Sometimes, we want to create a function interface with TypeScript.
In this article, we’ll look at how to create a function interface with TypeScript.
How to create a function interface with TypeScript?
To create a function interface with TypeScript, we can put the signature and return type of the function in an interface.
For instance, we write
interface IFormatter {
(data: string, toUpper: boolean): string;
}
const upperCaseFormatter: IFormatter = (data: string) => {
return data.toUpperCase();
};
to create the IFormatter interface that requires a function to have signature that some or all of the parameters in (data: string, toUpper: boolean) and returns a string.
We can then create the upperCaseFormatter function with type IFormatter and with the data string parameter and returns a string.
Conclusion
To create a function interface with TypeScript, we can put the signature and return type of the function in an interface.
