JavaScript - Functions

 

1. System function

　　JavaScript built-in function

 

2. Custom Functions

 　　I have written a function

function function name (parameter 1, parameter 2, ...) { 
    function body 
    return ; 
}

 

Call the function: function name (parameter 1, parameter 2, ...);

Incoming parameter argument function less than, the excess parameter is undefined function, if the real reference parameter is large, the extra arguments not processed

JavaScript does not support function overloading, if there are multiple functions of the same name, the last defined function is called