打字稿的不同导入和导出形式

Question

我是打字新手。任何人都可以向我解释这些出口之间的区别：

export default class Foo {}
/* or */
class Foo {}
export = Foo;
/* or */
export class Foo { }

以及这几种导入形式的区别：

import x = require('y');
import x from 'y';
import { x } from 'y'
import * as x from 'y';

什么时候使用它们？

Answer 1

都在modules docs page:

Default exports

export default class Foo {}
// and
import x from 'y';

Each module can optionally export a default export. Default exports are marked with the keyword default; and there can only be one default export per module. default exports are imported using a different import form.

Export =

export = Foo;
// and
import x = require('y');

Both CommonJS and AMD generally have the concept of an exports object which contains all exports from a module.

They also support replacing the exports object with a custom single object. Default exports are meant to act as a replacement for this behavior; however, the two are incompatible. TypeScript supports export = to model the traditional CommonJS and AMD workflow.

The export = syntax specifies a single object that is exported from the module. This can be a class, interface, namespace, function, or enum.

When importing a module using export =, TypeScript-specific import let = require("module") must be used to import the module.

您包含的其他表格：

export class Foo { }
// and
import { x } from 'y'
import * as x from 'y';

是export and import的正常形式。
它基于 es6 import/export 语法，您也可以在 MDN 中找到更多信息：import / export.

打字稿的不同导入和导出形式

different import and export form of typescript

typescript

typescript2.0