基本类型
基本类型有boolean、number、string、array、void。所有类型在TypeScript中，都是一个唯一的顶层的Any Type 类型的自类型。any关键字代表这种类型。
| 类型 | 声明方式 |
|---|---|
| boolean | var isDone:boolean=false |
| number | var height = 6; |
| string | var name:string="bob |
| array | var list:number[]=[1,2,3] |
| enum | enum Color {Red,Green,Blue} |
| any | var notsure:any = 4;notsure = "maybe a string instaed"; notsure = false; |
在TypeScript中，我们不能把null或undefind当作类型使用。
var testVar : null;//错误，类型错误
var testVar : undefined;//错误，找不到undefined
var、let和const
在TypeScript中，当声明一个变量时，可以使用var、let和const关键字
var mynum = 1;
let isValid:boolean = true;
const PI : number = 3.141592654;
联合类型
var path :string[]|string;
path = '/temp/log.xml';
path = ['/temp/log.xml','/temp/error.xml'];
类型别名
TypeScript允许用type关键字声明类型别名
type PrimitiveArray = Array<string|number|boolean>;
type MyNumber = numbe;
type NgScope = ng.IScope;
type Callback = () => void;
函数
1.具名函数
function greet(name?:string):string{
if(name){
return "Hi," + name;
}else{
return "Hi!";
}
}
2.匿名函数
var greet:(name?:string) => :string = function(name:string):string{
if(name){
return "Hi," + name;
}else{
return "Hi!";
}
}
类
class Character{
fullname:string;
constructor(firstname:string,lastname:string){
this.fullname = firstname + " " + lastname;
}
greet(name?:string){
if(name){
return "Hi!" + name + "!my name is " + this.fullnamel;
}else{
return "Hi! my name is " + this fullname ;
}
}
}
var spark = new Character("Jacob","Keyes");
var msg = spark.greet();//"Hi! my name is Jocob Keyes";
var msg1 = spark.greet("Dr. Halsey");//"Hi!Dr. Hasey! my name is Jacob Keyes"
