03. Getting Properties in an Object

Updating Properties

To update the properies, we simply use the assignment operator after using either the member operator (dot notation) or an array-like accession

// Two ways to update our car color
carInstance.color = "red";
carInstance["color"] = "red";

Looking for a property

If you want to find out if an object contains a property, you can use the in keyword with an if statement.

if ("color" in carInstance) {
  alert("This object has a color");
}

Looping through all properties

To loop through an object, with each name of the property, use a for...in loop.

for (var prop in carInstance) {
  alert("Property found: " + prop);
}

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