窗体界面设计02

 01.渐变色窗体

 Color颜色对象的FromArgb()方法的应用，语法结构：

 public static System.Drawing.Color FromArgb(int red,int green,int blue)

 Pen对象的应用

 Graphics对象的DrawRectangle方法，语法结构：

 public void DrawRectangle(System.Drawing.Pen pen,float x,float y,float width,float height)

        protected override void OnPaintBackground(PaintEventArgs e)
        {
            base.OnPaintBackground(e);
            int y, dy;                              //定义变量
            y = this.ClientRectangle.Location.Y;
            dy = this.ClientRectangle.Height / 256;
            for(int i=255;i>=0;i--)                 //利用For循环语句渐变窗体背景
            {
                Color c=new Color();                //定义颜色对象案例
                //调用Color对象的FromArgb方法
                c=Color.FromArgb(255,i,0);
                SolidBrush sb=new SolidBrush(c);    //定义画笔颜色
                Pen p = new Pen(sb, 1);             //定义画笔
                //绘制矩形
                e.Graphics.DrawRectangle(p, this.ClientRectangle.X, y, this.Width, y + dy);
                y = y + dy;
            }
        }

        private void Form1_DoubleClick(object sender, EventArgs e)
        {
            this.Close();
            Application.Exit();
        }

 02.笑脸窗体

 Panel控件的应用

 GrahpicsPath类的应用

 Point点对象的应用

 AddString方法的应用，语法结构：

public void AddString(
string s,
System.Drawing.FontFamily family,
int style,
float emSize,
System.Drawing.Point origin,
System.Drawing.StringFormat format
)
参数意义：
s:要添加的System.String
family:一个System.Drawing.FontFamily,表示绘制文本所用字体的名称。
style:一个System.Drawing.FontStyle枚举，它表示有关文本的样式信息（粗体、斜体等），并且必须为整数。
emSize:限定字符的Em（字体大小）方框的高度。
origin:一个System.Drawing.Point,它表示文本从其起始的点。
format:指定文本格式设置信息（如行间距和对齐方式）的System.Drawing.StringFormat。

        private void Form2_Load(object sender, EventArgs e)
        {
            this.Left = (SystemInformation.PrimaryMonitorMaximizedWindowSize.Width - this.Width) / 2;
            this.Top = (SystemInformation.PrimaryMonitorMaximizedWindowSize.Height - this.Height) / 2;

            GraphicsPath gp = new GraphicsPath();                               //创建GraphicsPath对象实例
                                                                                //定义矩形区域
            Rectangle rect = new Rectangle(new Point(0, 0), new Size(this.Width , this.Height));
            gp.AddEllipse(rect);                                                //绘制椭圆
            this.Region=new Region(gp);

            GraphicsPath gpl=new GraphicsPath();
            Rectangle rectl=new Rectangle(new Point(0,0),new Size(this.panel1.Width,this.panel1.Height));
            gpl.AddEllipse(rectl);
            this.panel1.Region=new Region(gpl);                                 //绘制左眼

            GraphicsPath gpr = new GraphicsPath();
            Rectangle rectr = new Rectangle(new Point(0, 0), new Size(this.panel2.Width, this.panel2.Height));
            gpr.AddEllipse(rectr);
            this.panel2.Region = new Region(gpr);                               //绘制右眼

            GraphicsPath myPath = new GraphicsPath();
            Rectangle rectm = new Rectangle(0, 0, this.panel3.Width, this.panel3.Height);
            myPath.StartFigure();
            myPath.AddArc(rectm, 0, 180);
            myPath.CloseFigure();
            this.panel3.Region  = new Region(myPath);                           //绘制嘴

            GraphicsPath gpp = new GraphicsPath();
            string stringText = "退出";
            FontFamily family = new FontFamily("宋体");
            int fontStyle = (int)FontStyle.Bold;
            int emSize = 20;
            Point origin = new Point(20, 20);
            StringFormat format = StringFormat.GenericDefault;                   //绘制退出文字
            gpp.AddString(stringText, family, fontStyle, emSize, origin, format);
            this.button1.Region = new Region(gpp);
        }

        private void button1_Click(object sender, EventArgs e)
        {
            if (MessageBox.Show("你确定要退出吗？", "提示信息", MessageBoxButtons.YesNo, MessageBoxIcon.Warning) == DialogResult.Yes)
            {
                Application.Exit();
            }

        }

 03.八边形图形窗体

 利用Graphics对象绘制图案，CreateGraphics方法创建Graphics对象案例

 Pen类的应用

 Brush类的应用:

 SolidBrush:画笔的最简单形式，它用纯色进行绘制

 LinearGradientBrush:使用两种颜色的渐变色进行绘制

 HatchBrush:与SolidBrush相似，但可以从大量预设的图案中选择要使用的图案，而不是纯色。

 TextureBrush:使用纹理进行绘制。

 PathGradientBrush:基于开发人员定义的惟一路径，使用复杂的混合色渐变进行绘制。

 Color类的应用

using System.Drawing.Drawing2D

        private void timer1_Tick(object sender, EventArgs e)
        {
            Graphics g = this.CreateGraphics();                       //定义Graphics对象实例
            Draw2D();                                                 //调用函数Draw2D
        }

        public void Draw2D()
        {
            int i;                                                    //定义整型变量并赋值
            int Sect = 8;
            float r;
            float[] x = new float[31];                                //定义浮点型变量数组
            float[] y = new float[31];
            this.ClientSize = new Size(300, 300);
            r = this.ClientSize.Width / 2;
            Graphics g = this.CreateGraphics();                       //创建Graphics对象案例
            for (i = 0; i < Sect; i++)                                //利用For循环为数组赋值
            {
                x[i] = (float)(r * Math.Cos(i * 2 * Math.PI / Sect) + this.ClientSize.Width / 2);
                y[i] = (float)(r * Math.Sin(i * 2 * Math.PI / Sect) + this.ClientSize.Height / 2);
            }
            for (int m = 0; m < Sect - 1; m++)                        //利用双For循环绘制图案
            {
                for (int n = 0; n < Sect; n++)
                {
                    g.DrawLine(Pens.Red, x[m], y[m], x[n], y[n]);     //绘制红色的直线
                }
            }
        }


        private void Form3_Load(object sender, EventArgs e)
        {
            this.timer1.Enabled = true;                               //计时器可用
            this.TopMost = true;                                      //总在最前
            this.StartPosition = FormStartPosition.CenterScreen;
        }

        private void Form3_DoubleClick(object sender, EventArgs e)
        {
            this.Close();                                             //关闭程序
        }

 04.动态绘制直线和曲线

 MouseUp事件、MouseMove事件和MouseDown事件的应用

 Graphics对象的DrawLine()方法的应用，语法结构：

 public void DrawLine(System.Drawing.Pen pen,float x1,float y1,float x2,float y2)

 Graphics对象的DrawRectangle()方法的应用，语法结构：

 public void DrawRectangle(System.Drawing.Pen pen,float x,float y,float width,float height)

        int startX;         //获取鼠标起始点的X坐标
        int startY;         //获取鼠标起始点的Y坐标
        Graphics g;         //定义Graphics对象实例

        private void Form1_Load(object sender, EventArgs e)
        {
            this.StartPosition = FormStartPosition.CenterScreen;
            this.BackColor = Color.Snow;        //设置窗体背景颜色
        }

        private void Form1_MouseUp(object sender, MouseEventArgs e)
        {
            g = this.CreateGraphics();          //创建Graphics对象实例
            Pen p = new Pen(Color.Red, 4);      //设置画笔颜色和宽度
            if (radioButton1.Checked == true)
            {
                g.DrawLine(p, startX, startY, e.X, e.Y);
            }
        }

        private void Form1_MouseDown(object sender, MouseEventArgs e)
        {
            startX = e.X;                       //为变量赋值
            startY = e.Y;
        }

        private void Form1_MouseMove(object sender, MouseEventArgs e)
        {
            g = this.CreateGraphics();
            Pen p = new Pen(Color.Blue, 2);     //设置画笔颜色和宽度
            if (radioButton2.Checked == true)
            {
                g.DrawRectangle(p, e.X, e.Y, 1, 1); //绘制曲线
            }

        }

        private void button1_Click(object sender, EventArgs e)
        {
            g = this.CreateGraphics();
            g.Clear(Color.Snow);                    //清空窗体背景
        }

        private void button2_Click(object sender, EventArgs e)
        {
            this.Close();
            Application.Exit();
        }

 05.动态绘制验证码

 产生随机数的Random类的应用

 Bitmap对象的SetPixel()方法的应用，语法结构：

 Public void SetPixel(int x,int y,System.Drawing.Color color)

        private string CheckCode()
        {
            int number;                                              //定义变量
            char code;
            string checkCode = String.Empty;
            Random random = new Random();                            //产生非负随机数
            for (int i = 0; i < 4; i++)                              //利用For循环产生4由英文字母或数字组成的字符串
            {
                number = random.Next();
                if (number % 2 == 0)
                    code = (char)('0' + (char)(number % 10));        //随机数字
                else
                    code = (char)('A' + (char)(number % 26));        //随机字母
                checkCode += " " + code.ToString();
            }
            return checkCode;                                        //返回产生的随机数字和字母
        }

        private void CodeImage(string checkCode)
        {
            if(checkCode==null||checkCode.Trim()==String.Empty)
            {
                return;
            }
            System.Drawing.Bitmap image=new System.Drawing.Bitmap((int)Math.Ceiling((checkCode.Length*50.0)),50);
            Graphics g=Graphics.FromImage(image);
            try
            {
                Random random=new Random();                         //产生非负随机数
                g.Clear(Color.White);                               //清空图像背景色
                for (int i = 0; i < 3; i++)                         //绘制图像的背景噪声线
                {
                    int x1 = random.Next(image.Width);
                    int x2 = random.Next(image.Width);
                    int y1 = random.Next(image.Height);
                    int y2 = random.Next(image.Height);
                    g.DrawLine(new Pen(Color.Black), x1, y1, x2, y2);
                }
                Font font=new System.Drawing.Font("Arial",40,(System.Drawing.FontStyle.Bold));
                g.DrawString(checkCode,font,new SolidBrush(Color.Red),2,2);
                                                                   //绘制图像的前景噪声点

                for(int i=0;i<1000;i++)
                {
                    int x=random.Next(image.Width);
                    int y=random.Next(image.Height);
                    image.SetPixel(x,y,Color.FromArgb(random.Next()));
                }
                                                                   //绘制图像的边框线

                //g.DrawRectangle(new Pen(Color.Silver),0,0,image.Width-1,image.Height-1);
                this.pictureBox1.Width=image.Width;
                this.pictureBox1.Height=image.Height;
                this.pictureBox1.BackgroundImage=image;
            }
            catch
            {
            }
        }


        private void Form2_Load(object sender, EventArgs e)
        {
            CodeImage(CheckCode());                               //调用函数CodeImage
        }

        private void button1_Click(object sender, EventArgs e)
        {
            CodeImage(CheckCode());
        }

        private void button2_Click(object sender, EventArgs e)
        {
            Application.Exit();
        }

 06.椭圆及椭圆弧的绘制

 Graphics对象的DrawEllipse()方法的应用，语法结构:

 public void DrawEllipse(System.Drawing.Pen pen,float x,float y,float width,float height)

 Graphics对象的DrawArc()方法的应用，语法结构:

 public void DrawArc(System.Drawing.Pen pen,float x,float y,float widht,float height,float startAngle,float sweepAngle)

 startAngle:从x轴到弧线的点沿顺时针方向度量的角（以度为单位）

 sweepAngle:从startAngle参数到弧线的结束点沿顺时针方向度量的角（以度为单位）

 Graphics对象的FillPie()方法的应用，语法结构:

 public void FillPie(System.Drawing.Brush brush,float x,float y,float width,float height,float startAngle,float sweepAngle)

 

 

        private void button1_Click(object sender, EventArgs e)
        {

            Bitmap bitM = new Bitmap(this.pictureBox1.Width, this.pictureBox1.Height);
            Graphics g = Graphics.FromImage(bitM);
            g.Clear(Color.White);
            g.DrawEllipse(new Pen(Color.Blue), 10, 10, 100, 50);             //绘制椭圆
            this.pictureBox1.BackgroundImage = bitM;
        }

        private void button2_Click(object sender, EventArgs e)
        {
            Bitmap bitM = new Bitmap(this.pictureBox2.Width, this.pictureBox2.Height);
            Graphics g = Graphics.FromImage(bitM);
            g.Clear(Color.White);
            g.DrawEllipse(new Pen(Color.Blue), 30, 10, 70, 50);              //绘制圆
            this.pictureBox2.BackgroundImage = bitM;
        }

        private void button3_Click(object sender, EventArgs e)
        {
            Bitmap bitM = new Bitmap(this.pictureBox3.Width, this.pictureBox3.Height);
            Graphics g = Graphics.FromImage(bitM);
            g.Clear(Color.White);
            g.DrawArc(new Pen(Color.Blue), 10, 10, 90, 50, 30, 180);        //绘制椭圆弧
            this.pictureBox3.BackgroundImage = bitM;
        }

        private void button4_Click(object sender, EventArgs e)
        {
            Bitmap bitM = new Bitmap(this.pictureBox4.Width, this.pictureBox4.Height);
            Graphics g = Graphics.FromImage(bitM);
            g.Clear(Color.White);
            g.FillPie(new SolidBrush(Color.Red), 10, 10, 100, 50, 90, 270); //绘制填充椭圆弧
            g.FillPie(new SolidBrush(Color.Yellow), 10, 10, 100, 50, 90 + 270, 90);
            this.pictureBox4.BackgroundImage = bitM;
        }

        private void button5_Click(object sender, EventArgs e)
        {
            this.Close();
            Application.Exit();
        }

 07.移动鼠标复制坐标区域图像

 PointToScreen()方法的应用，语法结构：

 public System.Drawing.Point PointToScreen(System.Drawing.Point p)

 Size对象的应用

 Graphics对象的CopyFromScreen()方法的应用，语法结构：

 public void CopyFromScreen(int courceX,int sourceY, int destinationX,int destinationY,System.Drawing.Size blockRegionSize)

 参数意义：

 sourceX:位于源矩形左上角的点的x坐标

 sourceY:位于源矩形左上角的点的y坐标

 destinationX:位于目标矩形左上角的点的x坐标

 destinationY:位于目标矩形左上角的点的y坐标

 blockRegionSize:要传输的区域大小

        private void Form4_MouseMove(object sender, MouseEventArgs e)
        {
            Point myp = this.PointToScreen(e.Location);
            Graphics myg = this.CreateGraphics();
            Size mys = new Size(100, 100);
            myg.CopyFromScreen(myp.X - 50, myp.Y - 50, 0, 0, mys);
            myg.Dispose();
        }

 08.动态获取当前程序的图标

 Icon对象的应用

 Graphics对象的DrawImage()方法的应用，语法结构：

 public void DrawImage(System.Drawing.Image image,float x,float y)

 Graphics对象的DrawString()方法的应用，语法结构：

 public void DrawString(string s,System.Drawing.Font font,System.Drawing.Brush brush,float x,float y)

        private void button1_Click(object sender, EventArgs e)
        {
            Icon icon1 = new Icon(this.Icon, 60, 60);                   //定义Icom对象实例
            Graphics myg = this.CreateGraphics();                       //创建Graphics对象实例
            Bitmap bmp = icon1.ToBitmap();                              //创建Bitmap对象实例
            myg.DrawImage(bmp, new Point(100, 20));                     //绘制图标
            myg.DrawString("当前程序的图标高度：" + icon1.Height.ToString(), Font, Brushes.Red, 50, 70);
            myg.DrawString("当前程序的图标宽度:" + icon1.Width.ToString(), Font, Brushes.Red, 50, 90);
        }

        private void button2_Click(object sender, EventArgs e)
        {
            this.Close();
            Application.Exit();
        }

 

 09.动态获取系统图标

 SystemIcons对象的应用

 Graphics对象的DrawIcon()方法的应用，语法结构：

 public void DrawIcon(System.Drawing.Icon icon,int x,int y)

        private void Form6_Paint(object sender, PaintEventArgs e)
        {
            Rectangle[] rects = new Rectangle[9];                     //定义Rectangle数组
            Pen p = new Pen(Color.Red, 2);                            //定义画笔
            int index = 0;
            for (int i = 20; i < 200; i = i + 60)                     //双For循环语句
            {
                for (int j = 20; j < 200; j = j + 60)
                {
                    e.Graphics.DrawRectangle(p, j, i, 60, 60);        //绘制矩形
                    if (index < 3)
                    {
                        rects[index++] = new Rectangle(j, i, 32, 32);
                    }
                    else
                    {
                        rects[index++] = new Rectangle(j, i, 60, 60);
                    }
                }
            }
                                                                     //定义图标数组,并获取系统图标
            Icon[] icons ={
                             SystemIcons.Application,SystemIcons.Asterisk,SystemIcons.Error,
                             SystemIcons.Exclamation,SystemIcons.Hand,SystemIcons.Information,
                             SystemIcons.Shield,SystemIcons.Warning,SystemIcons.WinLogo
                         };
            for (int i = 0; i < icons.Length; i++)                  //利用循环绘制图标
            {
                e.Graphics.DrawIcon(icons[i], rects[i]);
            }

        }

 10.动态打开、显示和缩放图像

 OpenFileDialog控件的使用，属性意义：

 Name:用来设置在程序代码中引用控件时使用的名称。

 FileName:用来设置打开对话框的默认文件名。

 InitialDirectory:用来设置对话框的默认初始目录，如果不指定，则显示为当前目录。

 DefaultExt:用来设置对话框默认的文件扩展名。

 Filter:用来设置对话框的文件类型，注意该属性的写法，如(文本类型*.txt)|*.txt。

 Title:用来设置对话框的标题。

 Multiselect:如果该属性为True,则打开对话框允许同时打开多个文件，如果为False，则一次只能打开一个文件。

        private void button1_Click(object sender, EventArgs e)
        {
            string myname;
            openFileDialog1.Filter = "*.jpg,*.jpeg,*.bmp,*.gif,*.ico,*.png,*.tif,*.wmf|*.jpg;*.jpeg;*.bmp;*.gif;*.ico;*.png;*.tif;*.wmf";
                                                                                 //设置打开图像的类型
            openFileDialog1.ShowDialog();                                        //"打开"对话框
            myname = openFileDialog1.FileName;
            pictureBox1.Image = Image.FromFile(myname);                          //显示打开图像
        }

        private void button2_Click(object sender, EventArgs e)
        {
            if (pictureBox1.Width >= 50)                                        //当图像的宽度值小于50时，就不能再缩小了
            {
                pictureBox1.Width = Convert.ToInt32(pictureBox1.Width * 0.8);
                pictureBox1.Height = Convert.ToInt32(pictureBox1.Height * 0.8);
            }
            else
            {
                MessageBox.Show(this, "图像已是最小，不能再缩小了！",           //提示对话框
                    "提示对话框", MessageBoxButtons.OK, MessageBoxIcon.Warning);
            }

        }

        private void button3_Click(object sender, EventArgs e)
        {
            if (pictureBox1.Width < 310)                                        //当图像的宽度值大于310时，就不能再放大了
            {
                pictureBox1.Width = Convert.ToInt32(pictureBox1.Width * 1.2);
                pictureBox1.Height = Convert.ToInt32(pictureBox1.Height * 1.2);
            }
            else
            {
                MessageBox.Show(this, "图像已是最大，不能再放大了！",           //提示对话框
                    "提示对话框", MessageBoxButtons.OK, MessageBoxIcon.Warning);
            }
        }