JavaScript function.caller Property
The function.caller property of the JavaScript function object returns the function that invoked the specified function. It returns null if the function “f” was invoked by the top-level code in JavaScript. For functions like strict functions, async functions and generator function this method returns null.
Syntax:
function.caller
Parameters: This function does not accept any parameter.
Return Value: This function returns null for strict, async function and generator function callers.
Few examples are given below for a better understanding of the function methods.
Example 1:
HTML
<!DOCTYPE html><html lang="en"> <head> <meta charset="UTF-8"> <meta name="viewport" content= "width=device-width, initial-scale=1.0"></head> <body> <script> // Creating func2 function func2() { console.log("This is from function 2") } // Creating func1 function func1() { func2(); } // Call Function 1 func1(); // null is returned as function // is strict, async function and // generator function console.log("from function.caller: ", func1.caller) </script></body> </html> |
Output:
Example 2:
HTML
<!DOCTYPE html><html lang="en"> <head> <meta charset="UTF-8"> <meta name="viewport" content= "width=device-width, initial-scale=1.0"></head> <body> <script> function myFunc() { if (myFunc.caller == null) console.log("The function " + "was called from the top!"); else console.log("This function's " + "caller was " + myFunc.caller); } myFunc() </script></body> </html> |
Output:
Browsers Supported:
- Google Chrome
- Microsoft Edge
- Mozilla Firefox
- Internet Explorer
- Safari
- Opera
