作为函数的参数类型的定义

  2. interface labelobj{
  3.     label:string
  4. }
  6. function printLabel(lableObject: labelobj){
  7.     console.log(lableObject)
  8. }
  10. printLabel({label:"label"})

参数后面加上？表示可选参数

  2. interface labelobj{
  3.     label:string
  4.     width?: number
  5. }
  7. function printLabel(lableObject: labelobj){
  8.     console.log(lableObject)
  9. }
  11. printLabel({label:"label"})
  12. printLabel({label:'abc',width:10})

readonly 不能修改的值

  1. interface Point{
  2.     readonly x:number
  3.     readonly y:number
  4. }
  6. let p1:Point = {x:10,y:5}
  7. p1.x = 20  // Cannot assign to 'x' because it is a read-only property.