如何正确声明EnumChildWindows，GCHandle，EnumWindow，EnumWindowProc及其参数？ [英] How to declare EnumChildWindows, GCHandle, EnumWindow, EnumWindowProc with theirs parameters correctly?

问题描述

大家好！



我在EnumChildWindows，GCHandle，EnumWindow，EnumWindowProc中遇到参数问题。我想从应用程序中获取句柄，findWindowEx仅在第一个子窗口上工作，我想要第二个句柄而不是第一个。



我不知道他们的参数是什么，除了句柄（hwnd）。请帮我正确申报/填写。



以下是pinvoke.net的代码：

Hi Everyone!

I have a problem with parameters in EnumChildWindows, GCHandle, EnumWindow, EnumWindowProc. I wanna get the handles from an application and the findWindowEx works only on the first child window and I wanna get the second handle not the first.

I don't know what their parameters are except the handle (hwnd). Please help me to correctly declare / fill them.

Here is a code from pinvoke.net:

using System.Runtime.InteropServices;

[DllImport("user32.dll")]
[return: MarshalAs(UnmanagedType.Bool)]
public static extern bool EnumChildWindows(IntPtr window, EnumWindowProc callback, IntPtr i);

/// <summary>
/// Returns a list of child windows
/// </summary>
/// <param name="parent">Parent of the windows to return</param>
/// <returns>List of child windows</returns>

public static List<IntPtr> GetChildWindows(IntPtr parent)
{
    List<IntPtr> result = new List<IntPtr>();
    GCHandle listHandle = GCHandle.Alloc(result);
    try
    {
        EnumWindowProc childProc = new EnumWindowProc(EnumWindow);
        EnumChildWindows(parent, childProc, GCHandle.ToIntPtr(listHandle));
    }
    finally
    {
        if (listHandle.IsAllocated)
            listHandle.Free();
    }
    return result;
}

/// <summary>
/// Callback method to be used when enumerating windows.
/// </summary>
/// <param name="handle">Handle of the next window</param>
/// <param name="pointer">Pointer to a GCHandle that holds a reference to the list to fill</param>
/// <returns>True to continue the enumeration, false to bail</returns>
private static bool EnumWindow(IntPtr handle, IntPtr pointer)
{
    GCHandle gch = GCHandle.FromIntPtr(pointer);
    List<IntPtr> list = gch.Target as List<IntPtr>;
    if (list == null)
    {
        throw new InvalidCastException("GCHandle Target could not be cast as List<IntPtr>");
    }
    list.Add(handle);
    //  You can modify this to check to see if you want to cancel the operation, then return a null here
    return true;
}

/// <summary>
/// Delegate for the EnumChildWindows method
/// </summary>
/// <param name="hWnd">Window handle</param>
/// <param name="parameter">Caller-defined variable; we use it for a pointer to our list</param>
/// <returns>True to continue enumerating, false to bail.</returns>
public delegate bool EnumWindowProc(IntPtr hWnd, IntPtr parameter);

推荐答案

您需要的信息都在文档中。从 https://msdn.microsoft.com/开始en-us / library / windows / desktop / ms633497％28v = vs.85％29.aspx [ ^ ]。

The information you want is all in the documentation. Start at https://msdn.microsoft.com/en-us/library/windows/desktop/ms633497%28v=vs.85%29.aspx[^].

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