JavaScript handler.deleteProperty() method in JavaScript is a trap for the delete operator. This method returns the boolean value if the delete was successful.
Syntax:
const p = new Proxy(target, {
deleteProperty: function(target, property) {
}
});
Parameters: This method accepts two parameters as mentioned above and described below:
- Target: This parameter holds the target object.
- Property: This parameter holds the name of the property which is to be deleted.
Return value: This method returns a Boolean value that indicates whether the property was successfully deleted.
Example 1: In this example, we will trap a delete operator using the handler.deleteProperty() method in JavaScript.
const monster1 = {
Color: ‘Green’
};
const handler1 = {
deleteProperty(target, prop) {
if (prop in target) {
delete target[prop];
console.log(`${prop} is property which is removed`);
}
}
};
console.log(monster1.Color);
const proxy1 = new Proxy(monster1, handler1);
delete proxy1.Color;
console.log(monster1.Color);
let f = { bar: ‘baz’ }
console.log(‘bar’ in f)
delete f.bar
console.log(‘bar’ in f)
Output:
"Green" "Color is property which is removed" undefined true false