For this reason, in the past, many developers decided to add all their form validation logic exclusively to server-side code.Hello, I have 2 asp textbox, 2 radtextbox and 4 asp Regular Expression Validator and one button in my page.
The problem, however, is that it does not work with all browsers.Not all browsers support Java Script, and different versions of browsers support different versions of Java Script, so client-side validation is never guaranteed to work.To validate input captured with server controls, you can use the Regular Expression Validator control. Input validation can become a security issue if an attacker discovers that you have made unfounded assumptions.To validate other forms of input, such as query strings, cookies, and HTML control input, you can use the System. The attacker can then supply carefully crafted input that compromises your application by attempting SQL injection, cross-site scripting, and other injection attacks.The advantage of writing validation logic in client-side code is that you can provide instant feedback to your users.
For example, if a user neglects to enter a value in a required form field, you can instantly display an error message without requiring a roundtrip back to the server. It looks great and creates a better overall user experience.
Use this property to specify the pattern used to check for predictable sequences of characters, such as those in social security numbers, e-mail addresses, telephone numbers, and postal codes.
The Regular Expression Validator does not perform validation on an empty string. This example has a text box that accepts user input, which is a potential security threat. NET Web pages validate that user input does not include script or HTML elements.
If i have the rad Scriptmanager in this page validation will not work on button click and page will postback without validating it.
If i remove the script manager from this page then validation will work on Button Click and page will not postback.
on the button onclientclick iam validating the subject textbox and the fckeditor whether they are empty or not and if they are iam asking for confirmation if iam not using this clientclick then regular expression is working fine but if iam using it is not validating at all it is just asking for confirmation and on clicking ok it is sending the email.