selector for text element within another element

selector for text element within another element

Hi,

I am very new in JQuery..

If I have something like this

<div class="myDiv">
      <span> Test </span>
</div>

If the text inside the span changed I need to do something.. for example if "Test" inside span has been changed dynamically into "Test2" I need to do something..

Can you help me how can I approach that? I mean what kind of selector should i use to select "text" in span element within the div with class"

Many thanks