How to assign string | undefined to string in TypeScript?

Question

I want to assign a variable, which is string | undefined, to a string variable, as you see here:

private selectedSerialForReplace(): string | undefined {
            


        

Answer 1

If you are sure that serial could not be undefined you can use the ! post-fix operator

luminaireReplaceLuminaire({serial: this.selectedSerialForReplace()!, newserial: response.output});