我的屏幕保護程序正在停止屏幕暫停，但我不想它

Question

我在.Net 4.0中做了一個屏幕保護程序。它基本上只是移動圖像中的位並使用它來顯示它。在計時器上失效並覆蓋onPaint事件。

到目前爲止，它工作得很好 - 但是 - 我注意到它有一個問題。

它正在停止監視器在暫停超時後掛起。由於我安裝了它，我的顯示器現在保持24/7。

事情是，我沒有做任何事情來明確停止省電功能 - 而且我確定我的電腦的省電設置已設置（它們是）。所以我選擇了另一個屏幕保護程序，以確保設置仍然有效。監視器在超時後暫停。

那麼我需要做些什麼才能與電源管理打好關係？我在谷歌搜索這個答案，我發現的一切是如何阻止電源管理，我沒有明確阻止它！我只是想在暫停時間允許暫停。

Answer 1

我能夠讓我的程序「玩得很好」。我不知道它爲什麼會起作用，原始代碼沒有，但是這不僅有效 - 它實際上使得程序更加「節能」，因爲它在屏幕暫停後不進行計算，從而減少了CPU週期。總之，我預覽了WndProc消息，並尋找顯示器正在被暫停的消息，一旦收到，我停止重畫直到它恢復（可以恢復並使屏保仍然有效）。

代碼更改：

// Field Definitions 
    /// <summary> 
    /// Constants that relate to the WndProc messages we wish to intercept and evaluate. 
    /// </summary> 
    [System.Diagnostics.CodeAnalysis.SuppressMessage("StyleCop.CSharp.NamingRules", "SA1310:FieldNamesMustNotContainUnderscore", Justification = "Standard practice to use this naming style for Win32 API Constants.")] 
    private const int WM_SYSCOMMAND = 0x0112, SC_MONITORPOWER = 0xF170; 

    /// <summary> 
    /// Gets or sets whether we are suspended. Should coincide with whether the display is turned on or not. 
    /// </summary> 
    private bool isSuspended = false; 


    // New overridden method 
    /// <summary> 
    /// Intercepts WndProc messages. We are looking for the screen suspend activity. From it, we will return that we are able to suspend and we ourselves will suspend. 
    /// </summary> 
    /// <param name="m">Message to be checked.</param> 
    protected override void WndProc(ref Message m) 
    { 
     if (m.Msg == WM_SYSCOMMAND) 
     { 
      // The 0x000F bits are used to indicate the specific state and must be ignored to see if this is a monitor power event. 
      if ((m.WParam.ToInt32() & 0xFFF0) == SC_MONITORPOWER) 
      { 
       switch (m.WParam.ToInt32() & 0x000F) 
       { 
        case -1: 
         // Display powering on - resume operation 
#if DEBUG 
         System.Diagnostics.Debug.WriteLine("Display powered on."); 
#endif 
         this.isSuspended = false; 
         break; 
        case 0: 
        case 1: 
        case 2: 
         // Display being powered off - suspend operation 
#if DEBUG 
         System.Diagnostics.Debug.WriteLine("Display suspended"); 
#endif 
         this.isSuspended = true; 
         break; 
        default: 
#if DEBUG 
         System.Diagnostics.Debug.WriteLine(string.Format("Unknown power state: {0}", (m.WParam.ToInt32() & 0x000F).ToString("0"))); 
#endif 
         // Assuming that unknown values mean to power off. This is a WAG. 
         this.isSuspended = true; 
         break; 
       } 
      } 
     } 

     base.WndProc(ref m); 
    } 


    // Change to my refreshing timer. 
    /// <summary> 
    /// Called when the refresh timer ticks. This invalidates the form, forcing it to be redrawn, which creates a framerate for us. 
    /// </summary> 
    /// <param name="sender">Who called this method.</param> 
    /// <param name="e">Event Arguments.</param> 
    private void RefreshTimer_Tick(object sender, EventArgs e) 
    { 
     if (this.isSuspended) 
     { 
      // Program is in suspended mode, so don't do anything this update. 
      return; 
     } 

     // Program is not suspended, so invalidate the client area so it can be painted again. 
     this.Invalidate(); 
    } 

此更改停止時暫停被稱爲所有重繪（並停止GDI +計算），並使其後，屏幕保護程序「行爲」與電源管理設置。

Answer 2

你是否有意無意地陷入WM_SYSCOMMAND的0xF170（SC_MONITORPOWER）子命令？