How to find out the caller function in JavaScript?

In this article, we see the methods to find out the caller function in Javascript. Sometimes, the developer may want to modify how a function works on the basis of its caller function. To find out the caller function name, we will use the Function object’s caller property.

Property:

• Function.caller

Here, the Function object is replaced by the name of the function of which we want to know the parent function name. 

Example 1: When the below code is executed, we can see the name of the parent function being logged out. 

javascript

<script>
    // Child function
    function Foo() {

    // This will print 'Bar'
        console.log(Foo.caller.name);
    }

    // Parent function
    function Bar() {
    Foo();
    }

    Bar();
</script>

Output:

 Bar 

Example 2: Suppose we call the Foo function from multiple functions. 

javascript

<script>
    // Child function
    function Foo() {

        // This will print parent function's name
        console.log(Foo.caller.name);
    }

    // Parent function
    function Geeks() {
        Foo();
    }

    // Parent function
    function Fun() {
        Foo();
    }

    // Parent function
    function Sam() {
        Foo();
    }

    Geeks();
    Fun();
    Sam();
</script>

Output:

Geeks
Fun
Sam

 You can know more about the parent function from the property Function.caller