Once you have an HTML form up and running, you will often want to make sure that all the important fields are filled in.For example, if you are going to send an email confirmation letter, the email address should be included in the form fields, and it should be an email address that works.Let us set default values for some of the form elements.For instance, the following snippet of code sets the default for the radio element named “business_category” to the value 3.In the head portion of your HTML, you should create a script to do the form validation: See the validation script in action.Page 4: Use a Perl CGI script to validate your HTML forms.
Below are the ways to get the value from all types of form elements.
This can make filling out the form tedious, and people might stop in the middle.
If you use the following script and Perl source you will know how to validate an entire form at once, displaying a series of error messages that your reader can then go back and fix.
There are two ways to validate your forms: The basic premise of creating form validation is to look for the names of form elements that are required, and if they are empty, display an error message.
Most error checking programs check each field one at a time, and display one error at a time.