1. class DataManager {
    2.     constructor(private data: string[] | number[]) { }
    3.   getItem(index: number):string | number {
    4.       return this.data[index]
    5.   }
    6. }
    8. class DataManager<T> {
    9.     constructor(private data: T[]) { }
    10.   getItem(index: number):T {
    11.       return this.data[index]
    12.   }
    13. }
    15. const data = new DataManager<number>([1])
    17. const data = new DataManager([1])
    18. data.getItem(0)
    20. interface Item {
    21.     name: string
    22. }
    24. class DataManager<T extends Item> {
    25.     constructor(private data: T[]) { }
    26.   getItem(index: number):T {
    27.       return this.data[index].name
    28.   }
    29. }
    31. const data = new DataManager([
    32.   {
    33.       name: 'Jack'
    34.   }
    35. ])
    37. interface Test {
    38.     name: string
    39. }
    41. class DataManager<T> {
    42.     constructor(private data: T[]) { }
    43.   getItem(index: number):T {
    44.       return this.data[index]
    45.   }
    46. }
    48. // 泛型对应的具体类型是Test
    49. const data = new DataManager<Test>
    51. class DataManager<T extends number | string> {
    52.     constructor(private data: T[]) {}
    53.   getItem(index: number): T {
    54.       return this.data[index]
    55.   }
    56. }
    58. const data = new DataManager<string>([])
    1. const func: <T>(param: T) => T = <T>(params: T) => {
    2.     return params
    3. }