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JavaScript jQuery Basics (2014) Creating a Simple Drawing Application Perform: Part 2

Lucian Dumitru
PLUS
Lucian Dumitru
Courses Plus Student 13,024 Points

Why aren't you using parentheses when calling the changeColor() function ?

Considering the following line of code:

$("input[type=range]").change(changeColor);

Why is he using

.change( changeColor ); //the function is called without parentheses 

and not

.change( changeColor() );

Can someone explain? I'm a little bit confused.

1 Answer

Steven Parker
Steven Parker
229,732 Points

The function is not being called.

In this case, the function itself, and not the result of calling it, is being passed as a parameter to establish an event handler. It will be invoked later by the system when a change event occurs on range input element.

Functions used this way are often called callback functions.