c＃在任何地方检测鼠标点击（表格内外）

Question

是否可以在if语句中的任何位置（表单内部和外部）检测鼠标单击（左/右）？如果有可能，怎么样？

if(MouseButtons.LeftButton == MouseButtonState.Pressed){

...

}

Answer 1

如果我理解你需要“从窗外点击”并且Hans Passant的建议不符合您的需求，那么这是一个入门者。您可能需要为Form1_Click添加事件处理程序。

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace WindowsFormsApp1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {

        }

        Mutex checking = new Mutex(false);
        AutoResetEvent are = new AutoResetEvent(false);
        //You could create just one handler, but this is to show what you need to link to
        private void Form1_MouseLeave(object sender, EventArgs e)
        {
            StartWaitingForClickFromOutside();
        }

        private void Form1_Leave(object sender, EventArgs e)
        {
            StartWaitingForClickFromOutside();
        }

        private void Form1_Deactivate(object sender, EventArgs e)
        {
            StartWaitingForClickFromOutside();
        }

        private void StartWaitingForClickFromOutside()
        {
            if (checking.WaitOne(10))
            {
                var ctx = new SynchronizationContext();
                are.Reset();

                Task.Factory.StartNew(() =>
                {
                    while (true)
                    {
                        if (are.WaitOne(1))
                        {
                            break;
                        }
                        if (MouseButtons == MouseButtons.Left)
                        {
                            ctx.Send(CLickFromOutside, null);
                            //you might need to put in a delay here and not break depending on what you want to accomplish
                            break;
                        }
                    }

                    checking.ReleaseMutex();
                });
            }
        }

        private void CLickFromOutside(object state)
        {
            MessageBox.Show("Clicked from outside of the window");
        }


        private void Form1_MouseEnter(object sender, EventArgs e)
        {
            are.Set();
        }

        private void Form1_Activated(object sender, EventArgs e)
        {
            are.Set();
        }

        private void Form1_Enter(object sender, EventArgs e)
        {
            are.Set();
        }

        private void Form1_VisibleChanged(object sender, EventArgs e)
        {
            if (this.Visible == true)
            {
                are.Set();
            }
            else
            {
                StartWaitingForClickFromOutside();
            }
        }
    }
}

如果我不正确地理解你，你可能会觉得这很有用：Pass click event of child control to the parent control

Answer 2

当用户在窗体控件外部单击时，它会失去焦点，您可以使用它。这意味着您必须使用窗体控件的_Deactivate(object sender, EventArgs e)事件才能使其工作。因为当表单失去焦点并且不再是活动表单时将触发。让Form1成为形式，然后事件将如下：

private void Form1_Deactivate(object sender, EventArgs e)
{
    // Your code here to handle this event
}