在C#中拖放面板时移动控件

Question

我想在面板上拖动控件,拖动时我想移动控件并将其位置放到面板上.我已经尝试过mouseUp,mouseDown,MouseMove控件事件.但这不是我要找的东西.我想在面板上触发DragDrop事件并移动控件.我可以这样做吗？如果你能给我一个想法,它会很棒.以下是我的代码的一部分.请指正.非常感谢.

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

namespace DragnDrop
{
    public partial class Form1 : Form
    {

        public Form1()
        {
            InitializeComponent();
        }
        Control mycontrol;
        int x, y;
        //Form1 f = new Form1();
        private void Form1_Load(object sender, EventArgs e)
        {

            foreach (Control c in this.panel1.Controls)
            {
                c.MouseMove += new MouseEventHandler(lblDragger_MouseMove);
                c.MouseUp += new MouseEventHandler(lblDragger_MouseUp);
                c.MouseDown += new MouseEventHandler(pictureBox1_MouseDown);
                c.MouseDoubleClick += new MouseEventHandler(pictureBox1_MouseDown);
            }
            panel2.AllowDrop = true;
            foreach (Control c in this.panel2.Controls)
            {
                c.MouseDown += new MouseEventHandler(pictureBox1_MouseDown);
            }
            panel2.DragOver += new DragEventHandler(panel2_DragOver);
            panel2.DragDrop += new DragEventHandler(panel2_DragDrop);  
        }

        bool isDragging ;
        int  clickOffsetX ;
        int  clickOffsetY ;

        private void pictureBox1_MouseDown(object sender, MouseEventArgs e)
        {
            //  this.Cursor = Cursors.SizeAll;
            //pictureBox1 = (PictureBox)sender;
            Control c = sender as Control;

            //DoDragDrop(pictureBox1.Image, DragDropEffects.Copy);
            // validation = true;
            isDragging = true;
            clickOffsetX = e.X;
            clickOffsetY = e.Y;
            //  c.DoDragDrop(c, DragDropEffects.Move);  
        }

        private void lblDragger_MouseUp(System.Object sender, System.Windows.Forms.MouseEventArgs e)
        {
            isDragging = false;
        }

        private void panel2_DragEnter(object sender, DragEventArgs e)
        {
            if (e.Data.GetDataPresent(typeof(Bitmap)))
            {
                e.Effect = DragDropEffects.Copy;
            }
            else
            {
                e.Effect = DragDropEffects.None;
            }
        }

        private void panel2_DragOver(object sender, DragEventArgs e)
        {
            e.Effect = DragDropEffects.Move;  
        }

        private void panel2_DragDrop(object sender, DragEventArgs e)
        {
            Control c = e.Data.GetData(e.Data.GetFormats()[0]) as Control;
            mycontrol = c;
            if (c != null)
            {
                c.Location = this.panel2.PointToClient(new Point(e.X, e.Y));
                this.panel2.Controls.Add(c);
            }  
        }

        private void lblDragger_MouseMove(System.Object sender,
          System.Windows.Forms.MouseEventArgs e)
        {
            Control c = sender as Control;
            // bool isDragging = true;
            if (isDragging == true)
            {
                c.Left = e.X + c.Left - clickOffsetX;
                c.Top = e.Y + c.Top - clickOffsetY;
            }
        }

        private void panel1_MouseLeave(object sender, EventArgs e)
        {
            Control c = sender as Control;

            c.DoDragDrop(c, DragDropEffects.Move); 
        }
    }
}

Answer 1

如果您的控件已经在面板上并且您只是在同一面板中移动它,那么使用鼠标事件可能是最简单的方法.我的理解是Drag and Drop更多的是在控件甚至应用程序之间传递数据.例如,如果您尝试允许控件在面板之间传输,则拖放将非常适合.

如果你想同时做到这两点,那么这里有一个可能的想法:

1. 使用鼠标事件在同一面板中执行移动拖动.

2. 当您在面板上获得MouseLeave事件时,开始一个DragDrop操作(此处的一些示例)您可以从面板中删除控件或添加某种"灰色"效果以指示控件可能正在离开.

3. 处理目标面板上的DragDrop,并将控件放在拖放的鼠标位置.

这结合了拖动控件的直观感觉,同时还提供了一种将"过去"面板拖到新表面上的方法.