JavaScript - document.getElementByID with onClick

Perhaps you might want to use "addEventListener"

document.getElementById("test").addEventListener('click',function ()
{
    foo2();
   }  );

Hope it's still useful for you

In JavaScript functions are objects.

document.getElementById('foo').onclick = function(){
    prompt('Hello world');
}

The onclick property is all lower-case, and accepts a function, not a string.

document.getElementById("test").onclick = foo2;

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