Let say I have a constant variable
const STATUS = {
ACTIVE: "ACTIVE",
DELETED: "DELETED",
}
And I have a function which input is status
const handleStatus = (status) {
//do some thing
}
I want to define interface for status
just accept 'ACTIVE' and 'DELETED' so I have to manually define like bellow
type status = 'ACTIVE' | 'DELETED'
const handleStatus = (status : status) {
//do some thing
}
Can I do something like
type status = Object.values(STATUS)
Thanks!
Edit :
I define type status = (typeof STATUS)[keyof typeof STATUS]
But when I try to check if status is valid
const validStatus = Object.values(STATUS)
if(!validStatus.includes(status)) {
//do something
}
Typescript throw error
Argument of type 'string' is not assignable to parameter of type ...
CodePudding user response:
There're 2 options for you. As a suggestion in comment to switch using enum
in this case, another way is to use keyof
keyword in terms of still wanting to have a string literal as type:
type Status = keyof typeof STATUS;
PS: If you prefer the values as type rather than the keys, you need to tweak a bit more:
const STATUS = {...} as const // mark it as constant
type Status = (typeof STATUS)[keyof typeof STATUS];
Answer for newly added request
Looks like misunderstand between typing vs its value. You can't set a type as value which means you have to create a variable with the type you already defined (Don't define a type name as lowercase status
) so here's the example:
type Status = (typeof STATUS)[keyof typeof STATUS];
// this is the value which needs to create with your created type
const status: Status = 'ACTIVE';
// you can set this type as: `Status[]` or
// you don't need to do so cause
// tsc can infer correct type as `Status[]`
const validStatus = Object.values(STATUS);
if(!validStatus.includes(status)) {
// ...
}