Importantance of returning false It's very important to use the return false statement after the condition block that return false so if validation determines that the business requirements are not met then the form cannot be submitted.If you do not return false then the message will be displayed to the user that all fields are required but the form will be post back and it gives you the second page directly. The condition that checks both text boxes for word are as in the following: In the preceding condition, first we ensure that the email id is not blank then we match the email id entered into the text box to the Regular Expression that is saved in the email Exp variable.Each new user of Echo Link must provide proof of license before access is granted.This is to ensure that only licensed Amateurs have access to the system, and to ensure that each user is using a valid callsign that he or she is authorized to use.It can prevent people from leaving fields blank, from entering too little or too much or from using invalid characters.
Now click on the "Create" button; it will redirect to the next page as in the following: Note For detailed code please download the zip file attached above.
There are several different ways you can provide proof of license. The various options will be explained on the pages that follow.
Form validation normally used to occur at the server, after the client had entered all the necessary data and then pressed the Submit button.
Now add the condition to ensure that all controls have a value, if the values are not entered in the form control then it will show a message.
The condition will be as follows: is shown to the user and finally we are returning false; that is very important.
Server Side Validation Validation done at the server level after sending the form data to the server but before entering the data into the database is called server-side validation. The first page source code Look at the preceding source code closely; see the id's of controls that play the important role in Java Script validation by reading the ASP. The design view of the preceding source code will look as in the following: I hope you have created the same form as above for demonstration purposes. Net controls values in Java Script are as: There are three main methods shown in the above image in the red square to read the ASP.