Converting data types in TypeScript function parameters

Modify a function's parameter type by forcefully casting it.

In the scenario displayed below:

(<number>foo)(1)

The original function definition is as follows:

function foo( v : string )

Answer №1

If you're unable to change the types of function parameters, one workaround is to type assert by casting the parameter as any:

function fn(obj: string) {
    ...
}

fn(1 as any);

Alternatively, you can make the function more generic by allowing multiple types:

function fn(obj: string | number) {
    ...
}

fn(1);
fn("str");

Another option is to use generics to maintain flexibility in the parameter type:

function fn<T>(obj: T) {
    ...
}

fn(1);
fn("str");

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