Replace text in a div

[happyharry]

I know how to replace text inside a given div:
document.getElementById("containerID").innerHMTL = "some new text";

But I want to change text depending on text that is in an array.

So I have an array:

my_array =
{
'Good' : 'Bad',
'Happy' : 'Sad',
}

How can I change the text in a div with the key of the array? So if my div contains the word good I want to change it to bad.

[happyharry]

woops! wrong place! supposed to be in the javascript section.