SecurityElement Klasse

Definition

public ref class SecurityElement sealed

[System.Serializable]
public sealed class SecurityElement

[System.Serializable]
[System.Runtime.InteropServices.ComVisible(true)]
public sealed class SecurityElement

public sealed class SecurityElement

[<System.Serializable>]
type SecurityElement = class

[<System.Serializable>]
[<System.Runtime.InteropServices.ComVisible(true)>]
type SecurityElement = class

type SecurityElement = class

Public NotInheritable Class SecurityElement

Vererbung

Object

SecurityElement

Attribute

SerializableAttribute ComVisibleAttribute

Beispiele

Das folgende Beispiel zeigt die Verwendung von Membern der SecurityElement Klasse.

using System;
using System.Security;
using System.Collections;

class SecurityElementMembers
{
    [STAThread]
    static void Main(string[] args)
    {
        SecurityElement xmlRootElement =
            new SecurityElement("RootTag", "XML security tree");

        AddAttribute(xmlRootElement,"creationdate",DateTime.Now.ToString());
        AddChildElement(xmlRootElement,"destroytime",
            DateTime.Now.AddSeconds(1.0).ToString());

        SecurityElement windowsRoleElement =
            new SecurityElement("WindowsMembership.WindowsRole");

        windowsRoleElement.AddAttribute("version","1.00");

        // Add a child element and a creationdate attribute.
        AddChildElement(windowsRoleElement,"BabyElement",
            "This is a child element");
        AddAttribute(windowsRoleElement,"creationdate",
            DateTime.Now.ToString());

        xmlRootElement.AddChild(windowsRoleElement);

        CompareAttributes(xmlRootElement, "creationdate");
        ConvertToHashTable(xmlRootElement);

        DisplaySummary(xmlRootElement);

        // Determine if the security element is too old to keep.
        xmlRootElement = DestroyTree(xmlRootElement);
        if (xmlRootElement != null)
        {
            string elementInXml = xmlRootElement.ToString();
            Console.WriteLine(elementInXml);
        }

        Console.WriteLine("This sample completed successfully; " +
            "press Enter to exit.");
        Console.ReadLine();
    }

    // Add an attribute to the specified security element.
    private static SecurityElement AddAttribute(
        SecurityElement xmlElement,
        string attributeName,
        string attributeValue)
    {
        if (xmlElement != null)
        {
            // Verify that the attribute name and value are valid XML formats.
            if (SecurityElement.IsValidAttributeName(attributeName) &&
                SecurityElement.IsValidAttributeValue(attributeValue))
            {
                // Add the attribute to the security element.
                xmlElement.AddAttribute(attributeName, attributeValue);
            }
        }
        return xmlElement;
    }

    // Add a child element to the specified security element.
    private static SecurityElement AddChildElement(
        SecurityElement parentElement,
        string tagName,
        string tagText)
    {
        if (parentElement != null)
        {
            // Ensure that the tag text is in valid XML format.
            if (!SecurityElement.IsValidText(tagText))
            {
                // Replace invalid text with valid XML text
                // to enforce proper XML formatting.
                tagText = SecurityElement.Escape(tagText);
            }

            // Determine whether the tag is in valid XML format.
            if (SecurityElement.IsValidTag(tagName))
            {
                SecurityElement childElement;
                childElement = parentElement.SearchForChildByTag(tagName);

                if (childElement != null)
                {
                    String elementText;
                    elementText = parentElement.SearchForTextOfTag(tagName);

                    if (!elementText.Equals(tagText))
                    {
                        // Add child element to the parent security element.
                        parentElement.AddChild(
                            new SecurityElement(tagName, tagText));
                    }
                }
                else
                {
                    // Add child element to the parent security element.
                    parentElement.AddChild(
                        new SecurityElement(tagName, tagText));
                }
            }
        }
        return parentElement;
    }

    // Create and display a summary sentence
    // about the specified security element.
    private static void DisplaySummary(SecurityElement xmlElement)
    {
        // Retrieve tag name for the security element.
        string xmlTreeName = xmlElement.Tag.ToString();

        // Retrieve tag text for the security element.
        string xmlTreeDescription = xmlElement.Text;

        // Retrieve value of the creationdate attribute.
        string xmlCreationDate = xmlElement.Attribute("creationdate");

        // Retrieve the number of children under the security element.
        string childrenCount = xmlElement.Children.Count.ToString();

        string outputMessage = "The security XML tree named " + xmlTreeName;
        outputMessage += "(" + xmlTreeDescription + ")";
        outputMessage += " was created on " + xmlCreationDate + " and ";
        outputMessage += "contains " + childrenCount + " child elements.";

        Console.WriteLine(outputMessage);
    }

    // Compare the first two occurrences of an attribute
    // in the specified security element.
    private static void CompareAttributes(
        SecurityElement xmlElement, string attributeName)
    {
        // Create a hash table containing the security element's attributes.
        Hashtable attributeKeys = xmlElement.Attributes;
        string attributeValue = attributeKeys[attributeName].ToString();

        foreach(SecurityElement xmlChild in xmlElement.Children)
        {
            if (attributeValue.Equals(xmlChild.Attribute(attributeName)))
            {
                // The security elements were created at the exact same time.
            }
        }
    }

    // Convert the contents of the specified security element
    // to hash codes stored in a hash table.
    private static void ConvertToHashTable(SecurityElement xmlElement)
    {
        // Create a hash table to hold hash codes of the security elements.
        Hashtable xmlAsHash = new Hashtable();
        int rootIndex = xmlElement.GetHashCode();
        xmlAsHash.Add(rootIndex, "root");

        int parentNum = 0;

        foreach(SecurityElement xmlParent in xmlElement.Children)
        {
            parentNum++;
            xmlAsHash.Add(xmlParent.GetHashCode(), "parent" + parentNum);
            if ((xmlParent.Children != null) &&
                (xmlParent.Children.Count > 0))
            {
                int childNum = 0;
                foreach(SecurityElement xmlChild in xmlParent.Children)
                {
                    childNum++;
                    xmlAsHash.Add(xmlChild.GetHashCode(), "child" + childNum);
                }
            }
        }
    }

    // Delete the specified security element if the current time is past
    // the time stored in the destroytime tag.
    private static SecurityElement DestroyTree(SecurityElement xmlElement)
    {
        SecurityElement localXmlElement = xmlElement;
        SecurityElement destroyElement =
            localXmlElement.SearchForChildByTag("destroytime");

        // Verify that a destroytime tag exists.
        if (localXmlElement.SearchForChildByTag("destroytime") != null)
        {
            // Retrieve the destroytime text to get the time
            // the tree can be destroyed.
            string storedDestroyTime =
                localXmlElement.SearchForTextOfTag("destroytime");

            DateTime destroyTime = DateTime.Parse(storedDestroyTime);
            if (DateTime.Now > destroyTime)
            {
                localXmlElement = null;
                Console.WriteLine("The XML security tree has been deleted.");
            }
        }

        // Verify that xmlElement is of type SecurityElement.
        if (xmlElement.GetType().Equals(
            typeof(System.Security.SecurityElement)))
        {
            // Determine whether the localXmlElement object
            // differs from xmlElement.
            if (xmlElement.Equals(localXmlElement))
            {
                // Verify that the tags, attributes and children of the
                // two security elements are identical.
                if (xmlElement.Equal(localXmlElement))
                {
                    // Return the original security element.
                    return xmlElement;
                }
            }
        }

        // Return the modified security element.
        return localXmlElement;
    }
}
//
// This sample produces the following output:
//
// The security XML tree named RootTag(XML security tree)
// was created on 2/23/2004 1:23:00 PM and contains 2 child elements.
//<RootTag creationdate="2/23/2004 1:23:00 PM">XML security tree
//   <destroytime>2/23/2004 1:23:01 PM</destroytime>
//   <WindowsMembership.WindowsRole version="1.00"
//                                  creationdate="2/23/2004 1:23:00 PM">
//      <BabyElement>This is a child element.</BabyElement>
//
//This sample completed successfully; press Exit to continue.

Imports System.Security
Imports System.Collections



Class SecurityElementMembers

    <STAThread()> _
    Shared Sub Main(ByVal args() As String)
        Dim xmlRootElement As New SecurityElement("RootTag", "XML security tree")
        AddAttribute(xmlRootElement, "creationdate", DateTime.Now.ToString())
        AddChildElement(xmlRootElement, "destroytime", DateTime.Now.AddSeconds(1.0).ToString())

        Dim windowsRoleElement As New SecurityElement("WindowsMembership.WindowsRole")
        windowsRoleElement.AddAttribute("version", "1.00")
        ' Add a child element and a creationdate attribute.
        AddChildElement(windowsRoleElement, "BabyElement", "This is a child element")
        AddAttribute(windowsRoleElement, "creationdate", DateTime.Now.ToString())

        xmlRootElement.AddChild(windowsRoleElement)
        CompareAttributes(xmlRootElement, "creationdate")
        ConvertToHashTable(xmlRootElement)

        DisplaySummary(xmlRootElement)

        ' Determine if the security element is too old to keep.
        xmlRootElement = DestroyTree(xmlRootElement)
        If Not (xmlRootElement Is Nothing) Then
            Dim elementInXml As String = xmlRootElement.ToString()
            Console.WriteLine(elementInXml)
        End If

        Console.WriteLine("This sample completed successfully; " + "press Enter to exit.")
        Console.ReadLine()

    End Sub


    ' Add an attribute to the specified security element.
    Private Shared Function AddAttribute(ByVal xmlElement As SecurityElement, ByVal attributeName As String, ByVal attributeValue As String) As SecurityElement
        If Not (xmlElement Is Nothing) Then
            ' Verify that the attribute name and value are valid XML formats.
            If SecurityElement.IsValidAttributeName(attributeName) AndAlso SecurityElement.IsValidAttributeValue(attributeValue) Then
                ' Add the attribute to the security element.
                xmlElement.AddAttribute(attributeName, attributeValue)
            End If
        End If
        Return xmlElement

    End Function 'AddAttribute


    ' Add a child element to the specified security element.
    Private Shared Function AddChildElement(ByVal parentElement As SecurityElement, ByVal tagName As String, ByVal tagText As String) As SecurityElement
        If Not (parentElement Is Nothing) Then
            ' Ensure that the tag text is in valid XML format.
            If Not SecurityElement.IsValidText(tagText) Then
                ' Replace invalid text with valid XML text 
                ' to enforce proper XML formatting.
                tagText = SecurityElement.Escape(tagText)
            End If

            ' Determine whether the tag is in valid XML format.
            If SecurityElement.IsValidTag(tagName) Then
                Dim childElement As SecurityElement
                childElement = parentElement.SearchForChildByTag(tagName)
                If Not (childElement Is Nothing) Then
                    Dim elementText As String
                    elementText = parentElement.SearchForTextOfTag(tagName)
                    If Not elementText.Equals(tagText) Then
                        ' Add child element to the parent security element.
                        parentElement.AddChild(New SecurityElement(tagName, tagText))
                    End If
                Else
                    ' Add child element to the parent security element.
                    parentElement.AddChild(New SecurityElement(tagName, tagText))
                End If
            End If
        End If
        Return parentElement

    End Function 'AddChildElement


    ' Create and display a summary sentence 
    ' about the specified security element.
    Private Shared Sub DisplaySummary(ByVal xmlElement As SecurityElement)
        ' Retrieve tag name for the security element.
        Dim xmlTreeName As String = xmlElement.Tag.ToString()
        ' Retrieve tag text for the security element.
        Dim xmlTreeDescription As String = xmlElement.Text
        ' Retrieve value of the creationdate attribute.
        Dim xmlCreationDate As String = xmlElement.Attribute("creationdate")
        ' Retrieve the number of children under the security element.
        Dim childrenCount As String = xmlElement.Children.Count.ToString()
        Dim outputMessage As String = "The security XML tree named " + xmlTreeName
        outputMessage += "(" + xmlTreeDescription + ")"
        outputMessage += " was created on " + xmlCreationDate + " and "
        outputMessage += "contains " + childrenCount + " child elements."

        Console.WriteLine(outputMessage)

    End Sub


    ' Compare the first two occurrences of an attribute 
    ' in the specified security element.
    Private Shared Sub CompareAttributes(ByVal xmlElement As SecurityElement, ByVal attributeName As String)
        ' Create a hash table containing the security element's attributes.
        Dim attributeKeys As Hashtable = xmlElement.Attributes
        Dim attributeValue As String = attributeKeys(attributeName).ToString()
        Dim xmlChild As SecurityElement
        For Each xmlChild In xmlElement.Children
            If attributeValue.Equals(xmlChild.Attribute(attributeName)) Then
            End If
        Next xmlChild
        ' The security elements were created at the exact same time.
    End Sub


    ' Convert the contents of the specified security element 
    ' to hash codes stored in a hash table.
    Private Shared Sub ConvertToHashTable(ByVal xmlElement As SecurityElement)
        ' Create a hash table to hold hash codes of the security elements.
        Dim xmlAsHash As New Hashtable()
        Dim rootIndex As Integer = xmlElement.GetHashCode()
        xmlAsHash.Add(rootIndex, "root")
        Dim parentNum As Integer = 0

        Dim xmlParent As SecurityElement
        For Each xmlParent In xmlElement.Children
            parentNum += 1
            xmlAsHash.Add(xmlParent.GetHashCode(), "parent" + parentNum.ToString())
            If Not (xmlParent.Children Is Nothing) AndAlso xmlParent.Children.Count > 0 Then
                Dim childNum As Integer = 0
                Dim xmlChild As SecurityElement
                For Each xmlChild In xmlParent.Children
                    childNum += 1
                    xmlAsHash.Add(xmlChild.GetHashCode(), "child" + childNum.ToString())
                Next xmlChild
            End If
        Next xmlParent

    End Sub


    ' Delete the specified security element if the current time is past
    ' the time stored in the destroytime tag.
    Private Shared Function DestroyTree(ByVal xmlElement As SecurityElement) As SecurityElement
        Dim localXmlElement As SecurityElement = xmlElement
        Dim destroyElement As SecurityElement = localXmlElement.SearchForChildByTag("destroytime")

        ' Verify that a destroytime tag exists.
        If Not (localXmlElement.SearchForChildByTag("destroytime") Is Nothing) Then
            ' Retrieve the destroytime text to get the time 
            ' the tree can be destroyed.
            Dim storedDestroyTime As String = localXmlElement.SearchForTextOfTag("destroytime")
            Dim destroyTime As DateTime = DateTime.Parse(storedDestroyTime)
            If DateTime.Now > destroyTime Then
                localXmlElement = Nothing
                Console.WriteLine("The XML security tree has been deleted.")
            End If
        End If

        ' Verify that xmlElement is of type SecurityElement.
        If xmlElement.GetType().Equals(GetType(System.Security.SecurityElement)) Then
            ' Determine whether the localXmlElement object 
            ' differs from xmlElement.
            If xmlElement.Equals(localXmlElement) Then
                ' Verify that the tags, attributes and children of the
                ' two security elements are identical.
                If xmlElement.Equal(localXmlElement) Then
                    ' Return the original security element.
                    Return xmlElement
                End If
            End If
        End If

        ' Return the modified security element.
        Return localXmlElement

    End Function 'DestroyTree
End Class
'
' This sample produces the following output:
' 
' The security XML tree named RootTag(XML security tree) 
' was created on 2/23/2004 1:23:00 PM and contains 2 child elements.
'<RootTag creationdate="2/23/2004 1:23:00 PM">XML security tree
'   <destroytime>2/23/2004 1:23:01 PM</destroytime>
'   <WindowsMembership.WindowsRole version="1.00"
'                                  creationdate="2/23/2004 1:23:00 PM">
'      <BabyElement>This is a child element.</BabyElement>
'
'This sample completed successfully; press Exit to continue.

Hinweise

Diese Klasse ist eine einfache Implementierung eines einfachen XML-Objektmodells für die Verwendung im Sicherheitssystem und nicht für die Verwendung als allgemeines XML-Objektmodell. In dieser Dokumentation wird ein grundlegendes Wissen über XML vorausgesetzt.

Das einfache XML-Objektmodell für ein Element besteht aus den folgenden Teilen:

• Das Tag ist der Elementname.

• Die Attribute sind null oder mehr Name/Wert-Attributpaare für das Element.

• Die untergeordneten Elemente sind null oder mehr Elemente, die in <tag> und </tag>.

Es wird dringend empfohlen, dass attributbasierte XML-Darstellung verwendet wird, um Sicherheitselemente und deren Werte auszudrücken. Dies bedeutet, dass Eigenschaften eines Elements als Attribute ausgedrückt werden und Eigenschaftswerte als Attributwerte ausgedrückt werden. Vermeiden Sie das Schachteln von Text in Tags. Für jede <tag>text</tag> Darstellung des Typs <tag value="text"/> ist in der Regel eine Darstellung verfügbar. Die Verwendung dieser attributbasierten XML-Darstellung erhöht die Lesbarkeit und ermöglicht eine einfache WMI-Portabilität der resultierenden XML-Serialisierung.

Ein Attributname muss ein Zeichen oder länger sein und darf nicht sein null. Wenn eine elementbasierte Wertdarstellung verwendet wird, werden Elemente mit einer Textzeichenfolge, die in der <tag/> Form dargestellt wirdnull, verwendet. Andernfalls wird Text durch die <tag> Und-Token </tag> getrennt. Beide Formulare können mit Attributen kombiniert werden, die angezeigt werden, wenn vorhanden.

Bei tags, attributen und text of elements, if present, wird immer die Groß-/Kleinschreibung beachtet. Das XML-Formular enthält ggf. Anführungszeichen und Escapezeichen. Zeichenfolgenwerte, die Zeichen enthalten, die für die Verwendung in XML ungültig sind, führen zu einem ArgumentException. Diese Regeln gelten für alle Eigenschaften und Methoden.