这里有一个小示例,展示了如何在另一个进程中关闭窗口。创建一个新的 Windows 窗体项目,在其中添加两个窗体并在第一个窗体上添加两个按钮并将该代码放在 Form1 中:
public partial class Form1 : Form
{
delegate bool EnumWindowsProc(IntPtr Hwnd, IntPtr lParam);
[DllImport("user32", SetLastError = true)]
[return: MarshalAs(UnmanagedType.Bool)]
private extern static bool EnumThreadWindows(int threadId, EnumWindowsProc callback, IntPtr lParam);
[DllImport("user32", SetLastError = true)]
[return: MarshalAs(UnmanagedType.Bool)]
static extern bool EnumChildWindows(IntPtr hwndParent, EnumWindowsProc lpEnumFunc, IntPtr lParam);
[DllImport("user32", SetLastError = true, CharSet = CharSet.Auto)]
private extern static int GetWindowText(IntPtr hWnd, StringBuilder text, int maxCount);
[DllImport("user32.dll", CharSet = CharSet.Auto)]
static extern IntPtr SendMessage(IntPtr hWnd, UInt32 Msg, IntPtr wParam, IntPtr lParam);
private const int WM_CLOSE = 0x10;
public Form1()
{
InitializeComponent();
button1.Click += button1_Click;
button2.Click += button2_Click;
}
private void button1_Click(object sender, EventArgs e)
{
var frm = new Form2();
frm.Show(this);
}
private void button2_Click(object sender, EventArgs e)
{
Process[] processes = Process.GetProcessesByName("FindWindowSample");
foreach (Process p in processes)
{
var handle = FindWindowInProcess(p, x => x == "Form2");
if (handle != IntPtr.Zero)
{
SendMessage(handle, WM_CLOSE, IntPtr.Zero, IntPtr.Zero);
}
}
}
public static IntPtr FindWindowInProcess(Process process, Func<string, bool> compareTitle)
{
IntPtr windowHandle = IntPtr.Zero;
foreach (ProcessThread t in process.Threads)
{
windowHandle = FindWindowInThread(t.Id, compareTitle);
if (windowHandle != IntPtr.Zero)
{
break;
}
}
return windowHandle;
}
private static IntPtr FindWindowInThread(int threadId, Func<string, bool> compareTitle)
{
IntPtr windowHandle = IntPtr.Zero;
EnumThreadWindows(threadId, (hWnd, lParam) =>
{
StringBuilder text = new StringBuilder(200);
GetWindowText(hWnd, text, 200);
if (compareTitle(text.ToString()))
{
windowHandle = hWnd;
return false;
}
return true;
}, IntPtr.Zero);
return windowHandle;
}
}
编译然后运行应用程序的两个实例。在第一个上单击 Button1 以显示 Form2。在第二个实例上单击 Button2 以从第一个实例关闭 Form2。