Define mandantory Datatype for Arrays in TypeScript

I want to define a jsonArray and also the datatypes, which have to be used.

My first approach was this one hear:

felder = [{ elementId: string, // elementId: '' would work value: string, inputType: string }]; constructor() { this.felder.push({elementId: 'ID1', value: 'First', inputType: 'input'}); this.felder.push({elementId: 'ID2', value: 'Second', inputType: 'dropdown'}); this.felder.push({elementId: 'ID3', value: 'Third', inputType: 'checkbox'}); } 

But it does not work. The error message is:

string' only refers to a type, but is being used as a value here.

I understand the error but cannot find a solution. How can I define a must-used datatype?

Thanks & Best Regards

1 Answer

Use an interface:

interface MyInterface { elementId: string; value: string; inputType: string; } class MyClass { public felder: MyInterface[] = []; constructor() { this.felder.push({elementId: 'ID1', value: 'First', inputType: 'input'}); this.felder.push({elementId: 'ID2', value: 'Second', inputType: 'dropdown'}); this.felder.push({elementId: 'ID3', value: 'Third', inputType: 'checkbox'}); } }