GetWindowRect 返回 0

Question

我正在尝试查找我正在打开的新进程的 window 大小，但它返回 0 的高度和宽度。这是我的代码：

[DllImport("user32.dll")]
[return: MarshalAs(UnmanagedType.Bool)]
static extern bool GetWindowRect(IntPtr hWnd, ref RECT rect);

[StructLayout(LayoutKind.Sequential)]
public struct RECT
{
    public int Left;        // x position of upper-left corner
    public int Top;         // y position of upper-left corner
    public int Right;       // x position of lower-right corner
    public int Bottom;      // y position of lower-right corner
}

static void Main(string[] args)
{
    Process process = new Process();
    process.StartInfo.FileName = @"C:\Program Files (x86)\FirstClass\fcc32.exe";
    //C:\Program Files (x86)\FirstClass\fcc32.exe
    process.Start();

    Console.WriteLine(process.HandleCount);
    IntPtr hWnd = process.MainWindowHandle;

    RECT rect = new RECT();
    process.WaitForInputIdle();
    GetWindowRect(hWnd, ref rect);
    int width = rect.Right - rect.Left;
    int height = rect.Bottom - rect.Top;

    Console.WriteLine("Height: " + height + ", Width: " + width);
    Console.ReadLine();
}

Answer 1

签名错误应该是：

[DllImport("user32.dll", SetLastError=true)]
static extern bool GetWindowRect(IntPtr hwnd, out RECT lpRect);

相应地更改调用代码：

RECT rect;
process.WaitForInputIdle();
GetWindowRect(hWnd, out rect);

Answer 2

谢谢大家的回答，但实际问题是我在做

IntPtr hWnd = process.MainWindowHandle;

在进程window之前实际上有机会打开。

GetWindowRect 返回 0

GetWindowRect returning 0

.net

c#

dll

window