How to give Validation on a text box

Hi Guys,

During Sales order posting i want to give validation in invoice round of field of Total Tab.

How can i do the same please help.

Can you please elaborate? Are you looking for some Development related help?

Yes, its development related,

During Sales order invoice posting there is an option(tab) Total, after click on total a new window will open and in this window there is a text box of Round off.
Now we can enter any value in this field but i want some validation should be here like enter value should be between -0.5 to +0.5.
Are u getting my point now?

You need to post it in right forum. I have moved it to developer forum.

Ok thanks.

Are you talking about sales totals form? Will you be able to post a screen shot?

Which version of AX are you talking about? Also, can you give us more information about the control, such as in which form it is and what is its datasource? If you make is easier for us, you’ll have a better chance that somebody will answer it.