WPF技巧汇总

资源文件获取方式

比如我在Resources中添加了一个App.jpg文件，那么如果我想获得这个文件可以这样获得：

           StreamResourceInfo info = System.Windows.Application.GetResourceStream(new Uri("/项目名字;component/Resources/App.jpg", UriKind.Relative));

          System.Drawing.Image.FromStream(info.Stream);

有一点需要注意的是图片的生成操作要设置为Resource方式。

 

全局热键的设置

添加如下类：

    /// <summary>
    /// 直接构造类实例即可注册
    /// 自动完成注销 ,热键会随着程序结束自动解除,不会写入注册表
    /// 注意注册时会抛出异常
    /// </summary>
    class HotKey
    {
        #region Member

        int KeyId ;         //热键编号
        IntPtr Handle ;     //窗体句柄
        Window window ;     //热键所在窗体
        uint Controlkey ;   //热键控制键
        uint Key ;          //热键主键

        public delegate void OnHotkeyEventHandeler();     //热键事件委托
        public event OnHotkeyEventHandeler OnHotKey=null;   //热键事件    

        static Hashtable KeyPair = new Hashtable();         //热键哈希表

        private const int WM_HOTKEY = 0x0312;       // 热键消息编号

        public enum KeyFlags    //控制键编码
        {
            MOD_ALT = 0x1,
            MOD_CONTROL = 0x2,
            MOD_SHIFT = 0x4,
            MOD_WIN = 0x8
        }        

        #endregion

        /// <summary>
        /// 构造函数
        /// </summary>
        /// <param name="win">注册窗体</param>
        /// <param name="control">控制键</param>
        /// <param name="key">主键</param>
        public HotKey(Window win, HotKey.KeyFlags control, Keys key)
        {
            Handle = new WindowInteropHelper(win).Handle;
            window=win;
            Controlkey = (uint)control;
            Key = (uint)key;
            KeyId=(int)Controlkey+(int)Key*10;
            if (HotKey.KeyPair.ContainsKey(KeyId))
            {
                throw new Exception("热键已经被注册!");
            }

            //注册热键
            if(false == HotKey.RegisterHotKey(Handle, KeyId, Controlkey, Key))
            {
                throw new Exception("热键注册失败!");
            }
            if(HotKey.KeyPair.Count==0){
                //消息挂钩只能连接一次!!
                if(false == InstallHotKeyHook(this))
                {
                    throw new Exception("消息挂钩连接失败!");
                }
            }

            //添加这个热键索引
            HotKey.KeyPair.Add(KeyId, this);
            
        }

        #region core

        [System.Runtime.InteropServices.DllImport("user32")]
        private static extern bool RegisterHotKey(IntPtr hWnd, int id, uint controlKey, uint virtualKey);
                
        [System.Runtime.InteropServices.DllImport("user32")]
        private static extern bool UnregisterHotKey(IntPtr hWnd, int id);

        //安装热键处理挂钩
        static private bool InstallHotKeyHook(HotKey hk)
        {
            if (hk.window == null || hk.Handle==IntPtr.Zero)
                return false;

            //获得消息源
            System.Windows.Interop.HwndSource source = System.Windows.Interop.HwndSource.FromHwnd(hk.Handle);
            if (source==null)  return false;

            //挂接事件
            source.AddHook(HotKey.HotKeyHook);
            return true;
        }

        //热键处理过程
        static private IntPtr HotKeyHook(IntPtr hwnd, int msg, IntPtr wParam, IntPtr lParam, ref bool handled)
        {
            if (msg == WM_HOTKEY)
            {
                HotKey hk = (HotKey)HotKey.KeyPair[(int)wParam];
                if (hk.OnHotKey != null)   hk.OnHotKey();                    
            }    
            return IntPtr.Zero;
        }

        //析构函数,解除热键
        ~HotKey()
        {
           HotKey.UnregisterHotKey(Handle, KeyId);
        }

        #endregion
    }

使用方法：在load事件中使用（不要在构造函数中使用，因为此时句柄还没有创建好）

 

        void Window1_Loaded(object sender, RoutedEventArgs e)
        {
            HotKey key = new HotKey(this, HotKey.KeyFlags.MOD_CONTROL, Keys.T);
            key.OnHotKey += new HotKey.OnHotkeyEventHandeler(key_OnHotKey);
        }