Question

我想在基于打字稿的项目中在自己的文件中定义几个接口，我将从中实现用于生产的类以及用于测试的模拟。但是，我无法弄清楚正确的语法是什么。我已经找到了很多关于声明接口和实现它们的教程，但是它们在同一个文件中都有一个简单的接口和派生类的实现，这不是非常真实的。导出和导入接口的正确方法是什么？

Answer 1

You need to export the interface from the file in which is defined and import it wherever you want to use it.

in IfcSampleInterface.ts:

export interface IfcSampleInterface {
   key: string;
   value: string;
}

In SampleInterface.ts

import { IfcSampleInterface } from './IfcSampleInterface';
let sampleVar: IfcSampleInterface;

Answer 2

使用定义（d.ts）文件和命名空间，无需以这种方式导入/导出模块。 DefinitelyTyped项目有guidance和大量examples如何做。

Answer 3

仅导出一些接口

在不传播多个导出的情况下，您可以将它们分为一个public class MainActivity extends AppCompatActivity { public static final String SHARED_PREF="SHARED_PREFS"; public static final String KEY="KEY_TEXT"; private EditText editText; private Button button; private Button button2; private TextView final_text; private TextView editText3; private int val_two; private String food_list; private String id; private NotificationChannel channel; @Override protected void onCreate(Bundle savedInstanceState) { if(Build.VERSION.SDK_INT>= Build.VERSION_CODES.O){ channel = new NotificationChannel(NotificationChannel.DEFAULT_CHANNEL_ID, "notifChan2", NotificationManager.IMPORTANCE_HIGH); channel.setDescription("A calorie notification"); } button.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { String val = editText.getText().toString(); String food = editText3.getText().toString(); food_list.concat(food); val_two = val_two + Integer.parseInt(val); SharedPreferences sharedPreferences = getSharedPreferences(SHARED_PREF,0); SharedPreferences.Editor editor = sharedPreferences.edit(); editor.putInt(KEY, val_two); editor.apply(); String finalText = "You current calories " + val_two ; if(val_two>1000){ DisplayNotification(); } final_text.setText(finalText); callupdatewidget() function this will print the current calories into the wdiget callUpdateWidget(MainActivity.this,finalText); } }); } private void DisplayNotification() { NotificationCompat.Builder notify = new NotificationCompat.Builder(this, NotificationChannel.DEFAULT_CHANNEL_ID) .setSmallIcon(android.R.drawable.ic_menu_agenda) .setContentTitle("Congrats!") .setContentText("You have reached your calorie goal of 1000!"); NotificationManagerCompat notificationMgr = NotificationManagerCompat.from((this)); notificationMgr.notify(1, notify.build()); } }块（在这种情况下，没有文件export {} 类型应为声明）：

default

导入示例

// interfaces.ts
interface IWords {
  [key: string]: string; 
}

interface INumbers {
  [key: string]: number; 
}

interface IBooleans {
  [key: string]: boolean; 
}

interface IValues {
  [key: string]: string | number; 
}

interface IStructures {
  [key: string]: INumbers | IBooleans | IValues;
}

export {
  // not exporting IWords | INumbers
  IBooleans,
  IValues,
  IStructures,
}

Answer 4

您需要导出已定义的文件中的接口，并将其导入到所使用的文件中。有关示例，请参阅此链接。

x.ts

interface X{
    ...
}
export default X

y.ts

import X from "./x.ts"
// You can use X now

有关详细信息，请参阅https://www.typescriptlang.org/docs/handbook/modules.html

Answer 5

您可以在相对较新的项目中使用以下语法

`import type { xxx } from './xxx'`

https://www.typescriptlang.org/docs/handbook/release-notes/typescript-3-8.html

如何在单独的文件中声明和导入typescript接口

5 个答案:

仅导出一些接口

导入示例