What is the process for setting the values of an object within a constructor to all class properties?

I am attempting to easily transfer all the properties from an object in a constructor to a class's properties

type tCustomUpload = {
    name : string,
    relationship : string,
    priority : number,
    id : number
}
class CustomUpload {
    name : string;
    relationship : string;
    priority : number;
    id : number;
    constructor (payload : tCustomUpload) {
        Object.assign(this, payload);
    }
}

I experimented with the solution on How to assign values to all properties of class in TypeScript?, but encountered 2 issues with that approach

  1. the interface contains optional properties, while I require them to be mandatory
  2. typescript raises errors for that solution stating something like
    Property 'x' has no initializer and is not definitely assigned in the constructor.

ts playground

Answer №1

When using TypeScript, the approach of iterating over properties to assign them with Object.assign may not work as expected. A workaround for this is to use assertion operators like !: to ensure that the properties exist.

interface CustomData {
    name: string,
    role: string,
    age: number,
    id: number
}
class DataHandler {
    name!: string;
    role!: string;
    age!: number;
    id!: number;
    
    constructor(data: CustomData) {
        Object.assign(this, data);
    }
}

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