ASP Regular expression to check length of textbox value

Hi, here is a regular expression validator in ASP which you can use to check if a certain textbox has less than a certain number of characters.

<asp:regularexpressionvalidator runat="server" id="lengthRegex" controltovalidate="">" validationexpression=".{1,<n>}" errormessage="Please note that there should be less than <n> number of characters in the textbox"> </asp:regularexpressionvalidator>

So, if you intend to make the textbox accept a number of characters in a range(say between 5 to 10) then the following changes would work

<asp:regularexpressionvalidator runat="server" id="lengthRegex" controltovalidate="">" validationexpression=".{5,10}" errormessage="Please note that there should be between 5 to 10 characters in the textbox"</asp:regularexpressionvalidator>

Suppose you need to limit the characters to only alphanumerics, then use the following regular expression for the validator.

"[A-Za-z0-9]{5,10}"

Now, suppose you only wish to have a certain number of special characters only. Say you need to accept the space( ) period(.) , comma(,) and dash(-) only with the alphanumerics. Then use the following regex.

"[A-Za-z0-9.-,\s]{5,10}"

You can modify the above code for your custom needs.
Have fun.

Comments

Abhi said…
Really Very Usefull information. It solves lot of my problems....ThanQ
March 13, 2010 at 7:08 AM
Nguyễn Minh Tuấn said…
This comment has been removed by the author.
November 3, 2010 at 12:13 PM
Post a Comment

Popular posts from this blog

Encrypt and Decrypt Images Using Java

Hi, Most of you would find it useful to Encrypt a special picture of yours such that only you can view it. By using JCE(Java Cryptography Extension) classes, this becomes very simple. As I have already done before using Java to encrypt a String is very simple. If you are new to this, please read the article which I had already posted named "Java Encryption and Decryption" at "http://ruchiram4.blogspot.com/2009/04/java-encryption-and-decryption.html" Also, you need to have a basic understanding of Java IO. If you are new, it is better to read the Sun Java tutorial on IO. Before we move on, lets recall the basic steps in Encrypting plaintext. 1. Creating an instance of "Cipher" object and setting the mode of Encryption (Eg: AES, DES) 2. Generating a key by using a KeyGenerator object. 3. Setting the mode of Cipher operation on the Cipher object. As we intent to Encrypt, we simply set it by setting a property of Cipher object by calling its "init"
Read more

Build your own Network sniffer

Image
Recently, I ve been developing a tool to monitor the Network Traffic as an assignment. Here, I wish to share my experience with all of you who are interested in building your own Sniffer. Prerequisites : Java Programming capability, Knowledge on OOP(Object Oriented Programming) basics My Environment: I used the libraries specified for Java which is widely available. I ran my application on Windows XP only. But the libraries can be easily integrated with Linux based systems. I used NetBeans 6.1 version for development activities. But any other java IDE would do In setting up the environment, first you need to download Jpcap jar found at http://sourceforge.net/projects/jpcap Once you download this, you have to add this to your NetBeans project. It can be done as follows. After adding the Jar file to the project, you need to download the WinPCap driver. It can be easily downloaded from http://www.winpcap.org/ It is required to get low level networking access regarding packets. As for
Read more

ASP Response.Write newline

Hi, all of you who have used ASP may have encountered situations where you require to write a text output to the screen. It can be easily done by using Response.Write("Hello world"); However, if you wish to append some more text to a newline, it would not work in the following ways. Response.Write("Hello world \n"); Response.Write("Good day."); The output of the above lines would be Hello world Good day. and NOT Hello world Good day. In order to overcome this, you can very simple place an html break tag inside the code. Response.Write("Hello world"); Response.Write("<br/>"); Response.Write("Good day."); The output would be the following. Hello world Good day. Cheers !!!
Read more