Saving Old Value
testing saving value
by mark edwards
HTML
<input id='marksTest' onFocus="this.oldValue = this.value;" type='text'/>
<button type='button'
onClick='javascript: console.log("NEW VALUE: " + document.getElementById("marksTest").value);
console.log("OLD VALUE: " + document.getElementById("marksTest").oldValue);'>
Click to show values in console
</button>
<p>
https://stackoverflow.com/questions/1909992/how-to-get-old-value-with-onchange-event-in-text-box/8419309#comment123057316_8419309
</p>
<p>
open browser console, click button, enter value, click button, CHANGE value, click buttton again
</p>