JAVASCRIPT

same onclick function on different elements and change another element

<button type="button" onclick="myFunction(this)" id="1">Button1</button>
<button type="button" onclick="myFunction(this)" id="2">Button1</button>
<button type="button" onclick="myFunction(this)" id="3">Button1</button>

function myFunction (button) {
    var x = button.id;
    switch (x) {
        case '1':
            myFunction1(x);
            break;
        case '2':
            myFunction2(x);
            break;
        case '3':
            myFunction3(x);
            break;
        default:
            return false;
    }
}