There are few lines of plugin and its explanation.
[DllImport(“User32.dll”)] public static extern int SendMessage(IntPtr hWnd, int uMsg, int wParam, string lParam);
[DllImport(“User32.dll”)] public static extern int SendMessage(IntPtr hWnd, int uMsg, int wParam, int lParam);
[DllImport(“user32.dll”)] public static extern IntPtr GetActiveWindow();
[DllImport(“user32.dll”)] public static extern IntPtr GetForegroundWindow();
[DllImport(“user32.dll”)] public static extern bool SetActiveWindow(IntPtr hWnd);
[DllImport(“user32.dll”)] public static extern bool SetForegroundWindow(IntPtr hWnd);
[DllImport(“user32.dll”)] public static extern bool ShowWindow(IntPtr hWnd, int nCmdShow);
[DllImport(“user32.dll”, SetLastError = true)] private static extern int GetWindowThreadProcessId(IntPtr hWnd, out int lpdwProcessId);
[DllImport(“user32.dll”)]
Explanation
This code snippet is written in C# and uses Platform Invocation Services (P/Invoke) to call functions from the User32.dll library, which is a dynamic link library (DLL) containing various functions related to user interface interactions in Windows.
Let’s break down the code and explain each part:
1. **`[DllImport(“User32.dll”)]`**: This attribute is used to indicate that the method is implemented in the User32.dll library. It allows C# code to call functions from native libraries.
2. **`public static extern int SendMessage(IntPtr hWnd, int uMsg, int wParam, string lParam);`**: This line declares a C# method named `SendMessage` that corresponds to the `SendMessage` function in User32.dll. This function is used to send a message to the specified window.
3. **`public static extern int SendMessage(IntPtr hWnd, int uMsg, int wParam, int lParam);`**: Similar to the previous line, this declares another version of the `SendMessage` method, but with different parameter types. It’s overloaded to support sending messages with an integer parameter instead of a string.
4. **`[DllImport(“user32.dll”)] public static extern IntPtr GetActiveWindow();`**: Declares a C# method named `GetActiveWindow` that corresponds to the `GetActiveWindow` function in User32.dll. This function retrieves a handle to the active window.
5. **`[DllImport(“user32.dll”)] public static extern IntPtr GetForegroundWindow();`**: Declares a C# method named `GetForegroundWindow` that corresponds to the `GetForegroundWindow` function in User32.dll. This function retrieves a handle to the foreground window.
6. **`[DllImport(“user32.dll”)] public static extern bool SetActiveWindow(IntPtr hWnd);`**: Declares a C# method named `SetActiveWindow` that corresponds to the `SetActiveWindow` function in User32.dll. This function sets the active window.
7. **`[DllImport(“user32.dll”)] public static extern bool SetForegroundWindow(IntPtr hWnd);`**: Declares a C# method named `SetForegroundWindow` that corresponds to the `SetForegroundWindow` function in User32.dll. This function brings the specified window to the foreground.
8. **`[DllImport(“user32.dll”)] public static extern bool ShowWindow(IntPtr hWnd, int nCmdShow);`**: Declares a C# method named `ShowWindow` that corresponds to the `ShowWindow` function in User32.dll. This function sets the specified window’s show state.
9. **`[DllImport(“user32.dll”, SetLastError = true)] private static extern int GetWindowThreadProcessId(IntPtr hWnd, out int lpdwProcessId);`**: Declares a C# method named `GetWindowThreadProcessId` that corresponds to the `GetWindowThreadProcessId` function in User32.dll. This function retrieves the identifier of the thread that created the specified window and optionally the identifier of the process that created the window.
This code is essentially a C# wrapper around various User32.dll functions, making it easier to interact with window management and messaging in a Windows environment.
Please let me know if you want to know more about and if you want develop Encompass plugin or custom form
