Question

我有一个基于基础的枚举，例如BasedColor，我想在另一个枚举中用作AnotherState。无论如何，都可以使用相同的键覆盖该值。所以我不需要重复键代码。我想我可以创建一个新的枚举，并将键abd分配给另一个值。但我想知道在打字稿中是否有更好的方法

enum BasedColor 
{
    First= 'red',
    Second = 'blue'
}

enum AnotherState
{
    First= 'light red',
    Second = 'light blue'
    Third = 'from another state third keu'
}

Answer 1

您可以这样做：

enum Colors
{
    First= 'red',
    Second = 'blue'
}

(Colors as any)['First'] = "Dark Red" // <== here

console.log(Colors.First)

Answer 2

TS中的

枚举只是对象。因此，您可以将它们分配给它们符合的接口，并可以使用扩展运算符...“扩展”一个。

// An interface for the keys a State can have
interface StateKeys {
    first: string;
    second: string;
    third?: string;
}

// Our base state, which we'll extend
enum BaseState {
    first = 'blue',
    second = 'red',
    third = 'magenta'
}

// Our custom state
enum AnotherState {
    first = 'light blue',
    second = 'light red'
}

现在我们可以看到扩展的工作原理：

// For the example, we'll just print the state's values
function doSomething() {
    console.log(currentState.first, currentState.second, currentState.third);
}

// Start with our state as the base state
let currentState: StateKeys = BaseState

doSomething(); // Prints "blue, red, magneta"

// Now we extend our base state with another state.
// Note, keys/values in objects to the right will overwrite ones to the left
currentState = {...BaseState, ...AnotherState};

doSomething(); // Prints "light blue, light red, magenta"

// You could also extend the *current* state instead:
currentState = {...currentState, ...AnotherState};

通过这种方式，您可以获得继承的值，但不必重写基础枚举，这可能导致意外行为，因为枚举在定义后应该是恒定的。

如何基于打字稿中的键覆盖枚举值

2 个答案: