How to Pass a JavaScript Function as a Parameter Without Executing It?

How to Pass a JavaScript Function as a Parameter (Without Execution)

When passing functions as parameters, it's crucial to avoid immediate execution within the "parent" function. This prevents unwanted side effects and potential security concerns with practices like eval().

Solution:

To pass a function as a parameter without immediate execution, simply remove the parentheses from its name:

addContact(entityId, refreshContactList);

This passes the function reference instead of calling it, allowing you to execute it later within the callback function.

Example:

Consider the following scenario:

function addContact(id, refreshCallback) {
    refreshCallback();
    // You can also pass arguments if you need to
    // refreshCallback(id);
}

function refreshContactList() {
    alert('Hello World');
}

addContact(1, refreshContactList);

In this example, the addContact function receives two parameters: entityId and refreshContactList. The refreshContactList function is passed as a reference without immediate execution. Within the addContact function, the refreshContactList function is invoked, triggering the alert.

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