JavaScript: Check whether an object contains specified property

JavaScript Object: Exercise-17 with Solution

Check Property Existence

Write a JavaScript function to check whether an object contains a given property.

Sample Solution:

JavaScript Code:

function hasKey(obj, key) {
    return obj != null && hasOwnProperty.call(obj, key);
  }
console.log(hasKey({red: "#FF0000", green: "#00FF00", white: "#FFFFFF"}, "green"));

Output:

true

Flowchart:

Live Demo:

See the Pen javascript-object-exercise-17 by w3resource (@w3resource) on CodePen.

For more Practice: Solve these Related Problems:

• Write a JavaScript function that checks if an object contains a given property using the in operator.
• Write a JavaScript function that verifies property existence using hasOwnProperty() to exclude inherited properties.
• Write a JavaScript function that accepts a property name and an object, then returns a boolean indicating its presence.
• Write a JavaScript function that checks for a property in an object and returns a custom message if not found.

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