The user has to input a 'serial' that can be verified in a database. The user can enter 1 to n 'serials'. Serials can be good or bad.
For those following case, I do:
- Case 1: Do the process on good serial, let only the bad serials.
- Case 2: Input invalid no process.
- Case 3: Clear the textbox, all process done.
User can observe immediately the rest of the process so they know if it works or not. But finding the serial that failed in a list even a short one can be hard. As they can look like the same. The user enters 1 to 10 serial in a row. The average number is 4.
Color can not be use in the text box as textbox is rendered as HTML
<input> element on the page.
Input can be validated on key strokes, but it will be time-consuming as checking for a like on 3 million row will take more time than an equal test.
The input takes 20% of the display. So 80% of it is free for any error message.