我想用一个变量保存类实例数组，元素类型要允许任何从某个“基类”派生的实例。这个类实例数组的例子能更清楚地说明我的意思。
class Parent { } //Common parent
class FirstChild extends Parent { }
class SecondChild extends Parent { }
//How should this declaration look?
let instances: <U extends Parent>U[] = []; //Allow all descedants of 'Parent' here
//Then these calls would work
instances.push(new Parent());
instances.push(new FirstChild());
instances.push(new SecondChild());先谢谢大家。
I'd like a variable holding an array of class instances, with its element type allowing anything derived from a 'base' class. This example of the class-instance array explains what I mean:
class Parent { } //Common parent
class FirstChild extends Parent { }
class SecondChild extends Parent { }
//How should this declaration look?
let instances: <U extends Parent>U[] = []; //Allow all descedants of 'Parent' here
//Then these calls would work
instances.push(new Parent());
instances.push(new FirstChild());
instances.push(new SecondChild());Thank you beforehand.
试试这种写法
let instances: Array<Parent> = [];例子就在上面
你的类实例数组也可以用这种方式
type Family = Parent | FirstChild | SecondChild;
let instances: Array<Family> = new Array<Family>();One option for your class-instance array is
type Family = Parent | FirstChild | SecondChild;
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