再form中加入这个函数。protected override void OnPaint( System.Windows.Forms.PaintEventArgs e )
{
Point pt1,pt2;
Color color;
color=Color.FromArgb(0,0,0); //配色
Pen pen= new Pen(color,1); //创建画笔
pt1=Point.Empty;
pt2=Point.Empty;
pt1.X=20;
pt2.X=100;
pt1.Y=pt2.Y=60;
e.Graphics.DrawLine(pen, pt1, pt2);
}
{
Point pt1,pt2;
Color color;
color=Color.FromArgb(0,0,0); //配色
Pen pen= new Pen(color,1); //创建画笔
pt1=Point.Empty;
pt2=Point.Empty;
pt1.X=20;
pt2.X=100;
pt1.Y=pt2.Y=60;
e.Graphics.DrawLine(pen, pt1, pt2);
}
http://www.c-sharpcorner.com/Graphics.asp例子一渐变效果：
protected override void OnPaint(PaintEventArgs e) { Graphics g = e.Graphics ; Rectangle rect = new Rectangle(50, 30, 200, 200); LinearGradientBrush lBrush = new LinearGradientBrush(rect, Color.Red, Color.Green,LinearGradientMode.BackwardDiagonal); g.FillRectangle(lBrush, rect); } 例子二弹来弹去的小球：
using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
namespace Animateb2
{
/// <summary>
/// Summary description for Form1.
/// </summary> public class Form1 : System.Windows.Forms.Form
{ public int[,] ballarray = new int[20,20];
public string[] colours = new string[16];
public int g1=1;
public int g2=200;
public Bitmap bmp; private System.Windows.Forms.Timer timer1;
private System.Windows.Forms.MainMenu mainMenu1;
private System.Windows.Forms.MenuItem menuItem1;
private System.Windows.Forms.MenuItem menuItem3;
private System.Windows.Forms.MenuItem AnimateStart;
private System.ComponentModel.IContainer components; public Form1()
{
//
// Required for Windows Form Designer support
//
InitializeComponent();
//colours[0]="Red";
colours[1]="Red";
colours[2]="Blue";
colours[3]="Black";
colours[4]="Yellow";
colours[5]="Crimson";
colours[6]="Gold";
colours[7]="Green";
colours[8]="Magenta";
colours[9]="Aquamarine";
colours[10]="Brown";
colours[11]="Red";
colours[12]="DarkBlue";
colours[13]="Brown";
colours[14]="Red";
colours[15]="DarkBlue";
//
// TODO: Add any constructor code after InitializeComponent call
//
} /// <summary>
/// Clean up any resources being used.
/// </summary> protected override void Dispose( bool disposing )
{
if( disposing )
{
if (components != null)
{
components.Dispose();
}
}
base.Dispose( disposing );
} #region Windows Form Designer generated code /// <summary>
/// Required method for Designer support - do not modify
/// the contents of this method with the code editor.
/// </summary> private void InitializeComponent()
{
this.components = new System.ComponentModel.Container();
this.timer1 = new System.Windows.Forms.Timer(this.components);
this.mainMenu1 = new System.Windows.Forms.MainMenu();
this.menuItem1 = new System.Windows.Forms.MenuItem();
this.AnimateStart = new System.Windows.Forms.MenuItem();
this.menuItem3 = new System.Windows.Forms.MenuItem();
//
// timer1
// this.timer1.Interval = 25;
this.timer1.Tick += new System.EventHandler(this.timer1_Tick);
//
// mainMenu1
//
this.mainMenu1.MenuItems.AddRange(new System.Windows.Forms.MenuItem[] { this.menuItem1}); //
// menuItem1
//
this.menuItem1.Index = 0;
this.menuItem1.MenuItems.AddRange(new System.Windows.Forms.MenuItem[] {
this.AnimateStart,
this.menuItem3}); this.menuItem1.Text = "Animate"; //
// AnimateStart
// this.AnimateStart.Index = 0;
this.AnimateStart.Text = "Start";
this.AnimateStart.Click += new System.EventHandler(this.menuItem2_Click); //
// menuItem3
// this.menuItem3.Index = 1;
this.menuItem3.Text = "Stop";
this.menuItem3.Click += new System.EventHandler(this.menuItem3_Click); //
// Form1
//
this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
this.ClientSize = new System.Drawing.Size(292, 273);
this.Menu = this.mainMenu1;
this.Name = "Form1";
this.Text = "Form1";
}
#endregion /// <summary>
/// The main entry point for the application.
/// </summary> [STAThread]
static void Main()
{
Application.Run(new Form1());
} private void timer1_Tick(object sender, System.EventArgs e)
{
for (int i=1;i<=13;i++)
{
//add direction vectors to coordinates
ballarray[i,1] = ballarray[i,1] + ballarray[i,3];
ballarray[i,2] = ballarray[i,2] + ballarray[i,4];
//if ball goes of to right
if ((ballarray[i,1]+50)>=ClientSize.Width)
{
ballarray[i,1]=ballarray[i,1]-ballarray[i,3];
ballarray[i,3]=-ballarray[i,3];
}
//if ball goes off bottom
else if ((ballarray[i,2]+50)>=ClientSize.Height)
{
ballarray[i,2]=ballarray[i,2]-ballarray[i,4];
ballarray[i,4]=-ballarray[i,4];
}
//if ball goes off to left
else if (ballarray[i,1]<=1)
{
ballarray[i,1]=ballarray[i,1]-ballarray[i,3];
ballarray[i,3]=-ballarray[i,3];
}
//if ball goes over top
else if (ballarray[i,2]<=1)
{
ballarray[i,2]=ballarray[i,2]-ballarray[i,4];
ballarray[i,4]=-ballarray[i,4];
}
}
this.Refresh(); //force repaint of window
}
//Called from timer event when window needs redrawing
protected override void OnPaint(PaintEventArgs e)
{
bmp = new Bitmap(ClientSize.Width,ClientSize.Height, e.Graphics);
Graphics bmpGraphics = Graphics.FromImage(bmp);
// draw here
for (int i=1;i<=13;i++)
{
bmpGraphics.DrawEllipse(new Pen(Color.FromName(colours[i]),2),
ballarray[i,1],ballarray[i,2],50,50);
}
e.Graphics.DrawImageUnscaled(bmp, 0, 0);
//Draw ellipse acording to mouse coords.
e.Graphics.DrawEllipse(new Pen(Color.Red), g1,g2,50,50);
bmpGraphics.Dispose();
bmp.Dispose();
}
private void menuItem2_Click(object sender, System.EventArgs e)
{
Random r = new Random();
//set ball coords and vectors x,y,xv,yv
for (int i=1;i<=13;i++)
{
ballarray[i,1]=+r.Next(10)+1; //+1 means i lose zero values
ballarray[i,2]=+r.Next(10)+1; ballarray[i,3]=+r.Next(10)+1;
ballarray[i,4]=+r.Next(10)+1;
}
timer1.Start();
}
//Called when user moves the mouse
protected override void OnMouseMove(MouseEventArgs m)
{
//Read the mouse x and y coords and use them to draw a circle in OnPaint method
g1=m.X;
g2=m.Y;
}
private void menuItem3_Click(object sender, System.EventArgs e)
{
timer1.Stop();
}
}
}