在 .NET Compact Framework 中触发按钮单击

Question

假设我有一个包含许多 Button 和 PictureBox 控件的面板。每个控件都有一个关联的 Click 事件。这是一个触摸屏应用程序，因此用户的点击可能有点不精确（或者触摸屏校准可能不完美）。所以，我想处理面板上的点击事件，然后如果点击靠近按钮/图片，则以编程方式调用按钮或图片框的点击事件。

许多其他答案建议使用“PerformClick”事件，但 Compact Framework 不支持此操作。有什么选择吗？我的代码：

private void pnlButtons_Click(object sender, EventArgs e)
{
    Point ptClick = Control.MousePosition;
    foreach (Control cntrl in pnlButtons.Controls)
    {
        // Make sure the control is visible!
        if (cntrl.Visible)
        {
            // Click close to control?
            if ((ptClick.X > (cntrl.Left - 5)) &&
                (ptClick.X < (cntrl.Right + 5)) &&
                (ptClick.Y > (cntrl.Top - 5)) &&
                (ptClick.Y < (cntrl.Bottom + 5)))
            {
                // Click Button or PictureBox without cntrl.PerformClick?
            }
        }
    }
}

Answer 1

由于您不能使用PerformClick，因此在这种情况下您将无法依赖控件的Click 事件处理程序自动触发。取而代之的是，只需创建一个获取控件的方法并从该控件中找出要执行的操作。示例：

private void pnlButtons_Click(object sender, EventArgs e)
{
    Point ptClick = Control.MousePosition;
    foreach (Control cntrl in pnlButtons.Controls)
    {
        // Make sure the control is visible!
        if (cntrl.Visible)
        {
            // Click close to control?
            if ((ptClick.X > (cntrl.Left - 5)) &&
                (ptClick.X < (cntrl.Right + 5)) &&
                (ptClick.Y > (cntrl.Top - 5)) &&
                (ptClick.Y < (cntrl.Bottom + 5)))
            {
                handleClick (cntrl);
            }
        }
    }
}

private void handleClick(Control c)
{
    if (c == button1)
    {
        // handle button1 click, e.g. by calling its `Click` handler
    }
    else if (c == picureBox1)
    {
        // handle pictureBox1 click
    }
    // et cetera
}

Answer 2

首先，尝试子类化按钮并从您自己的 PerformClick 中调用 click 事件。否则，您可以编写一个获取按钮并执行单击的方法。首先获取控件的句柄，然后 p/调用 Windows API 函数以向其发送 mousedown 然后 mouseup 事件。我相信它是 SendMessage 功能。然后，您所要做的就是编写逻辑以找到最近的按钮并将其传递给函数。或者，将其写为 Button 的扩展方法

https://msdn.microsoft.com/en-us/library/windows/desktop/ms644950%28v=vs.85%29.aspx

编辑： 下面是通过向控件发送 mousedown 和 mouseup 消息来模拟点击的完整代码：

// Windows constants for mouse messages
private const int WM_LBUTTONDOWN        = 0x0201;
private const int WM_LBUTTONUP          = 0x0202;

// P/Invoke for SendMessage
[DllImport("coredll.dll")]
public static extern IntPtr SendMessage(IntPtr hWnd, int nMsg, IntPtr wParam, IntPtr lParam);

// Method to click a control
public void ClickControl(IntPtr hWnd)
{
    // Send a MOUSE_DOWN and MOUSE_UP message to the control to simulate a click
    SendMessage(hWnd, WM_LBUTTONDOWN, IntPtr.Zero, IntPtr.Zero);
    SendMessage(hWnd, WM_LBUTTONUP, IntPtr.Zero, IntPtr.Zero);
}

// Method to handle click event on parent Panel control
private void pnlButtons_Click(object sender, EventArgs e)
{
    // See if the click point is close to a (visible) button and if so, click the button.
    // The user was probably a little imprecise or the screen might need re-calibration.
    Point pt = pnlButtons.PointToClient(Cursor.Position);

    // Now look for any Button / PictureBox controls nearby
    foreach (Control cntrl in pnlButtons.Controls)
    {
        Rectangle inflated = cntrl.Bounds;
        inflated.Inflate(4, 5);
        if (cntrl.Visible && inflated.Contains(pt))
        {
            // Simulate a click on the control
            ClickControl(cntrl.Handle);
            break;
        }
    }
}

Answer 3

将按钮单击处理程序中的所有内容放到一个单独的函数中，并调用该函数而不是触发按钮单击。

private void pnlButtons_Click(object sender, EventArgs e)
{
    Point ptClick = Control.MousePosition;
    foreach (Control cntrl in pnlButtons.Controls)
    {
        // Make sure the control is visible!
        if (cntrl.Visible)
        {
            // Click close to control?
            if ((ptClick.X > (cntrl.Left - 5)) &&
                (ptClick.X < (cntrl.Right + 5)) &&
                (ptClick.Y > (cntrl.Top - 5)) &&
                (ptClick.Y < (cntrl.Bottom + 5)))
            {
                PerformActionsOnClick();
            }
        }
    }
}
private void MyButton_Click(object sender, EventArgs e)
{
    PerformActionsOnClick();
}
void PerformActionsOnClick()
{
    //do your stuff here
}