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ContextStack Class

Provides a stack object that can be used by a serializer to make information available to nested serializers.

Namespace:  System.ComponentModel.Design.Serialization
Assembly:  System (in System.dll)

[PermissionSetAttribute(SecurityAction.LinkDemand, Name = "FullTrust")]
[HostProtectionAttribute(SecurityAction.LinkDemand, SharedState = true)]
public sealed class ContextStack

NoteNote:

The HostProtectionAttribute attribute applied to this type or member has the following Resources property value: SharedState. The HostProtectionAttribute does not affect desktop applications (which are typically started by double-clicking an icon, typing a command, or entering a URL in a browser). For more information, see the HostProtectionAttribute class or SQL Server Programming and Host Protection Attributes.

Some serializers require information about the context of an object to correctly persist their state. The ContextStack class enables a serializer to set data about the context of an object that is being serialized to a stack where another serializer can access it. The value of the Context property is provided by an IDesignerSerializationManager to share information of use to some serializers.

A context stack is useful because the process of serializing a design document can be deeply nested, and objects at each level of nesting may require context information to correctly persist the state of the object. A serializer can set a context object to the stack before invoking a nested serializer. Each object set to the stack should be removed by the serializer that set it after a call to a nested serializer returns.

Typically, the objects on the stack contain information about the context of the current object that is being serialized. A parent serializer adds context information to the stack about the next object to be serialized, calls an appropriate serializer and, when the serializer finishes executing on the object, removes the context information from the stack. It is up to the implementation of each serializer to determine what objects get pushed on this stack.

As an example, an object with a property named Enabled has a data type of Boolean. If a serializer writes this value to a data stream, it might need to include the context or type of property it is writing. The serializer does not have this information, however, because it is only instructed to write the Boolean value. To provide this information to the serializer, the parent serializer can push a PropertyDescriptor that points to the Enabled property on the context stack.

The following code example demonstrates using a ContextStack to push and then remove 10 values.

using System;
using System.ComponentModel;
using System.ComponentModel.Design;
using System.ComponentModel.Design.Serialization;
using System.Windows.Forms;

namespace ContextStackExample
{
    class ContextStackExample
    {
        [STAThread]
        static void Main(string[] args)
        {            
            // Create a ContextStack.
            ContextStack stack = new ContextStack();

            // Push ten items on to the stack and output the value of each. 
            for( int number = 0; number < 10; number ++ )
            {
                Console.WriteLine( "Value pushed to stack: "+number.ToString() );
                stack.Push( number );
            }

            // Pop each item off the stack.
            object item = null;
            while( (item = stack.Pop()) != null )
                Console.WriteLine( "Value popped from stack: "+item.ToString() );
        }
    }
}

System.Object
  System.ComponentModel.Design.Serialization.ContextStack

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 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.

.NET Framework

Supported in: 3.5, 3.0, 2.0, 1.1, 1.0

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