SecurityPermission Class
Describes a set of security permissions applied to code. This class cannot be inherited.
Assembly: mscorlib (in mscorlib.dll)
This permission uses the SecurityPermissionFlag enumeration. The values for this enumeration can be found in its documentation.
The following code example demonstrates the behavior of the SecurityPermission methods.
The example is intended to show how the methods perform if you execute the methods from your code. In general, the methods of permission classes are used by the security infrastructure; they are not typically used in applications.
For an example showing the use of the SecurityPermission class to demand permission for a specific SecurityPermissionFlag enumeration value, see the SecurityPermission(SecurityPermissionFlag) constructor.
Imports System Imports System.Security Imports System.Security.Permissions Imports Microsoft.VisualBasic <Assembly: CLSCompliant(True)> Public Class SecurityPermissionDemo ' IsSubsetOf determines whether the current permission is a subset of the specified permission. Private Function IsSubsetOfDemo() As Boolean Dim returnValue As Boolean = True Dim Security1, Security2 As SecurityPermissionFlag Dim SecurityPerm1, SecurityPerm2 As SecurityPermission Dim SecurityGen1 As New SecurityGenerator() Dim SecurityGen2 As New SecurityGenerator() SecurityGen1.ResetIndex() While SecurityGen1.GetSecurityFlag(Security1) SecurityPerm1 = New SecurityPermission(Security1) SecurityGen2.ResetIndex() Console.WriteLine("********************************************************" & ControlChars.Lf) While SecurityGen2.GetSecurityFlag(Security2) SecurityPerm2 = New SecurityPermission(Security2) Try If SecurityPerm1.IsSubsetOf(SecurityPerm2) Then Console.WriteLine((SecurityPerm1.Flags.ToString().ToString() _ & " is a subset of " & SecurityPerm2.Flags.ToString())) Else Console.WriteLine((SecurityPerm1.Flags.ToString() & " is not a subset of " _ & SecurityPerm2.Flags.ToString())) End If Catch e As Exception Console.WriteLine(("An exception was thrown for subset :" & SecurityPerm1.ToString() _ & ControlChars.Lf & SecurityPerm2.ToString() & ControlChars.Lf & e.ToString())) returnValue = False End Try End While End While Return returnValue End Function 'IsSubsetOfDemo ' Union creates a new permission that is the union of the current permission and ' the specified permission. Private Function UnionDemo() As Boolean Dim returnValue As Boolean = True Dim Security1, Security2 As SecurityPermissionFlag Dim SecurityPerm1, SecurityPerm2 As SecurityPermission Dim SecurityPerm3 As IPermission Dim SecurityGen1 As New SecurityGenerator() Dim SecurityGen2 As New SecurityGenerator() SecurityGen1.ResetIndex() While SecurityGen1.GetSecurityFlag(Security1) SecurityPerm1 = New SecurityPermission(Security1) Console.WriteLine("**********************************************************" & ControlChars.Lf) SecurityGen2.ResetIndex() While SecurityGen2.GetSecurityFlag(Security2) SecurityPerm2 = New SecurityPermission(Security2) SecurityPerm3 = CType(SecurityPerm1.Union(SecurityPerm2), SecurityPermission) SecurityPerm3 = SecurityPerm1.Union(SecurityPerm2) If SecurityPerm3 Is Nothing Then Console.WriteLine(("The union of " & Security1 & " and " & Security2 & " is null.")) Else Console.WriteLine(("The union of " & SecurityPerm1.Flags.ToString() _ & " and " & SecurityPerm2.Flags.ToString() & " = " & CType(SecurityPerm3, SecurityPermission).Flags.ToString().ToString())) End If End While End While Return returnValue End Function 'UnionDemo ' Intersect creates and returns a new permission that is the intersection of the current ' permission and the permission specified. Private Function IntersectDemo() As Boolean Dim returnValue As Boolean = True Dim Security1, Security2 As SecurityPermissionFlag Dim SecurityPerm1, SecurityPerm2, SecurityPerm3 As SecurityPermission Dim SecurityGen1 As New SecurityGenerator() Dim SecurityGen2 As New SecurityGenerator() SecurityGen1.ResetIndex() While SecurityGen1.GetSecurityFlag(Security1) SecurityPerm1 = New SecurityPermission(Security1) Console.WriteLine("**********************************************************" & ControlChars.Lf) SecurityGen2.ResetIndex() While SecurityGen2.GetSecurityFlag(Security2) SecurityPerm2 = New SecurityPermission(Security2) SecurityPerm3 = CType(SecurityPerm1.Intersect(SecurityPerm2), SecurityPermission) If Not (SecurityPerm3 Is Nothing) Then Console.WriteLine(("The intersection of " & Security1.ToString() & " and " _ & Security2.ToString() & " = " _ & CType(SecurityPerm3, SecurityPermission).Flags.ToString().ToString())) Else Console.WriteLine(("The intersection of " & Security1.ToString() & " and " _ & Security2.ToString() & " is null.")) End If End While End While Return returnValue End Function 'IntersectDemo 'Copy creates and returns an identical copy of the current permission. Private Function CopyDemo() As Boolean Dim returnValue As Boolean = True Dim Security1 As SecurityPermissionFlag Dim SecurityPerm1, SecurityPerm2 As SecurityPermission Dim SecurityGen1 As New SecurityGenerator() Dim SecurityGen2 As New SecurityGenerator() SecurityGen1.ResetIndex() While SecurityGen1.GetSecurityFlag(Security1) SecurityPerm1 = New SecurityPermission(Security1) SecurityGen2.ResetIndex() Console.WriteLine("********************************************************" & ControlChars.Lf) Try SecurityPerm2 = CType(SecurityPerm1.Copy(), SecurityPermission) Console.WriteLine(("Result of copy = " & SecurityPerm2.ToString())) Catch e As Exception Console.WriteLine(("Copy failed :" & SecurityPerm1.ToString() & e.ToString())) Continue While End Try End While Return returnValue End Function 'CopyDemo ' ToXml creates an XML encoding of the permission and its current state; ' FromXml reconstructs a permission with the specified state from the XML encoding. Private Function ToFromXmlDemo() As Boolean Dim returnValue As Boolean = True Dim Security1 As SecurityPermissionFlag Dim SecurityPerm1, SecurityPerm2 As SecurityPermission Dim SecurityGen1 As New SecurityGenerator() Dim SecurityGen2 As New SecurityGenerator() SecurityGen1.ResetIndex() While SecurityGen1.GetSecurityFlag(Security1) SecurityPerm1 = New SecurityPermission(Security1) Console.WriteLine("********************************************************" & ControlChars.Lf) SecurityGen2.ResetIndex() Try SecurityPerm2 = New SecurityPermission(PermissionState.None) SecurityPerm2.FromXml(SecurityPerm1.ToXml()) Console.WriteLine(("Result of ToFromXml = " & SecurityPerm2.ToString())) Catch e As Exception Console.WriteLine(("ToFromXml failed :" & SecurityPerm1.ToString() & e.ToString())) Continue While End Try End While Return returnValue End Function 'ToFromXmlDemo ' Invoke all demos. Public Function runDemo() As Boolean Dim returnCode As Boolean = True Dim tempReturnCode As Boolean ' Call the IsSubsetOf demo. tempReturnCode = IsSubsetOfDemo() If tempReturnCode Then Console.Out.WriteLine("IsSubsetOf demo completed successfully.") Else Console.Out.WriteLine("IsSubsetOf demo failed.") End If returnCode = tempReturnCode AndAlso returnCode ' Call the Union demo. tempReturnCode = UnionDemo() If tempReturnCode Then Console.Out.WriteLine("Union demo completed successfully.") Else Console.Out.WriteLine("Union demo failed.") End If returnCode = tempReturnCode AndAlso returnCode ' Call the Intersect demo. tempReturnCode = IntersectDemo() If tempReturnCode Then Console.Out.WriteLine("Intersect demo completed successfully.") Else Console.Out.WriteLine("Intersect demo failed.") End If returnCode = tempReturnCode AndAlso returnCode ' Call the Copy demo. tempReturnCode = CopyDemo() If tempReturnCode Then Console.Out.WriteLine("Copy demo completed successfully.") Else Console.Out.WriteLine("Copy demo failed.") End If returnCode = tempReturnCode AndAlso returnCode ' Call the ToFromXml demo. tempReturnCode = ToFromXmlDemo() If tempReturnCode Then Console.Out.WriteLine("ToFromXml demo completed successfully.") Else Console.Out.WriteLine("ToFromXml demo failed.") End If returnCode = tempReturnCode AndAlso returnCode Return returnCode End Function 'runDemo ' Test harness. Public Overloads Shared Sub Main(ByVal args() As [String]) Try Dim democase As New SecurityPermissionDemo() Dim returnCode As Boolean = democase.runDemo() If returnCode Then Console.Out.WriteLine("SecurityPermission demo completed successfully.") Console.Out.WriteLine("Press the Enter key to exit.") Dim consoleInput As String = Console.ReadLine() System.Environment.ExitCode = 100 Else Console.Out.WriteLine("SecurityPermission demo failed.") Console.Out.WriteLine("Press the Enter key to exit.") Dim consoleInput As String = Console.ReadLine() System.Environment.ExitCode = 101 End If Catch e As Exception Console.Out.WriteLine("SecurityPermission demo failed.") Console.WriteLine(e.ToString()) Console.Out.WriteLine("Press the Enter key to exit.") Dim consoleInput As String = Console.ReadLine() System.Environment.ExitCode = 101 End Try End Sub 'Main End Class 'SecurityPermissionDemo ' This class generates SecurityPermission objects. Friend Class SecurityGenerator Private mySecurity As SecurityPermissionFlag() = {SecurityPermissionFlag.AllFlags, _ SecurityPermissionFlag.Assertion Or SecurityPermissionFlag.ControlAppDomain, _ SecurityPermissionFlag.ControlAppDomain, _ SecurityPermissionFlag.ControlDomainPolicy Or SecurityPermissionFlag.ControlEvidence, _ SecurityPermissionFlag.ControlEvidence, _ SecurityPermissionFlag.ControlPolicy Or SecurityPermissionFlag.ControlPrincipal, _ SecurityPermissionFlag.ControlPrincipal, _ SecurityPermissionFlag.ControlThread, _ SecurityPermissionFlag.Execution, _ SecurityPermissionFlag.Infrastructure, _ SecurityPermissionFlag.NoFlags, _ SecurityPermissionFlag.RemotingConfiguration Or SecurityPermissionFlag.SerializationFormatter, _ SecurityPermissionFlag.SerializationFormatter, _ SecurityPermissionFlag.SkipVerification, _ SecurityPermissionFlag.UnmanagedCode} Private reflectionIndex As Integer = 0 Public Sub New() ResetIndex() End Sub 'New Public Sub ResetIndex() reflectionIndex = 0 End Sub 'ResetIndex ' GetSecurityFlag creates a SecurityPermission object. Public Function GetSecurityFlag(ByRef Security As SecurityPermissionFlag) As Boolean If reflectionIndex >= mySecurity.Length Then Security = SecurityPermissionFlag.NoFlags reflectionIndex &= 1 Return False End If Security = mySecurity(reflectionIndex) reflectionIndex = reflectionIndex + 1 Return True End Function End Class
Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98
The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.