ArkTS编程规范

// 类名
class User {
  username: string

  constructor(username: string) {
    this.username = username;
  }

  sayHi() {
    console.info('hi' + this.username);
  }
}

// 枚举名
enum UserType {
  TEACHER = 0,
  STUDENT = 1
};

// 命名空间
namespace Base64Utils {
  export function encrypt() {
    // todo encrypt
  }

  export function decrypt() {
    // todo decrypt
  }
};

let msg = 'Hello world';

function sendMsg(msg: string) {
  // todo send message
  // ...
}

let userName = 'Zhangsan';

function findUser(userName: string) {
  // todo find user by user name
  // ...
}

const MAX_USER_SIZE = 10000;

enum UserType1 {
  TEACHER = 0,
  STUDENT = 1
};

let isNoError = true;
let isNotFound = false;

function empty() {}
function next() {}

let isError = false;
let isFound = true;

function isEmpty() {}
function hasNext() {}

class DataSource {
  id: number = 0
  title: string = ''
  content: string = ''
}

const dataSource: DataSource[] = [
  {
    id: 1,
    title: 'Title 1',
    content: 'Content 1'
  },
  {
    id: 2,
    title: 'Title 2',
    content: 'Content 2'
  }

];

function test(dataSource: DataSource[]) {
  if (!dataSource.length) {
    return;
  }

  for (let data of dataSource) {
    if (!data || !data.id || !data.title || !data.content) {
      continue;
    }
    // some code
  }

  // some code
}

let condition = true;
if (condition)
  console.info('success');
for (let idx = 0; idx < 5; ++idx)
  console.info('', idx);

let condition = true;
if (condition) {
  console.info('success');
}
for (let idx = 0; idx < 5; ++idx) {
  console.info('', idx);
}

switch (condition) {
  case 0: {
    doSomething();
    break;
  }
  case 1: {
    doOtherthing();
    break;
  }
  default:
    break;
}

// 假设条件语句超出行宽
if (userCount > MAX_USER_COUNT ||
  userCount < MIN_USER_COUNT) {
  doSomething();
}

let maxCount = 10;
let isCompleted = false;
let pointX = 0;
let pointY = 0;

  // if 和左括号 ( 之间没有加空格
  if(isJedi) {
    fight();
  }
  // ...
// 函数名fight和左括号 ( 之间加了空格
function fightBad (): void {
  console.info('Swooosh!');
}

  // if 和左括号之间加一个空格
  if (isJedi) {
    fight();
  }
  // ...
// 函数名fight和左括号 ( 之间不加空格
function fight(): void {
  console.info('Swooosh!');
}

if (flag) {
  // ...
}else { // else 与其前面的大括号 } 之间没有加空格
  // ...
}

if (flag) {
  // ...
} else { // else 与其前面的大括号 } 之间增加空格
  // ...
}

function foo() { // 函数声明时，左大括号 { 之前加个空格
  // ...
}

bar('attr', { // 左大括号前加个空格
  age: '1 year',
  sbreed: 'Bernese Mountain Dog',
});

const arr = [1, 2, 3]; // 数组初始化中的逗号后面加个空格，逗号前面不加空格
myFunc(bar1, foo1, baz); // 函数的多个参数之间的逗号后加个空格，逗号前面不加空格

let message1 = "world";
console.info(message1);

let message2 = 'world';
console.info(message2);

interface I {
  name: string
  age: number
  value: number
  sum: number
  foo: boolean
  bar: boolean
}

let obj1: I = { name: 'tom', age: 16, value: 1, sum: 2, foo: true, bar: false }

interface I {
  name: string
  age: number
  value: number
  sum: number
  foo: boolean
  bar: boolean
}

// ...
let obj2: I = {
  name: 'tom',
  age: 16,
  value: 1,
  sum: 2,
  foo: true,
  bar: false
}

if (isOk) {
  doThing1();
  doThing2();
}
else {
  doThing3();
}

if (isOk) {
  doThing1();
  doThing2();
} else {
  doThing3();
}

try {
  doSomething();
}
catch (err) {
  // 处理错误
}

try {
  doSomething();
} catch (err) {
  // 处理错误
}

function foo1()
{
  // ...
}

function foo2() {
  // ...
}

class C1 {
  count: number = 0

  getCount(): number {
    return this.count
  }
}

class C2 {
  private count: number = 0

  public getCount(): number {
    return this.count
  }
}

const num1 = .5;
const num2 = 2.;
const num3 = -.7;

const num4 = 0.5;
const num5 = 2.0;
const num6 = -0.7;

if (foo == Number.NaN) {
  // ...
}

if (foo != Number.NaN) {
  // ...
}

if (Number.isNaN(foo)) {
  // ...
}

if (!Number.isNaN(foo)) {
  // ...
}

const numbers = [1, 2, 3, 4, 5];
// 依赖已有数组来创建新的数组时，通过for遍历，生成一个新数组
const increasedByOne1: number[] = [];
for (let i = 0; i < numbers.length; i++) {
  increasedByOne1.push(numbers[i] + 1);
}

const numbers = [1, 2, 3, 4, 5];
// ...
// better: 使用map方法是更好的方式
const increasedByOne2: number[] = numbers.map(num => num + 1);

// 在控制性判断中赋值不易理解
if (isFoo = false) {
  // ...
}

const isFoo = false; // 在上面赋值，if条件判断中直接使用
if (isFoo) {
  // ...
}

function foo4() {
  try {
    // ...
    return 1;
  } catch (err) {
    // ...
    return 2;
  } finally {
    return 3;
  }
}

function foo5() {
  try {
    // ...
    return 1;
  } catch (err) {
    // ...
    return 2;
  } finally {
    console.info('XXX!');
  }
}

// lib.ets
export interface I {
  sum: number
}

export function getObject1(value: number): I {
  let obj: I = { sum: value };
  return obj
}

// Index.ets
import { getObject1 } from './lib';
// ...
let obj1: ESObject = getObject1(123);

// lib.ets
export interface I {
  sum: number
}

// ...
export function getObject2(value: number): I {
  let obj: I = { sum: value };
  return obj
}

// Index.ets
import { getObject2, I } from './lib';
// ...
let obj2: I = getObject2(123);

let x: Array<number> = [1, 2, 3];
let y: Array<string> = ['a', 'b', 'c'];

// 统一使用T[]语法
let x: number[] = [1, 2, 3];
let y: string[] = ['a', 'b', 'c'];