using System;using System.Collections.Generic;using System.ComponentModel;using System.Data;using System.Drawing;using System.Linq;using System.Text;using System.Threading.Tasks;using System.Windows.Forms;using System.Threading;namespace 坦克大战0._1{    public partial class Form1 : Form    {        public Form1()        {               InitializeComponent();        }        private void Form1_Load(object sender, EventArgs e)        {          //this.Location = new Point(50, 50);//窗口的位置          //this.DesktopLocation = new Point(50,50);            this.Opacity = 1;//设置透明度            this.Text = "坦克大战0.2";//设置标题            this.SetDesktopLocation(60, 60);//窗口位置            this.StartPosition = FormStartPosition.Manual;            this.Size = new Size(800, 600);            this.AutoSizeMode = AutoSizeMode.GrowAndShrink;//禁止手动调整大小            this.MaximizeBox = false;//使最大化失效            this.BackColor = Color.Orange; //设置背景色        }        static int x = 50, y = 50;        static int vx = x + 15, vy = y - 15;        private void Form1_Paint(object sender, PaintEventArgs e)        {            Color c = this.BackColor;//获取窗口背景色            Pen a = new Pen(Color.Red);//new画笔            a.Width = 5;//设置画笔宽度          //e.Graphics.DrawEllipse(a, 20, 20, 50, 50);            e.Graphics.FillEllipse(a.Brush, x,y,30,30);            e.Graphics.DrawLine(a, x+15, y+15, vx, vy);            this.BackColor = c;                   }        private void Form1_KeyDown(object sender, KeyEventArgs e)        {                        if (e.KeyCode == Keys.W || e.KeyCode == Keys.Up)            {                y -= 5;                vx = x + 15;                vy = y - 15;                this.Refresh();            }            else if (e.KeyCode == Keys.S || e.KeyCode == Keys.Down)            {                            y += 5;                vx = x + 15;                vy = y + 45;                this.Refresh();            }            else if (e.KeyCode == Keys.A || e.KeyCode == Keys.Left)            {                x -= 5;                vx = x - 15;                vy = y + 15;                this.Refresh();            }            else if (e.KeyCode == Keys.D || e.KeyCode == Keys.Right)            {                x += 5;                vx = x + 45;                vy = y + 15;                this.Refresh();            }        }    }}