KeyEventArgs.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 / KeyEventArgs.cs / 1305600 / KeyEventArgs.cs
                        

                        
                             
using System;
using System.Security;
using MS.Internal;
using MS.Internal.PresentationCore;                        // SecurityHelper 

namespace System.Windows.Input 
{ 
    /// 
    ///     The KeyEventArgs class contains information about key states. 
    /// 
    /// 
    public class KeyEventArgs : KeyboardEventArgs
    { 
        /// 
        ///     Constructs an instance of the KeyEventArgs class. 
        ///  
        /// 
        ///     The logical keyboard device associated with this event. 
        /// 
        /// 
        ///     The input source that provided this input.
        ///  
        /// 
        ///     The time when the input occured. 
        ///  
        /// 
        ///     The key referenced by the event. 
        /// 
        ///
        ///     Critical - accepts PresentationSource.
        /// 
        [SecurityCritical]
        public KeyEventArgs(KeyboardDevice keyboard, PresentationSource inputSource, int timestamp, Key key) : base(keyboard, timestamp) 
        { 
            if (inputSource == null)
                throw new ArgumentNullException("inputSource"); 

            if (!Keyboard.IsValidKey(key))
                throw new System.ComponentModel.InvalidEnumArgumentException("key", (int)key, typeof(Key));
 
            _inputSource = inputSource;
 
            _realKey = key; 
            _isRepeat = false;
 
            // Start out assuming that this is just a normal key.
            MarkNormal();
        }
 
        /// 
        ///     The input source that provided this input. 
        ///  
        /// 
        ///     Callers must have UIPermission(PermissionState.Unrestricted) to call this API. 
        /// 
        ///
        ///     Critical - hands out _inputSource via UnsafeInputSource call.
        ///     PublicOK - there is a demand. 
        ///
        public PresentationSource InputSource 
        { 
            [SecurityCritical ]
            get 
            {
                SecurityHelper.DemandUnrestrictedUIPermission();

                return UnsafeInputSource; 
            }
        } 
 
        /// 
        ///     The Key referenced by the event, if the key is not being 
        ///     handled specially.
        /// 
        public Key Key
        { 
            get {return _key;}
        } 
 
        /// 
        ///     The original key, as opposed to , which might 
        ///     have been changed (e.g. by MarkTextInput).
        /// 
        /// 
        /// Note:  This should remain internal.  When a processor obfuscates the key, 
        /// such as changing characters to Key.TextInput, we're deliberately trying to
        /// hide it and make it hard to find.  But internally we'd like an easy way to find 
        /// it.  So we have this internal, but it must remain internal. 
        /// 
        internal Key RealKey 
        {
            get { return _realKey; }
        }
 
        /// 
        ///     The Key referenced by the event, if the key is going to be 
        ///     processed by an IME. 
        /// 
        public Key ImeProcessedKey 
        {
            get { return (_key == Key.ImeProcessed) ? _realKey : Key.None;}
        }
 
        /// 
        ///     The Key referenced by the event, if the key is going to be 
        ///     processed by an system. 
        /// 
        public Key SystemKey 
        {
            get { return (_key == Key.System) ? _realKey : Key.None;}
        }
 
        /// 
        ///     The Key referenced by the event, if the the key is going to 
        ///     be processed by Win32 Dead Char System. 
        /// 
        public Key DeadCharProcessedKey 
        {
            get { return (_key == Key.DeadCharProcessed) ? _realKey : Key.None; }
        }
 
        /// 
        ///     The state of the key referenced by the event. 
        ///  
        public KeyStates KeyStates
        { 
            get {return this.KeyboardDevice.GetKeyStates(_realKey);}
        }

        ///  
        ///     Whether the key pressed is a repeated key or not.
        ///  
        public bool IsRepeat 
        {
            get {return _isRepeat;} 
        }

        /// 
        ///     Whether or not the key referenced by the event is down. 
        /// 
        ///  
        public bool IsDown 
        {
            get {return this.KeyboardDevice.IsKeyDown(_realKey);} 
        }

        /// 
        ///     Whether or not the key referenced by the event is up. 
        /// 
        ///  
        public bool IsUp 
        {
            get {return this.KeyboardDevice.IsKeyUp(_realKey);} 
        }

        /// 
        ///     Whether or not the key referenced by the event is toggled. 
        /// 
        ///  
        public bool IsToggled 
        {
            get {return this.KeyboardDevice.IsKeyToggled(_realKey);} 
        }

        /// 
        ///     The mechanism used to call the type-specific handler on the 
        ///     target.
        ///  
        ///  
        ///     The generic handler to call in a type-specific way.
        ///  
        /// 
        ///     The target to call the handler on.
        /// 
        ///  
        protected override void InvokeEventHandler(Delegate genericHandler, object genericTarget)
        { 
            KeyEventHandler handler = (KeyEventHandler) genericHandler; 

            handler(genericTarget, this); 
        }

        internal void SetRepeat( bool newRepeatState )
        { 
            _isRepeat = newRepeatState;
        } 
 
        internal void MarkNormal()
        { 
            _key = _realKey;
        }

        internal void MarkSystem() 
        {
            _key = Key.System; 
        } 

        internal void MarkImeProcessed() 
        {
            _key = Key.ImeProcessed;
        }
 
        internal void MarkDeadCharProcessed()
        { 
            _key = Key.DeadCharProcessed; 
        }
        /// 
        /// Critical - hands out _inputSource.
        ///
        internal PresentationSource UnsafeInputSource
        { 
            [SecurityCritical]
            get 
            { 
                return _inputSource;
            } 
        }

        internal int ScanCode
        { 
            get {return _scanCode;}
            set {_scanCode = value;} 
        } 

        internal bool IsExtendedKey 
        {
            get {return _isExtendedKey;}
            set {_isExtendedKey = value;}
        } 

 
        private Key _realKey; 
        private Key _key;
 
        ///
        ///     Critical - PresentationSource required elevations to create it.
        ///
        [SecurityCritical] 
        private PresentationSource _inputSource;
 
        private bool _isRepeat; 
        private int _scanCode;
        private bool _isExtendedKey; 

    }
}
 

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

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