Typescript环境配置 (vscode)

typescript环境配置

安装node, 安装cnpm

安装typescript, ts-node

cnpm install -g typescript
cnpm install -g ts-node

用vscode打开项目文件夹

tsc -init 生成一个tsconfig.json文件
文件如下：

{
  "compilerOptions": {
    /* Visit https://aka.ms/tsconfig.json to read more about this file */

    /* Basic Options */
    // "incremental": true,                         /* Enable incremental compilation */
    "target": "ES2015",                                /* Specify ECMAScript target version: 'ES3' (default), 'ES5', 'ES2015', 'ES2016', 'ES2017', 'ES2018', 'ES2019', 'ES2020', 'ES2021', or 'ESNEXT'. */
    "module": "ES2015",                           /* Specify module code generation: 'none', 'commonjs', 'amd', 'system', 'umd', 'es2015', 'es2020', 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', 'react', 'react-jsx' or 'react-jsxdev'. */
    // "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",                              /* Redirect output structure to the directory. */
     "rootDir": "./src",                             /* 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. */
    // "noUncheckedIndexedAccess": true,            /* Include 'undefined' in index signature results */
    // "noImplicitOverride": true,                  /* Ensure overriding members in derived classes are marked with an 'override' modifier. */
    // "noPropertyAccessFromIndexSignature": true,  /* Require undeclared properties from index signatures to use element accesses. */

    /* 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 */
    "skipLibCheck": true,                           /* Skip type checking of declaration files. */
    "forceConsistentCasingInFileNames": true        /* Disallow inconsistently-cased references to the same file. */
  },
  "include": [
        "src/**/*"
    ],
    "exclude": [
        "node_modules",
        "**/*.spec.ts"
    ]
}

不带任何输入文件的情况下调用tsc，编译器会从当前目录开始去查找tsconfig.json文件，逐级向上搜索父目录。
因此我们通过tsc命令直接就可以运行src目录下的所有ts文件
修改输出文件所在目录： "outDir":"./dist"

npm init -y生成package.json文件 -y表示一路yes

修改package.json文件，如下：

{
  "name": "hello-typescript",
  "version": "0.0.1",
  "description": "Learning TypeScript.",
  "scripts": {
    "start": "concurrently "npm run tsc:w" "npm run lite"",
    "lite": "lite-server",
    "tsc": "tsc",
    "tsc:w": "tsc -w"
  },
  "author": "raiuny",
  "license": "ISC",
  "dependencies": {
    "@types/node": "^16.7.1"
  },
  "devDependencies": {
    "concurrently": "^6.2.1",
    "lite-server": "^2.6.1"
  },
  "main": "app.js",
  "keywords": []
}

此属性定义了当我们引用依赖时的文件地址。
不使用main属性的话我们可能需要这样写引用：require("some-module/dist/app.js")，如果我们在main属性中指定了dist/app.js的话，我们就可以直接引用依赖就可以了：require("some-module")

安装相关依赖

cnpm install

新建一个index.html文件

<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <title>HelloTypeScript</title>
</head>

<body>
    <h2>Hello TypeScript</h2>
</body>
<script src="./dist/test.js"></script>
<!-- 这里引入编译后生成的js文件 -->

</html>

新建src目录下的需要编译的ts文件

src/test.ts

function sayHello(person: string) {
    return "hello " + person;
  }
  
console.log("object :", sayHello("Typescript"));

运行

npm run start

执行后可以访问localhost:3000，展示的页面就是index.html，按下F12可以看到console上输出的结果。

PS: vscode上使用Code Run插件也可以直接运行ts文件，需要先安装ts-node

cnpm install ts-node -g