Mastering TypeScript 3 - Third Edition

Constructor access modifiers

TypeScript also introduces a shorthand version of the constructor function, allowing you to specify parameters with access modifiers directly in the constructor. Consider the following code:

class classWithAutomaticProperties { 
    constructor(public id: number, private name: string){ 
    } 
} 
 
let myAutoClass =  
    new classWithAutomaticProperties(1, "className"); 
console.log(`myAutoClass id: ${myAutoClass.id}`); 
console.log(`myAutoClass.name: ${myAutoClass.name}`); 

This code snippet defines a class named ClassWithAutomaticProperties. The constructor function uses two arguments—an id of type number, and a name of type string. Note, however, the access modifiers of public for id and private for name, defined directly in the ...