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最近笔者在学习typescript对于配置上问题基本做一个小小的笔记总结下：
1.创建项目：
- 新建文件夹
typescript,创建后，执行tsc --init命令 - 执行后，文件夹中会多出一个名为
tscconfig.json的文件，这个文件就是对typescript文件编译的配置文件，内容如下：
{
"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": "./", /* Redirect output structure to the directory. */
// "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. */
}
}
2.配置文件浅析：
1.tscconfig.json生效问题：
在typescript文件夹下新建一个demo.ts文件，这个文件用测试tscconfig.json配置文件的效果：
//注释:demo.ts
const player:string = "我一直都想证明:努力是能够超越天才的!";
配置文件中"removeComments": true意思是编译后删除ts文件中的注释，命令行中运行tsc demo.ts发现，编译后的文件并没有删除注释:demo.ts文件，这就说明了:
- 通过
tsc demo.ts执行后，tscconfig.json并没有发生作用 - 直接运行
tsc，tsconfig.json发生作用
2.在一个或者多个文件中使用tscconfig.json配置进行编译：
tsc命令默认会让文件夹中所有的ts文件都通过tscconfig.json的配置进行编译：
tsconfig.ts中添加"include": ["./demo.ts"]，执行tsc后，及时文件中有多个ts文件,只编译demo.ts文件files:["./demo.ts"]作用和include相似- 与
include相对应的，还有一个exclude，意思是编译所有的内容除了，
{
"include": ["./demo.ts"],
"compilerOptions": {
/* Basic Options */
// "incremental": true, /* Enable incremental compilation */
//...省略🤭
"target": "es5", /* Specify ECMAScript target version: 'ES3' (default), 'ES5', 'ES2015', 'ES2016', 'ES2017', 'ES2018', 'ES2019' or 'ESNEXT'. */
"module": "commonjs", /* Specify module code generation: 'none',
}
}
通过ts-node + ts文件名也会通过tscconfig.js文件进行配置。
3.指定编译文件夹和输出文件夹：
-
"outDir": "./build":指定编译后的文件在build文件夹中 -
"rotDir": "./src":指定需要编译的文件夹文件
4.增量编译："incremental": true
顾名思义，就是之前编译过的内容不做编译，只对新增的内容进行编译，开启后执行tsc命令后，文件夹中会多出一个tsconfig.tsbuildinfo的文件，其中存储着上次编译的信息，再次编译的时候，它会进行通过这些信息进行比对，已经编译过的就不编译了。
以上算是对一些常用的简单介绍，更多的还是需要去官网进行尝试。
