如何防止鍵盤寫入其他應用程序

Question

我正在使用簡單的Hookup記錄BarcodeScanner中的鍵，這是通過USB作爲鍵盤進行連接的鍵。我使用的這個例子，我在網上找到：

using System.Windows.Forms; 

namespace RawInput 
{ 
public partial class Form1 : Form 
{ 
    InputDevice id; 
    int NumberOfKeyboards; 

    public Form1() 
    { 
     InitializeComponent(); 

     // Create a new InputDevice object, get the number of 
     // keyboards, and register the method which will handle the 
     // InputDevice KeyPressed event 
     id = new InputDevice(Handle); 
     NumberOfKeyboards = id.EnumerateDevices(); 
     id.KeyPressed += new InputDevice.DeviceEventHandler(m_KeyPressed); 
    } 

    // The WndProc is overridden to allow InputDevice to intercept 
    // messages to the window and thus catch WM_INPUT messages 
    protected override void WndProc(ref Message message) 
    { 
     if(id != null) 
     { 
      id.ProcessMessage(message); 
     } 
     base.WndProc(ref message); 
    } 

    private void m_KeyPressed(object sender, InputDevice.KeyControlEventArgs e) 
    { 
     //Replace() is just a cosmetic fix to stop ampersands turning into underlines 
     lbHandle.Text = e.Keyboard.deviceHandle.ToString(); 
     lbType.Text = e.Keyboard.deviceType; 
     lbName.Text = e.Keyboard.deviceName.Replace("&", "&&"); 
     lbDescription.Text = e.Keyboard.Name;   
     lbKey.Text = e.Keyboard.key.ToString(); 
     lbNumKeyboards.Text = NumberOfKeyboards.ToString(); 
     lbVKey.Text = e.Keyboard.vKey; 
    } 

    private void btnClose_Click(object sender, System.EventArgs e) 
    { 
     this.Close(); 
    } 

} 
} 

的問題是，條形碼掃描器寫入任何應用程序處於焦點。運行時，是否可以將此設備的所有數據重定向到我的應用程序？

Answer 1

如果您的設備已安裝爲鍵盤（而不是非鍵盤HMI設備），這並不容易，因爲鍵盤和鼠標受操作系統限制。

This answer說明了您可能如何解決此限制。

祝你好運！