Java validating standard input
For numeric fields, there is a convenient way to validate a value range, but we want to select to run a custom validation script.
After the “Edit” button is clicked, a new window will open that allows us to edit the new script: This script also includes a check for an empty string, so that the user can wipe out a wrong string and start from scratch.
If the input field comes from a fixed set of options, like a drop down list or radio buttons, then the input needs to match exactly one of the values offered to the user in the first place.
Free-form text, especially with Unicode characters, is perceived as difficult to validate due to a relatively large space of characters that need to be whitelisted.
In that case, the previous value of the field is restored, and the user has to enter the data again.
Then we select the “Validate” tab to see the validation options: The default is that the field will not get validated.
There are other ways to highlight the field in question besides changing the text color, the border color or the fill color could be changed instead, or in addition, just make sure that you are not making the form impossible to read.
To learn more about the event object, take a look at JS.88.560– make sure to click on the button in the upper left corner to display the navigation pane if it’s not shown automatically.
If it's well structured data, like dates, social security numbers, zip codes, e-mail addresses, etc.
then the developer should be able to define a very strong validation pattern, usually based on regular expressions, for validating such input.