Question

我之前在这个论坛上寻找帮助解决这个问题。基本上我是从类中动态创建一个表单，我希望在屏幕上没有标题栏可拖动。我遇到的代码是：

public const int WM_NCLBUTTONDOWN = 0xA1;
public const int HT_CAPTION = 0x2;
[System.Runtime.InteropServices.DllImport("user32.dll")]
public static extern int SendMessage(IntPtr hWnd, int Msg, int wParam, int lParam);
[System.Runtime.InteropServices.DllImport("user32.dll")]
public static extern bool ReleaseCapture();

private void window_MouseDown(object sender, System.Windows.Forms.MouseEventArgs e)
{
    if (e.Button == MouseButtons.Left)
    {
        ReleaseCapture();
        SendMessage(Handle, WM_NCLBUTTONDOWN, HT_CAPTION, 0);
    }
}

然而，当我尝试编译时，我收到以下错误：

错误1名称＆＃39;处理＆＃39;在当前不存在上下文C：\ Users \ xxxxxx \ Documents \ Visual Studio 2013 \ Projects \ practiceProgressBar2 \ practiceProgressBar2 \ Notifications.cs 109 29 practiceProgressBar2

有没有人知道我做错了什么，因为我整天都在处理这个问题

Answer 1

变化：

SendMessage(Handle, WM_NCLBUTTONDOWN, HT_CAPTION, 0);

要：

SendMessage(((Form)sender).Handle, WM_NCLBUTTONDOWN, HT_CAPTION, 0);

如果您有其他控件，例如Labels，指向同一个处理程序，那么您可以使用它来代替拖动标签时拖动它：

SendMessage(((Control)sender).FindForm().Handle, WM_NCLBUTTONDOWN, HT_CAPTION, 0);

Answer 2

请尝试改写表单的WndProc方法。

public const int HTCAPTION = 0x2;
public const int WM_NCHITTEST = 0x84;
public const int HTCLIENT = 1;

protected override void WndProc(ref Message m)
{
    base.WndProc(ref m);

    if (m.Msg == WM_NCHITTEST)
    {
        if (m.Result.ToInt32() == HTCLIENT)
            m.Result = (IntPtr)HTCAPTION;
    }
}

没有头衔的可动形式

2 个答案: