You either declare your function like this:
window.handler = function() {
// function code here
};
if (window.handler) { // check if the function actually exist
window.handler(); // call the function
}
or you change the if to:
if (typeof handler === 'function') {
handler();
}
if you want to check if a function exists, do it in this way:
if (window.alertHandler)
alertHandler();
if (window.myFunc()) runs function first and check the return value. but if (window.myFunc) doesn't run it just check if myFunc exists in window object.
To invoke this function as method of the window object first you must make it a method of the window object.
function somefunction(){
// ...
}
window.handler = somefunction;
//NOW you can reference it like that
window.handler();
As shown in another answer you can also assign an anonymous function directly.
