2017年12月1日 (五) 07:54的版本

QuickStart

0、安装npm。
 
1、新建项目文件夹angular2，放入4个初始文件。
    package.jon
    tsconfig.json
    typings.json
    systemjs.config.js
 
2、安装包，项目文件夹下就会新增node_modules、typings文件夹。
    npm install
 
3、在项目文件夹根下运用文件夹app，新增3个运用文件。
    app.component.ts
    app.module.ts
    main.ts
 
4、在项目文件夹下新增2个文件。
    index.html
    types.css
 
5、编辑、运行程序。使用Browsersync来动态刷新页面。
    npm start

安装ng2-file-upload

在项目目录下，运行如下命令：

npm install ng2-file-upload --save

Tutorial

The Hero Editor

Let’s take stock of what we’ve built.

• Our Tour of Heroes uses the double curly braces of interpolation (a kind of one-way data binding) to display the application title and properties of a Hero object.
• We wrote a multi-line template using ES2015’s template strings to make our template readable.
• We can both display and change the hero’s name after adding a two-way data binding to the <input> element using the built-in ngModel directive.
• The ngModel directive also propagates changes to every other binding of the hero.name.

Master/Detail

Here’s what we achieved in this chapter:

• Our Tour of Heroes now displays a list of selectable heroes
• We added the ability to select a hero and show the hero’s details
• We learned how to use the built-in directives ngIf and ngFor in a component’s template

Multiple Components

Let’s take stock of what we’ve built.

• We created a reusable component
• We learned how to make a component accept input
• We learned to declare the application directives we need in an Angular module. We list the directives in the NgModule * decorator's declarations array.
• We learned to bind a parent component to a child component.

Services

Let’s take stock of what we’ve built.

• We created a service class that can be shared by many components.
• We used the ngOnInit Lifecycle Hook to get our heroes when our AppComponent activates.
• We defined our HeroService as a provider for our AppComponent.
• We created mock hero data and imported them into our service.
• We designed our service to return a Promise and our component to get our data from the Promise.

ng lint规则

• Shadowed variable: 'res'
• 注释要以空格开头
• 双引号全用单引号代替
• 组件selector要以“app-”开头
• 文件要以空行结尾
• 不能省略代码块最后一行的分号
• 变量要以let声明
• 变量值未改变的量要用const声明
• 有初始值的变量不用写类型声明

代码片段

file-size.pipe.ts

import {Pipe, PipeTransform} from '@angular/core';
 
/*
 * Convert bytes into largest possible unit.
 * Takes an precision argument that defaults to 2.
 * Usage:
 *   bytes | humanFileSize:precision
 * Example:
 *   {{ 1024 |  humanFileSize}}
 *   formats to: 1 KB
*/
@Pipe({
    name: 'fileSize'
})
export class FileSizePipe implements PipeTransform {
    // In fact unit we should be get from Static Api, at the moment we set static
    private units = ['B', 'KB', 'MB', 'GB', 'TB', 'PB', 'EB', 'ZB', 'YB'];
    // In French
    // private units = ['bit', 'kilo', 'Mo', 'Go', 'To', 'bps', 'dpi'];
    public transform(bytes: number = 0, precision: number = 2): string {
        if (isNaN(parseFloat(String(bytes))) || !isFinite(bytes)) {
            return bytes.toString();
        }
        let unit = 0;
        while (bytes >= 1024) {
            bytes /= 1024;
            unit++;
        }
 
        return bytes.toFixed(precision).toString().replace(/\./g, ',') + ' ' + this.units[unit];
    }
}

二维码

npm install angularx-qrcode --save