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DatabindExprRegex Class

Provides a regular expression to parse an ASP.NET data-binding expression.

Namespace: System.Web.RegularExpressions
Assembly: System.Web.RegularExpressions (in system.web.regularexpressions.dll)

public class DatabindExprRegex extends Regex implements ISerializable
public class DatabindExprRegex extends Regex implements ISerializable
Not applicable.

The DatabindExprRegex class provides a regular expression to parse an ASP.NET data-binding expression (<%#%>).


The System.Web.RegularExpressions classes are meant to be used by the .NET Framework to parse ASP.NET pages and are not always practical for general applications. For example, many of these classes match only the beginning of a string.

The following code example demonstrates the DatabindExprRegex class.

' This example demonstrates the System.Web.RegularExpressions 
' constructors. 
' Each regular expression class is used to match an appropriate 
' string. Note that the System.Web.RegularExpressions classes 
' are intended for internal use and are not always practical for 
' general applications. In particular, many of these regular 
' expressions match only the beginning of a string.

Imports System
Imports System.Text.RegularExpressions
Imports System.Web.RegularExpressions

Class Sample
    Public Shared Sub Main() 
        Dim str1A As String = "<%-- COMMENT BLOCK --%> Initial pattern."
        Dim str1B As String = "Embedded pattern. <%-- COMMENT BLOCK --%>"
        Dim str02 As String = "<% CODE BLOCK %>"
        Dim str03 As String = "<%= EXPRESSION BLOCK %>"
        Dim str04 As String = "<%# DATA BINDING EXPRESSION %>"
        Dim str05 As String = "<%@ DIRECTIVE %>"
        Dim str06 As String = "</END_TAG> xyz"
        Dim str07 As String = "GREATER THAN >"
        Dim str08 As String = "< LESS THAN"
        ' Include directive.
        Dim str09 As String = "<!-- #include file=""filename.ext"" -->"
        ' runat="server" attribute.
        Dim str10 As String = "<script runat=""server"" language=""codelanguage"" src=""pathname"">"
        Dim str11 As String = "<% SERVER TAG %>"
        Dim str12 As String = "abc defg hi jkl <%-- TEXTREGEX --%> mno pqr"
        Dim str13 As String = "<%# DATA BINDING %>"
        Dim str14 As String = "<asp:TAG> ... </asp:TAG>"
        Dim str15 As String = "<%@ SIMPLE DIRECTIVE %>"
        ' -------------------------------------------------------------------
        ' Demonstrate that a pattern must occur at the beginning of the 
        ' string. That is, the entire string is not scanned for the pattern.
        ' -------------------------------------------------------------------
        Dim cr As New CommentRegex()
        Display(cr, str1A)
        Display(cr, str1B)
        ' -------------------------------------------------------------------
        Display(New AspCodeRegex(), str02)
        Display(New AspExprRegex(), str03)
        Display(New DatabindExprRegex(), str04)
        Display(New DirectiveRegex(), str05)
        Display(New EndTagRegex(), str06)
        Display(New GTRegex(), str07)
        Display(New LTRegex(), str08)
        Display(New IncludeRegex(), str09)
        Display(New RunatServerRegex(), str10)
        Display(New ServerTagsRegex(), str11)
        Display(New TextRegex(), str12)
        Display(New DataBindRegex(), str13)
        Display(New TagRegex(), str14)
        Display(New SimpleDirectiveRegex(), str15)
    End Sub 'Main
    Protected Shared Sub Display(ByVal r As Regex, ByVal s As String) 
        Console.WriteLine("Input: ""{0}""", s)
        Dim m As Match = r.Match(s)
        If m.Success Then
            Console.WriteLine("Match: ""{0}""", m.Value)
            Console.WriteLine("There is no match.")
        End If
    End Sub 'Display
End Class 'Sample
'This code example produces the following results:
'Input: "<%-- COMMENT BLOCK --%> Initial pattern."
'Match: "<%-- COMMENT BLOCK --%>"
'Input: "Embedded pattern. <%-- COMMENT BLOCK --%>"
'There is no match.
'Input: "<% CODE BLOCK %>"
'Match: "<% CODE BLOCK %>"
'Input: "<%= EXPRESSION BLOCK %>"
'Match: "<%= EXPRESSION BLOCK %>"
'Input: "<%@ DIRECTIVE %>"
'Match: "<%@ DIRECTIVE %>"
'Input: "</END_TAG> xyz"
'Match: "</END_TAG>"
'Input: "GREATER THAN >"
'Match: " >"
'Input: "< LESS THAN"
'Match: "< "
'Input: "<!-- #include file="filename.ext" -->"
'Match: "<!-- #include file="filename.ext" -->"
'Input: "<script runat="server" language="codelanguage" src="pathname">"
'Match: "runat="server"
'Input: "<% SERVER TAG %>"
'Match: "<% SERVER TAG %>"
'Input: "abc defg hi jkl <%-- TEXTREGEX --%> mno pqr"
'Match: "abc defg hi jkl "
'Input: "<%# DATA BINDING %>"
'Match: "<%# DATA BINDING %>"
'Input: "<asp:TAG> ... </asp:TAG>"
'Match: "<asp:TAG>"
'Input: "<%@ SIMPLE DIRECTIVE %>"
'Match: "<%@ SIMPLE DIRECTIVE %>"


Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

Windows 98, Windows Server 2000 SP4, Windows Millennium Edition, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.

.NET Framework

Supported in: 3.0, 2.0, 1.1, 1.0

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