Thanks, Thomas!
I can understand the desire to do this, but there really should be something to prevent a double transaction in the code behind instead of relying on disabling buttons.
Presumably, if you click the "Place Order" button, it will cause a page load event. However, let's assume the user clicks the button, but (for whatever reason) the new page is loading slowly and the old page is still displaying.
This leaves the Place Order button clickable while the new page is loading. Code behind should prevent additional transactions from erroneous clicks to the Place Order button.
I'll go over this in a little more detail in the follow-up article, but what if the button is hidden upon the click event (or double-click event) and there's an alert stating that the order is processing (or something of that nature). This assumes that there is some code behind to prevent a double transaction. Then the new page loads.
All that to say, it's still good practice not to disable the button - but out of all the scenarios to do it, this one would probably cause the least amount of issues.
Thanks again!