowUmdGlobalAccess": true, /* Allow accessing UMD globals from modules. */
/* Source Map Options */
// "sourceRoot": "", /* Specify the location where debugger should locate TypeScript files instead of source locations. */
// "mapRoot": "", /* Specify the location where debugger should locate map files instead of generated locations. */
// "inlineSourceMap": true, /* Emit a single file with source maps instead of having a separate file. */
// "inlineSources": true, /* Emit the source alongside the sourcemaps within a single file; requires '--inlineSourceMap' or '--sourceMap' to be set. */
/* Experimental Options */
// "experimentalDecorators": true, /* Enables experimental support for ES7 decorators. */
// "emitDecoratorMetadata": true, /* Enables experimental support for emitting type metadata for decorators. */
/* Advanced Options */
"forceConsistentCasingInFileNames": true /* Disallow inconsistently-cased references to the same file. */
},
"files": [ //编译文件
"greeter.ts"
]
}
四、TS的数据类型
let username:string = "zlj"; //字符串类型
let userage:number = 17; //数字类型
let isshuai:boolean = true; //布尔类型
let arrObj = {
"name":"小明",
"age":18
} //对象类型
let arrStudent = ["123","456","789"] //数组类型
let arrNum:number[] = [12,5,8] //显示声明数组类型
let arrStr:string[] = ["sadasd","daada","qwerdq"]
let MixArr:(number|string)[] = ["asdada",12312] //混合声明
enum direction { //enum 枚举类型，能够自动向下枚举
one = 1,
two,
three,
four
}
function play(dir:direction){ //声明参数dir为定义好的枚举类型
if(dir === 1){
console.log("第一");
}else{
console.log(dir);
}
}
play(1)
function showAge(age:number):number{ //ts不仅可以规定参数的类型，还可以规定返回值的类型
return age
}
console.log(showAge(18))
五、TS的类
class Person{ //用class关键字声明一个类
name:string;
age:number;
private money:number = 10000000; //private为私有修饰符，不写的话默认是public
constructor(name:string,age:number){ //constructor是构造器
this.name = name,
this.age = age
}
favoriteFood(food:string){
console.log(food)
}
showMoney(){
return this.money //私有属性只能在类本身里访问，在外部无法访问
}
getMonry(salary:number):number{
return this.money+= salary
}
}
let zlj = new Person("王二麻子",18) //使用new关键字对之前声明的类进行实例化
zlj.favoriteFood("麻婆豆腐")
console.log(zlj.showMoney())
console.log(zlj.getMonry(666))
六、类的继承
super在子类的constructor中调用，是在子类中执行了父类的构造函数，其实是无关父类原型的，如果想到改变父类的原型方法，可以直接重名覆盖，如果想利用父类原型方法，也可以用super.method来引用。
如果你不在constructor里写super并传入相应参数，那么相当于只继承原型方法。
每个类自己的constructor其实就是定义自身的属性和方法，而不是原型上的。可以直接使用this.abc来添加，this指自己，super指父类。
子类继承的时候不写constructor，则默认会把父类自身的属性和方法生成到子类。
class Person{ //用class关键字声明一个类
name:string;
age:number;
private money:number = 10000000; //private为私有修饰符，不写的话默认是public
constructor(name:string,age:number){ //constructor是构造器
this.name = name,
this.age = age
}
favoriteFood(food:string){
console.log(food)
}
showMoney(){
return this.money //私有属性只能在类本身里访问，在外部无法访问
}
getMonry(salary:number):number{
return this.money+= salary
}
}
class son extends Person{ //用entends关键字来继承
constructor(name:string,age:number) {
super(name,age) //用super()来继承数据
}
}
let mySon = new son("李狗蛋",5)
console.log(mySon.showMoney()) //在子类里调用被继承类中的方法
七、抽象类的概念
抽象类只能被继承，不能被实例化
abstract class Jigoubiaozhun{ //用anstracr关键字标识为抽象类
abstract jigouName:string; //用abstract标识必须的属性
abstract showMoney():number; //用abstract标识必须的属性，同时规定好参数和返回值的类型
age:number = 50; //没有abstract就代表不是必须属性
}
//抽象类的作用一般是作为构建类时的一些标准去使用，通过继承这些标准，来规定这些类必须要有什么属性以及方法
//抽象类的子类必须实现抽象类的抽象方法
class Xinjiangjigou extends Jigoubiaozhun{
jigouName:string = "新疆挖井队"; //必须有这个抽象类中的属性
money:number = 50000000;
showMoney():number{ //必须有这个抽象类中的方法
return this.money
}
constructor(){
super() //调用super()
}
}
let Myjigou = new Xinjiangjigou()
console.log(Myjigou.showMoney())
八、接口
interface data{
name:string,
age:number
}
//通过关键字interface定义一个接口
//接口类似于一个规范，当数据的类型为该接口时，数据的接口需要和接口完全一致
function person(girl:data ){ //这里的girl使用了接口，那么它能就收到的数据就只有接口中定义的name和age，还有一个hobbits是接受不到的
console.log(girl.name)
console.log(girl.age)
// console.log(girl.hobbit) //这里打印hobbits会报错
}
const xiaohong= { //如果这里使用了接口，那么能够定义的属性也只有name和age了，再加其他属性会报错
name:"xiaohong",
age:18,
hobbit:"做面包"
}
person(xiaohong)