如何進修一門言語

是什麼? 與es的關聯?

以面向對象的頭腦編程?

代碼花樣的流轉?

我們在做什麼?

// C-D 強數據操縱
import { observable, action } from 'mobx'

export default class StoreBase {
  service: any

  @observable state = ''
  @observable list = []
  @observable loading = false
  @observable totalCount = 0
  @observable counter = 0
  @observable pageSize = 10
  @observable pageIndex = 1
  @observable submiting = false
  @observable initialFormValue = {}

  constructor(service) {
    this.service = service
  }

  @action changeSize(pageSize) {
    this.pageSize = pageSize
  }

  @action async getPageList(options: { pageIndex?: number, pageSize?: number }) {
    options.pageIndex = options.pageIndex || this.pageIndex
    options.pageSize = options.pageSize || this.pageSize
    this.pageIndex = options.pageIndex
    this.pageSize = options.pageSize
    this.loading = true
    const result = await this.service.list(options)
    this.loading = false
    this.list = result.data
    this.totalCount = result.totalCount
  }

  @action async add(body) {
    this.submiting = true
    try {
      const result = await this.service.add(body)
      if (result.statusCode && result.statusCode !== 200) {
        throw new Error(result.message)
      }
    } catch (error) {
      throw error
    } finally {
      this.submiting = false
    }
  }

  @action async edit(id, body) {
    this.submiting = true
    try {
      const result = await this.service.update(id, body)
      if (result.statusCode && result.statusCode !== 200) {
        throw new Error(result.message)
      }
    } catch (error) {
      throw error
    } finally {
      this.submiting = false
    }
  }

  @action async remove(id) {
    try {
      await this.service.delete(id)
      this.getPageList({ pageIndex: this.pageIndex })
    } catch (error) {
      throw error
    }
  }

  @action initializeForm(form) {
    this.initialFormValue = form
  }
}

我們做的web application是由組件集組裝起來的, application的質量取決於 組件的質量
什麼是組件的質量? 如何寫出質量好的組件?

ts 有什麼? 是如何使得我們能產出高質量組件

範例體系 之 原子範例

// boolean
let judge: boolean = true;

// string
let girl: string = `${family.join('======')}`;

// any
const think: any = {}
think = [];
think = '';
think = 1037;

// void
function select(): void { 
    return null;
}

// never
function logger(message: string): never { 
    throw new Error(message);
}

範例體系 之 組合範例

// 數組範例
let family: string[] = ["epuisite", "love", "detail"];
let team: Array<number> = [1, 3, 7];
interface teamArray { 
    [index: number]: any
}
let t: teamArray = [1, 2, 3, {1: 3}];
// 元組
let structure: [string, Array<string>];
structure = ['why', ['atomic element', 'what']];
structure[2] = 'how';
structure[3] = ['when'];

// function範例
interface Doing { 
    (type: number, thing: string, when?: string|number): any[]
}

let mydoing: Doing;
function f(type: number = 2, thing?: string, when?: string|number, ...items: any[]) { 
    return type;
}

function sf(message: number): number;
function sf(message: string): string;
function sf(message: number | string): number | string { 
    if (message as number) {
        return 1;
    } else { 
        return '123';
    }
}

// 羅列範例  数字範例的值
const Color = {Red, Green, Blue};
enum Direction{  
    Up=1,  
    Down,  
    Left,  
    Right  
}  

// 自定義範例
// 對象範例 - 接口
interface Mother { 
    readonly id: number,
    detail: any[],
    learning: string,
    love: boolean,
    housework?: boolean,
    [proName: string]: any
}
let me: Mother = {
    id: new Date().getTime(),
    detail: ['water', 137, 'cloud', 'grass', 'nose'],
    learning: 'a wider world',
    love: true,
    doing() { 
        return 137;
    }
};

東西 是什麼? 怎樣用? 為什麼用?

泛型

function createArray<T>(length: number, value: T): Array<T> { 
    let result: T[] = [];
    for (let i = 0; i < length; i++) { 
        result[i] = value;
    }
    return result;
}

function swap<T = number, U = number>(tuple: [T, U]): [U, T] { 
    return [tuple[1], tuple[0]];
}


interface lengthwish { 
    length: number
}

function swap2<T extends lengthwish, U>(tuple: [T, U]): [U, T] { 
    return [tuple[1], tuple[0]];
}

interface createArrayFunc { 
    <T extends lengthwish>(length: number, value: T): Array<T>;
}

let myCreateArray: createArrayFunc;
myCreateArray = function <T extends lengthwish>(length: number, value: T): Array[T] { 
    let result: T[] = [];
    for (let i = 0; i < length; i++) { 
        result[i] = value;
    }

    return result;
}

// 團結範例[共有的屬性和要領 + 範例推論]
let cooperation: string | number | boolean | null | undefined;
cooperation = 1;
cooperation = null;



// 範例斷言
function determine(config: number[] | string ): boolean {
    if ((<string>config).length || (<number[]>config).length) {
        return true;
    } else { 
        return false
    }
 }

type Name = string;
type DoFn = () => string;
type cof = Name | Dofn;
function o(message: cof): Name { 
    return '';
}