JavaScript Single Field Validation - Example 1
Enter data into the fields below and press "Check Data" when done. This
will run a JavaScript for each field to validate it's contents. You are
only notified about one error at a time if there are more than one. A
success message is displayed when all entries are valid.
Source: View or Save this HTML file
to obtain the scripts used to do this validation. The scripts are part
of the file.