Skip to main content

ASP.Net RegularExpressionValidator Control

RegularExpressionValidator control: The RegularExpressionValidator control is used to ensure that an input value matches a specified pattern.

·         The validation will not fail if the input control is empty. Use the RequiredFieldValidator control to make the field required.
·         Both server- and client-side validation are performed unless the browser does not support client-side validation or the EnableClientScript property is set to false.
·         You can validate email, URL or can specify your own regular expression to validate against input value.

RegularExpressionValidator additional Properties (Check here for other default properties and sample):

Property
Description
ValidationExpression
Specifies the expression used to validate input control. The expression validation syntax is different on the client than on the server. JScript is used on the client. On the server, the language you have specified is used

  Control usage:

<asp:TextBox runat="server" ID="txtNumber"></asp:TextBox>

<asp:RegularExpressionValidator ID="regNumeric" runat="server"
ControlToValidate=" txtNumber" ValidationExpression="\d{10}" EnableClientScript="false"
ErrorMessage="The entered value must be 10 numeric digits">
</asp:RegularExpressionValidator>

As I mentioned earlier you can also write your own regular expression and then use that with RegularExpressionValidator control. Let’s look at some of the character escapes, metacharacter and quantifiers used to write regular expression:

Character Escapes
Description
\b
Matches a backspace
\t
Matches a tab
\r
Matches a carriage return
\v
Matches a vertical tab
\f
Matches a form feed
\n
Matches a new line
\
Escape character
Metacharacters
Description
.
Matches any character except \n
[abcd]
Matches any character in the set
[^abcd]
Excludes any character in the set
\w
Matches any alphanumeric character and underscore
\W
Matches any non-word character
\s
Matches whitespace characters like, space, tab, new line etc.
\S
Matches any non-whitespace character
\d
Matches any decimal character
\D
Matches any non-decimal character
Quantifier
Description
*
Zero or more matches
+
One or more matches
?
Zero or one matches
{N}
N matches
{N,}
N or more matches
{N,M}
Between N and M matches

Comments

  1. This is a good tool to validate email addresses in .net:
    http://www.kellermansoftware.com/p-37-net-email-validation.aspx

    ReplyDelete

Post a Comment

Popular posts from this blog

Difference between Web API, WCF and Web Service

So now we have got the basic idea about Web API , now let’s do some comparison of Web API with WCF and web services. Web Service WCF Web API Web services are created as files with .asmx extension. WCF create with .svc extension Web API are simple class file with .cs(for C#) extension. Web API is inherited from “ApiController” and the class name must end with “Controller”. It is SOAP based service and returns data in XML form. It is also based on SOAP and returns data in XML form. Web API is HTTP based service and by default, it returns data in JSON or XML form. It supports only HTTP protocol. It supports various protocols like TCP, HTTP, HTTPS, Named Pipes, and MSMQ. It supports HTTP protocol. It can be hosted only on IIS. It can be hosted within the application or on IIS or using window service. It can be hosted within the application or on IIS. It is no...

C#: Merging Excel cells with NPOI HSSFWorkbook

In this post we’ll see how to merge the two or more cell with each other while creating the excel sheet using NPOI . Mentioned below is code to merge multiple cells, in this example we are merging first cell to fifth cell of first row (you can adjust row or cell range by passing particular parameters in CellRangeAddress). //Created new Workbook var hwb = new NPOI.HSSF.UserModel. HSSFWorkbook (); //Create worksheet with name. var sheet = hwb.CreateSheet( "new sheet" ); //Create row and cell. var row = sheet.CreateRow(0); var cell = row.CreateCell(0); ; //Set text inside cell cell.SetCellValue( "This is Merged cell" ); cell.CellStyle.WrapText = true ; //define cell range address // parameters: -> first row to last and first cell to last cell var cra = new NPOI.SS.Util. CellRangeAddress (0, 0, 0, 4); //Add merged region to sheet. sheet.AddMergedRegion(cra); Hope this solution helps you J

How to create RSS feed or Atom feed with .Net Syndication

Overview Every other website that routinely publishes contents provides syndication feed to its users. A syndication feed can be a static XML file that gets created automatically whenever new content is published or it can be a dynamic web page that gets the latest published items and provides the appropriate XML markup. A good example of data-sharing using XML is Web site syndication, commonly found in news sites and Web logs. Another example is Twitter provides feeds of user's most recent tweets. With the help of syndication feed, a Web site publishes its latest content in an XML-formatted file. Because it conforms to a known XML standard, its data can be parsed by any language that knows how to work with the syndication standard. There are a number of syndication formats in use, one of the more popular ones being RSS 2.0. About Syndication in .Net Microsoft introduced System.ServiceModel.Syndication namespace in .Net Framework 3.5, before that there was not any b...