鼠标滚轮事件（C＃） [英] Mouse Wheel Event (C#)

问题描述

我无法在主窗体获得鼠标滚轮事件。

I can't get the Mouse Wheel event in the main form.

作为演示我想出了一个简单的例子：

As a demo I came up with a simple example:

public partial class Form1 : Form
{
    public Form1()
    {
        InitializeComponent();

        this.panel1.MouseWheel += new MouseEventHandler(panel1_MouseWheel);
        this.panel1.MouseMove += new MouseEventHandler(panel1_MouseWheel);

        Form2 f2 = new Form2();
        f2.Show(this);
    }

    private void panel1_MouseWheel(object sender, MouseEventArgs e)
    {
        if(e.Delta != 0)
        Console.Out.WriteLine(e.Delta);
    }
}

public partial class Form2 : Form
{
    public Form2()
    {
        InitializeComponent();

        this.MouseMove += new MouseEventHandler(Form2_MouseMove);
        this.MouseWheel += new MouseEventHandler(Form2_MouseMove);
    }

    private void Form2_MouseMove(object sender, MouseEventArgs e)
    {
        if(e.Delta != 0)
            Console.Out.WriteLine(e.Delta);
    }
}

我得到了窗体2鼠标滚轮事件，但没有Form1的任何想法？

I get the mouse wheel event in Form2 but not Form1 any ideas?

干杯，

詹姆斯

推荐答案

我怀疑OP希望得到滚动事件时，就在鼠标悬停即使专家组没有焦点的面板。

I suspect the OP wants to get scroll events when just the mouse is hovering over the panel even though the panel does not have the focus.

要完成这一行为的方式在此说明：

A way to accomplish this behaviour is explained here:

<一个href=\"http://social.msdn.microsoft.com/forums/en-US/winforms/thread/eb922ed2-1036-41ca-bd15-49daed7b637c/\">http://social.msdn.microsoft.com/forums/en-US/winforms/thread/eb922ed2-1036-41ca-bd15-49daed7b637c/

在这里：

<一个href=\"http://social.msdn.microsoft.com/forums/en-US/winforms/thread/6bfb9287-986d-4c60-bbcc-23486e239384/\">http://social.msdn.microsoft.com/forums/en-US/winforms/thread/6bfb9287-986d-4c60-bbcc-23486e239384/

从一个链接的论坛采取了code段的：

One of the code snippets taken from the linked forum:

using System;
using System.ComponentModel;
using System.Drawing;
using System.Windows.Forms;
using System.Runtime.InteropServices;

namespace WindowsApplication1 {
  public partial class Form1 : Form, IMessageFilter {
    public Form1() {
      InitializeComponent();
      Application.AddMessageFilter(this);
    }

    public bool PreFilterMessage(ref Message m) {
      if (m.Msg == 0x20a) {
        // WM_MOUSEWHEEL, find the control at screen position m.LParam
        Point pos = new Point(m.LParam.ToInt32() & 0xffff, m.LParam.ToInt32() >> 16);
        IntPtr hWnd = WindowFromPoint(pos);
        if (hWnd != IntPtr.Zero && hWnd != m.HWnd && Control.FromHandle(hWnd) != null) {
          SendMessage(hWnd, m.Msg, m.WParam, m.LParam);
          return true;
        }
      }
      return false;
    }

    // P/Invoke declarations
    [DllImport("user32.dll")]
    private static extern IntPtr WindowFromPoint(Point pt);
    [DllImport("user32.dll")]
    private static extern IntPtr SendMessage(IntPtr hWnd, int msg, IntPtr wp, IntPtr lp);
  }
}

这code基本上会拦截所有WM_MOUSEWHEEL事件，并将其重定向到鼠标目前徘徊在控制。该面板不需要具有焦点不再接收轮事件。

This code will basically intercept all wm_mousewheel events and redirect them to the control the mouse is currently hovering over. The panel doesn't need to have the focus anymore to receive the wheel events.

这篇关于鼠标滚轮事件（C＃）的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！