StagingAreaInputItem.cs source code in C# .NET

Source code for the .NET framework in C#

                        

Code:

/ 4.0 / 4.0 / untmp / DEVDIV_TFS / Dev10 / Releases / RTMRel / wpf / src / Core / CSharp / System / Windows / Input / StagingAreaInputItem.cs / 1407647 / StagingAreaInputItem.cs

                            using System; 
using System.Collections;
using System.Security.Permissions;
using System.Security;
 
namespace System.Windows.Input
{ 
    ///  
    ///     This class encapsulates an input event while it is being
    ///     processed by the input manager. 
    /// 
    /// 
    ///     This class just provides the dictionary-based storage for
    ///     all of the listeners of the various input manager events. 
    /// 
    public class StagingAreaInputItem 
    { 
        // Only we can make these.
        internal StagingAreaInputItem(bool isMarker) 
        {
            _isMarker = isMarker;
        }
 
        // For performace reasons, we try to reuse these event args.
        // Allow an existing item to be promoted by keeping the existing dictionary. 
        internal void Reset(InputEventArgs input, StagingAreaInputItem promote) 
        {
            _input = input; 

            if(promote != null && promote._dictionary != null)
            {
                // 
                _dictionary = (Hashtable) promote._dictionary.Clone();
            } 
            else 
            {
                if(_dictionary != null) 
                {
                    _dictionary.Clear();
                }
                else 
                {
                    _dictionary = new Hashtable(); 
                } 
            }
        } 

        /// 
        ///     Returns the input event.
        ///  
        /// 
        ///     Callers must have UIPermission(PermissionState.Unrestricted) to call this API. 
        ///  
        /// 
        ///     Defense In Depth - even if this leaks out, we demand here. 
        ///     Critical - Performs a Link Demand. The reason these methods are marked critical
        ///                is that security transparent code should not be responsible for verifying
        ///                the security of an operation, and therefore should not be protected from partial
        ///                trust callers with LinkDemands. 
        /// 
        public InputEventArgs Input 
        { 
            [SecurityCritical]
            [UIPermissionAttribute(SecurityAction.LinkDemand,Unrestricted=true)] 
            get {return _input;}
        }

        ///  
        ///     Provides storage for arbitrary data needed during the
        ///     processing of this input event. 
        ///  
        /// 
        ///     An arbitrary key for the data.  This cannot be null. 
        /// 
        /// 
        ///     The data previously set for this key, or null.
        ///  
        public object GetData(object key)
        { 
            return _dictionary[key]; 
        }
 
        /// 
        ///     Provides storage for arbitrary data needed during the
        ///     processing of this input event.
        ///  
        /// 
        ///     An arbitrary key for the data.  This cannot be null. 
        ///  
        /// 
        ///     The data to set for this key.  This can be null. 
        /// 
        /// 
        ///     Callers must have UIPermission(PermissionState.Unrestricted) to call this API.
        ///  
        /// 
        ///     Defense In Depth - even if this leaks out, we demand here. 
        ///     Critical - Performs a Link Demand. The reason these methods are marked critical 
        ///                is that security transparent code should not be responsible for verifying
        ///                the security of an operation, and therefore should not be protected from partial 
        ///                trust callers with LinkDemands.
        /// 
        [SecurityCritical]
        [UIPermissionAttribute(SecurityAction.LinkDemand,Unrestricted=true)] 
        public void SetData(object key, object value)
        { 
            _dictionary[key] = value; 
        }
 
        internal bool IsMarker {get {return _isMarker;}}

        private bool _isMarker;
        private InputEventArgs _input; 
        private Hashtable _dictionary;
    } 
} 


// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
// Copyright (c) Microsoft Corporation. All rights reserved.
                        

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