Optional Arguments - JsPlayground 2022

By using a ? to define an argument, you make it optional (nullable). x & y are required but z is not. When this technique is used, be sure to test for the optional arguments.


function CalculateStuff (x: number, y: number, z?: number)
{
    var results: number;
    if (z === undefined)
    { results = x + y;}
    else
    { results = x + y + z;}
    return results;
}
console.log("results without z: " + CalculateStuff(7, 7));
console.log("results with z: " + CalculateStuff(7, 7, 7));