C# 发生缓冲区溢出

Question

A buffer overrun has occurred in MyApp.exe which has corrupted the program's internal state.

我已经尝试了一些事情，但无法弄清楚是什么导致了上述 1/50 的调用，可能是一些显而易见的事情，但有很多东西需要猜测。

[DllImport("user32.dll")]
public static extern IntPtr GetTopWindow(IntPtr hWnd);

[DllImport("user32.dll")]
public static extern uint GetWindowThreadProcessId(IntPtr hWnd, out UInt32 pid);

[DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]
public static extern int GetWindowText(IntPtr hWnd, StringBuilder lpString, int nMaxCount);

[DllImport("user32.dll", SetLastError = true)]
public static extern IntPtr GetWindow(IntPtr hWnd, uint uCmd);

public static IntPtr GetProcessWindow(int processId)
{
    UInt32 pid = 0;
    UInt32 dwThreadId = 0;
    StringBuilder a = new StringBuilder();
    IntPtr hwnd = GetTopWindow(IntPtr.Zero);

    while(hwnd != null)
    {
        dwThreadId = GetWindowThreadProcessId(hwnd, out pid);
        GetWindowText(hwnd, a, 256);
        String name = a.ToString();
        if(pid == processId && name.Contains("[Window Name]"))
            return hwnd;
        hwnd = GetWindow(hwnd, 2);
    }

    return IntPtr.Zero;
}

提前致谢。

Answer 1

您没有在 StringBuilder 中预先分配缓冲区。

这一行:

StringBuilder a = new StringBuilder();

应该是:

StringBuilder a = new StringBuilder(256);