Simulating Key Press C

Question

I want to simulate F5 key press in my C  program  When IE is open  I want to be able refresh my website automatically  How can I do that

User · Answer

The easiest way to send   simulate  KeyStrokes to any window is to use the SendKeys Send method of  NET Framework   Checkout this very intuitive MSDN article http   msdn microsoft com en-us library system windows forms sendkeys aspx    Particularly for your case  if your browser window is in focus  sending F5 would just involve the following line of code   SendKeys Send   F5

User · Answer

Another alternative to simulating a F5 key press would be to simply host the WebBrowser control in the Window Forms application  You use the WebBrowser Navigate method to load your web page and then use a standard Timer and on each tick of the timer you just re-Navigate to the url which will reload the page

User · Answer

You can use the Win32 API FindWindow or FindWindowEx to find the window handle of the open browser and then just call SendMessage with WM KEYDOWN   Typically it s easiest just to pass the window caption to FindWindowEx and have it find the associated window handle for you   If you are starting the browser process yourself via a Process process object then you can use process MainWindowHandle instead of calling FindWindowEx   Spy   is a very useful tool when you want to start working with other windows   It basically allows you to learn another program s hierarchy of UI elements   You can also monitor all of the messages that go into the window you re monitoring  I have more info in this thread   The F5 keystroke has this virtual key code   const int VK F5   0x74    The p invoke signature for FindWindowEx in C  is     DllImport  user32 dll   SetLastError   true   static extern IntPtr FindWindowEx IntPtr hwndParent  IntPtr hwndChildAfter  string lpszClass  string lpszWindow     You can p invoke  bring in  the Win32 API SendMessage like this    DllImport  user32 dll   CharSet   CharSet Auto   static extern IntPtr SendMessage IntPtr hWnd  UInt32 Msg  IntPtr wParam  IntPtr lParam     So to recap  you call FindWindowEx directly from your C  code after having the above code somewhere inside your class   FindWindowEx will return a window handle  Then once you have the window handle  you can send any keystroke s  to the window  or call many other Win32 API calls on the window handle   Or even find a child window by using another call to FindWindowEx   For example you could select the edit control of the browser even and then change it s text    If all else goes wrong and you think you re sending the right key to the window  you can use spy   to see what messages are sent to the window when you manually set focus to the browser and manually press F5

User · Answer

Instead of forcing an F5 keypress when you re just trying to get the page to postback  you can call a postback based on a JS event  even mousemove or timer tick if you want it to fire all the time    Use the code at http   weblogs asp net mnolton archive 2003 06 04 8260 aspx as a reference

User · Answer

Simple one  add before Main       DllImport  USER32 DLL   CharSet   CharSet Unicode   public static extern IntPtr FindWindow string lpClassName  string lpWindowName    DllImport  USER32 DLL    public static extern bool SetForegroundWindow IntPtr hWnd     Code inside Main Method   string className    IEFrame   string windowName    New Tab - Windows Internet Explorer   IntPtr IE   FindWindow className  windowName   if  IE    IntPtr Zero       return    SetForegroundWindow IE   InputSimulator SimulateKeyPress VirtualKeyCode F5     Note    Add InputSimulator as reference  To download Click here To find Class  amp  Window name  use WinSpy    To download Click here

User · Answer

Here s an example     static class Program        DllImport  user32 dll        public static extern int SetForegroundWindow IntPtr hWnd         STAThread      static void Main                 while true                        Process    processes   Process GetProcessesByName  iexplore                 foreach Process proc in processes                                SetForegroundWindow proc MainWindowHandle                   SendKeys SendWait   F5                                Thread Sleep 5000                       a better one    less anoying     static class Program       const UInt32 WM KEYDOWN   0x0100      const int VK F5   0x74        DllImport  user32 dll        static extern bool PostMessage IntPtr hWnd  UInt32 Msg  int wParam  int lParam         STAThread      static void Main                 while true                        Process    processes   Process GetProcessesByName  iexplore                 foreach Process proc in processes                  PostMessage proc MainWindowHandle  WM KEYDOWN  VK F5  0                Thread Sleep 5000

User · Answer

Use mouse event or keybd event  They say not to use them anymore but you don t have to find the window at all    using System  using System Runtime InteropServices   public class SimulatePCControl     DllImport  user32 dll   CharSet   CharSet Auto  CallingConvention   CallingConvention StdCall   public static extern void keybd event uint bVk  uint bScan  uint dwFlags  uint dwExtraInfo    private const int VK LEFT   0x25   public static void LeftArrow         keybd event VK LEFT  0  0  0          Virtual Key Codes are here for this one  http   www kbdedit com manual low level vk list html  Also for mouse   using System Runtime InteropServices  using UnityEngine   public class SimulateMouseClick    DllImport  user32 dll   CharSet   CharSet Auto  CallingConvention   CallingConvention StdCall   public static extern void mouse event uint dwFlags  uint dx  uint dy  uint cButtons  uint dwExtraInfo     Mouse actions private const int MOUSEEVENTF LEFTDOWN   0x02  private const int MOUSEEVENTF LEFTUP   0x04  private const int MOUSEEVENTF RIGHTDOWN   0x08  private const int MOUSEEVENTF RIGHTUP   0x10   public static void Click           Call the imported function with the cursor s current position     uint X    uint 0      uint Y    uint 0      mouse event MOUSEEVENTF LEFTDOWN   MOUSEEVENTF LEFTUP  X  Y  0  0       Debug LogError  SIMULATED A MOUSE CLICK JUST NOW               other code needed for the application

User · Answer

Easy  short and no need window focus   Also here a usefull list of Virtual Key Codes           DllImport  user32 dll            public static extern IntPtr FindWindow string lpClassName  string lpWindowName             DllImport  user32 dll            static extern bool PostMessage IntPtr hWnd  UInt32 Msg  int wParam  int lParam            private void button1 Click object sender  EventArgs e                        const int WM SYSKEYDOWN   0x0104              const int VK F5   0x74               IntPtr WindowToFind   FindWindow null   Google - Mozilla Firefox                 PostMessage WindowToFind  WM SYSKEYDOWN  VK F5  0

[c#] Simulating Key Press C#

Examples related to c#