caller Property (Function) (JavaScript)

The functionName object is the name of any executing function.

The caller property is defined for a function only while that function is executing. If the function is called from the top level of a JavaScript program, caller contains null.

If the caller property is used in a string context, the result is the same as functionName.toString, that is, the decompiled text of the function is displayed.

The following example illustrates the use of the caller property:

function CallLevel(){
   if (CallLevel.caller == null)
      return("CallLevel was called from the top level.");
   else
      return("CallLevel was called by another function.");
}

document.write(CallLevel());

// Output: CallLevel was called from the top level.

Supported in the following document modes: Quirks, Internet Explorer 6 standards, Internet Explorer 7 standards, Internet Explorer 8 standards, Internet Explorer 9 standards, Internet Explorer 10 standards. Also supported in Windows Store apps. See Version Information.

Reference