类型别名
type strType = string|number|boolean;
var str:strType = "10";
str = 10;
str = true;
接口也可以采用类型别名
interface muchType1 {
name: string
}
interface muchType2 {
age: number
}
type muchType = muchType1 | muchType2
var obj: muchType = { name: "张三" }
var obj2: muchType = { age: 18 }
var obj3: muchType = { name: "张三"， age: 18 }
限制字符串的选择
type sex = '男'|'女'
function getSex(s: sex): string {
return s;
}
getSex('女') // 只能传 ‘男’或者‘女’
