how to make global variable in angular

Here is the simplest solution w/o Service nor Observer:

Put the global variables in a file an export them.

//
// ===== File globals.ts    
//
'use strict';

export const sep='/';
export const version: string="22.2.2";    
To use globals in another file use an import statement: import * as myGlobals from 'globals';

Example:

// 
// ===== File heroes.component.ts    
//
import {Component, OnInit} from 'angular2/core';
import {Router} from 'angular2/router';
import {HeroService} from './hero.service';
import {HeroDetailComponent} from './hero-detail.component';
import {Hero} from './hero';
import * as myGlobals from 'globals'; //<==== this one (**Updated**)

export class HeroesComponent implements OnInit {
    public heroes: Hero[];
    public selectedHero: Hero;
    // 
    //
    // Here we access the global var reference.
    //  
    public helloString: string="hello " + myGlobals.sep + " there";

         ...

        }
    }
Thanks @eric-martinez