javascript - 流 : transforming union type of multiple strings into new type

Question

假设我有这种类型:

导出类型 VerificationStatus =
| 'TRIAL_DEPOSIT_PENDING'
| 'TRIAL_DEPOSIT_REQUIRED'
| '试用_存款_过期'
| 'TRIAL_DEPOSIT_VERIFICATION_FAILED'
| 'TRIAL_DEPOSIT_REINITIATE'
| '已验证';

我有一个散列映射，可能看起来像:

verificationStatus: { trial_deposit_expired: '抱歉，试用存款已过期。' },

等，其中每个键值对的名称应该是上面的联合之一，转换为小写。如何将它变成 VerificationMapKey 类型，这样我就可以做:const verificationStatus: {[name: VerificationMapKey]: string}?

换句话说，VerificationMapKey 是一个函数的返回类型，它遍历 VerificationStatus 的所有可能值并将它们变成小写。

Answer 1

简单如:

const VerificationStatuses = ['TRIAL_DEPOSIT_PENDING',
  'TRIAL_DEPOSIT_REQUIRED',
  'TRIAL_DEPOSIT_EXPIRED',
  'TRIAL_DEPOSIT_VERIFICATION_FAILED',
  'TRIAL_DEPOSIT_REINITIATE',
  'VERIFIED'];

const VerificationStausMessagesKey = VerificationStatuses.forEach(status => status.toLowerCase());

export type VerificationStatus = $Keys<typeof VerificationStatuses>;
export type VerificationStausMessageKey = $Keys<typeof VerificationStausMessagesKey>;