Calling an event handler with an argument [duplicate]

Answer 1

You are trying to assign the return value of changeColor() to box.click() instead of the function itself. Wrapping changeColor() in a function as follows sets the box.click() to the function

box.click(function(){
   changeColor.call(this, "green")
});

See Fiddle

Answer 2

var box = $("#box");

function changeColor (a) {
    $(this).css("background", a);
}

box.click(function(){
   changeColor("green");
});

Answer 3

You are calling your changeColor function instead of passing it as callback. Instead you should do :

box.click(changeColor.bind(this, "green"));

The bind method creates a new function with arguments already filled, it is almost equivalent to doing :

box.click(function () {
    changeColor("green");   
});

Answer 4

Use .call()

Fiddle Demo

box.click(function(){
   changeColor.call(this, "green");
});

Answer 5

You need to use call() to call your function inside click event:

var box = $("#box");

function changeColor (a) {
    $(this).css("background", a);
}

box.click(function(){
   changeColor.call(this, "green");
});

Fiddle Demo