Question

当前，尝试在Typescript中创建新对象时出现奇怪的行为。有两类：

export class SkaterDrawn {

    private ID;
    private name;
    ...

constructor(input?:any) {
    this.ID = input.ID;
    ...
}


export class SkaterDrawnTeam extends SkaterDrawn {
    private skaters:SkaterDrawn[];

    constructor(skaters:SkaterDrawn[]) {
        super(skaters[0]);
        this.skaters = skaters;
    }
    ...
}

this.registeredSkaters包含类型为SkaterDrawn的元素数组。现在，我将该数组分组为一个大块数组，如下所示：

this.registeredSkaters = this.registeredSkaters.groupBy('teamID');
this.registeredSkaters = Object.values(this.registeredSkaters);

这将输出：

[
    [SkaterDrawn,SkaterDrawn,SkaterDrawn],
    [SkaterDrawn,SkaterDrawn,SkaterDrawn],
    [SkaterDrawn,SkaterDrawn,SkaterDrawn]
]

现在我正尝试以此创建一个新对象：

let teams = this.registeredSkaters.map((item:SkaterDrawn[]) => 
    new SkaterDrawnTeam(item);
})

我期望得到一个SkaterDrawnTeam的数组，但是编译失败并显示

ERROR in src/app/competition/components/drawing/drawing.component.ts(166,30): 
error TS2345: Argument of type 'SkaterDrawn' is not assignable to parameter of type 'SkaterDrawn[]'.
Type 'SkaterDrawn' is missing the following properties from type 'SkaterDrawn[]': length, pop, push, concat, and 35 more.

Line 166,30是我尝试做的行new SkaterDrawnTeam(item)，我不知道为什么会失败。我在做什么错了，我该如何解决？

非常感谢您的帮助。

Answer 1

问题在于SkaterDrawn []与（typeof SkaterDrawn）[]

不同

let teams = this.registeredSkaters.map((item: (typeof SkaterDrawn)[]) => { 
               return new SkaterDrawnTeam(item);
             });

然后将您的班级更改为

export class SkaterDrawnTeam extends SkaterDrawn {
    private skaters:(typeof SkaterDrawn)[];

    constructor(skaters:(typeof SkaterDrawn)[]) {
        super(skaters);
        this.skaters = skaters;
    }
}

https://stackblitz.com

错误TS2345：类型'X'的参数不能分配给类型'X []'

1 个答案: