typescript - TS : Index signature for type 'string' is missing in type 'IParam'

Question

interface Param {name: string, age: number}

const p: Param = {name: 'tt', age: 18}

const foo = (object: {[key: string]: unknown}) => {
    // ...something
}

foo(p) 

// Argument of type 'Param' is not assignable to parameter of type '{ [key: string]: unknown; }'.
  Index signature for type 'string' is missing in type 'Param'.

我传入的类型和函数参数的类型一致，为什么会报错？

Answer 1

您的动态参数应该是any，而不是unknown

const foo = (object: {[key: string]: any}) => {
    // ...something
}

您可以查看this document为了更好地理解未知类型

[..] Much like any, any value is assignable to unknown; however, unlike any, you cannot access any properties on values with the type unknown, nor can you call/construct them. Furthermore, values of type unknown can only be assigned to unknown or any.

这意味着您无法将值分配给代码中的unknown

foo(p) //assign values to `unknown` type params