Angular2关于定义一些全局常量，以及在页面中引用

//SettingsService 

import { Injectable } from '@angular/core';
declare var $: any;

@Injectable()
export class SettingsService {

    public user: any;
    public app: any;
    public layout: any;
    public bodyHeight: string;

    constructor() {

        // User Settings
        // -----------------------------------
        this.user = {
            name: 'John',
            job: 'ng-developer',
            picture: 'assets/img/user/02.jpg'
        };

        // App Settings
        // -----------------------------------
        this.app = {
            name: 'angular 4',
            year: ((new Date()).getFullYear())
        };

        // Layout Settings
        // -----------------------------------
        this.layout = {
            isFixed: true,
            isCollapsed: false,
            isBoxed: false,
            isRTL: false,
            horizontal: false,
            isFloat: false,
            asideHover: false,
            theme: null,
            asideScrollbar: false,
            isCollapsedText: false,
            useFullLayout: false,
            hiddenFooter: false,
            offsidebarOpen: false,
            asideToggled: false,
            viewAnimation: 'ng-fadeInUp'
        };

    }

}

//Footer.Component.ts

import { Component, OnInit } from '@angular/core';
import { SettingsService } from '../../core/settings/settings.service';

@Component({
    selector: '[footer]',
    templateUrl: './footer.component.html',
    styleUrls: ['./footer.component.scss']
})
export class FooterComponent implements OnInit {

    constructor(public settings: SettingsService) { }

    ngOnInit() {

    }

}


//Footer.Component.html


<span>&copy; {{settings.user.name}} - {{ settings.user.job}}</span>