菜鸟求助，一个关于label移动的问题

Question

代码：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 WindowsFormsApplication19
{
    public partial class Form1 : Form
    {
      
        public Form1()
        {
            InitializeComponent();
        }        private void button1_Click(object sender, EventArgs e)
        {
            if (button1.Top > Form1.ActiveForm.Size.Height || button1.Bottom < 0)
                label1.Top =label1.Top-50;
            else { label1.Top += 50; }
        }        private void button2_Click(object sender, EventArgs e)
        {
            if (button1.Left > Form1.ActiveForm.Size.Width || button1.Right < 0)
                label1.Left -=50;
            else { label1.Left += 50; }
        }

Answer 1

label.Left = label.Left + 10;
if (label.Left > this.Width) label.Left = 0;

Answer 2

 bool moveBottom = true;
        private void button1_Click(object sender, EventArgs e)
        {
            if (moveBottom)
            {
                label1.Top += 50;
                if (label1.Top > this.Height)
                    moveBottom = false;
            }
            else
            {
                label1.Top -= 50;
                if (label1.Top < 0)
                    moveBottom = true;
            }
        }左右移动的仿着写写

Answer 3

你这个移动要和你窗体的大小对的上号，好像你点一下就加10那么你的窗体的大小必须是10的倍数，判断是否等于窗体大小，否则是不会返回的，获取的lable的X,Y的值好像是左上角的，判断完就把lable移回你想要开始的地方

Answer 4

为何不用while去判断  坐标大于或等于了就返回到初始位置!

Answer 5

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;
using System.Collections;namespace cc
{
    public partial class Form1 : Form
    {
        static bool bFlag; //false是向下移，true是向上移        public Form1()
        {
            InitializeComponent();
            bFlag = false;  //初始时向下移
        }        private void btnStart_Click(object sender, EventArgs e)
        {
            int nTop;   //label的x位置
            int nHeith; //lagel的高度
                        nTop = lab1.Top;
            nHeith = lab1.Height;            if ( !bFlag)
            {
                //当前标识是false，向下移
                if (nTop + nHeith + 20 > this.Height)
                {
                    //如果这次移动后将超出窗体的下部，则改为向上移
                    nTop -= 20;
                    lab1.Top = nTop;
                    bFlag = true;
                }
                else
                {
                    nTop += 20;
                    lab1.Top = nTop;
                }
            }
            else
            {
                //当前标识是true,向上移
                if (nTop - 20 < 0)
                {
                    //本次向上移，将会超出窗体的上部，则改为向下移
                    nTop += 20;
                    lab1.Top = nTop;
                    bFlag = false;
                }
                else
                {
                    nTop -= 20;
                    lab1.Top = nTop;
                }            }            this.Text = "Form1" + this.Height.ToString() + " ; lab:" + nTop.ToString() + " ; ";        }        
       
    }
}

Answer 6

    public partial class Form1 : Form
    {
        Button btnStar;
        Button btnStop;
        Label lbl;        int MoveSpeed = 12;
        bool Direction = true;//true is right,false is left
        bool IsRun = true;        public Form1()
        {
            InitializeComponent();
            this.Controls.Add(btnStar = new Button { Text = "Star" });
            this.Controls.Add(btnStop = new Button { Text = "Stop", Top = 25 });
            this.Controls.Add(lbl = new Label
            {
                Width = 20,
                Height = 20,
                Top = this.Height / 2,
                Left = this.Width / 2,
                BackColor = Color.Red
            });                        btnStop.Click += (s, e) => IsRun = false;            btnStar.Click += (s, e) =>
                {
                    IsRun = true;
                    new Thread(() =>
                        {
                            while (IsRun)
                            {
                                Thread.Sleep(60);
                                this.Invoke(new MethodInvoker(() => lbl.Left = Direction ? lbl.Left + MoveSpeed : lbl.Left - MoveSpeed));                                if (lbl.Left < 0)
                                    Direction = true;
                                if (lbl.Left + lbl.Width > this.Width)
                                    Direction = false;
                            }
                        }).Start();
                };
        }
    }

Answer 7

private void button1_Click(object sender, EventArgs e)
        {
            if (button1.Top > Form1.ActiveForm.Size.Height || button1.Bottom < 0)
                label1.Top =label1.Top-50;
            else { label1.Top += 50; }
        }至少标红的地方 应该为label1移动的方向，只根据Label的当前位置是判断不出来的。如果位于窗体中间，可能是向上移动、也可能是向下移动。这个时候只能先约定一个方向。
每次只是在应该转向的时候 调转方向即可。