使用的 C# winform
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; namespace GDI_ { public partial class Form1 : Form { public Form1() { InitializeComponent(); } private void Form1_Load(object sender, EventArgs e) { // 一根笔 绘制直线的对象 pen 颜色 Brush Brushes SolidBrush color 一张纸(图面) Graphics 两点 Point } private void button1_Click(object sender, EventArgs e) { //创建GDI图面对象 //Graphics g = new Graphics(); 没有定义构造函数 //创对象 // 1 在堆中开空间 2 在开辟的空间创对象 3 调用构造函数 Graphics g = this.CreateGraphics(); //创建画笔对象 画笔 //1 //Pen pen = new Pen(Brushes.Yellow);//Brush 点不出来 看复数 //2 直接给笔上色 Pen pen = new Pen(Color.Yellow);// //Pen pen = new Pen(new Brush(Color.Yellow));Brush 抽象类报错 //创建两个点 Point p1 = new Point(30, 50); Point p2 = new Point(250, 250); g.DrawLine(pen, p1, p2); } int i = 0; private void Form1_Paint(object sender, PaintEventArgs e) { i++; label1.Text = i.ToString(); //创建GDI对象 //Graphics g = new Graphics(); //创对象 // 1 在堆中开空间 2 在开辟的空间创对象 3 调用构造函数 Graphics g = this.CreateGraphics(); //创建画笔对象 画笔 Pen pen = new Pen(Brushes.Yellow);// 复数形式 返回对象 //创建两个点 Point p1 = new Point(30, 50); Point p2 = new Point(250, 250); g.DrawLine(pen, p1, p2); } private void button2_Click(object sender, EventArgs e) { Graphics g = this.CreateGraphics(); Pen pen = new Pen(Brushes.Yellow); Size si = new System.Drawing.Size(80, 80); Rectangle rec = new Rectangle(new Point(50, 50), si); // 矩形对象 g.DrawRectangle(pen, rec); } private void button3_Click(object sender, EventArgs e) { Graphics g = this.CreateGraphics(); Pen pen = new Pen(Brushes.Blue); Size si = new System.Drawing.Size(80, 80); Rectangle rec = new Rectangle(new Point(100, 100), si); g.DrawPie(pen, rec, 60, 60);//他要什么 我们就给什么 //Draw 画 在图上绘制 Graphics } private void button4_Click(object sender, EventArgs e) { Graphics g = this.CreateGraphics(); Font f = new System.Drawing.Font("宋体", 20, FontStyle.Underline); g.DrawString("asd520", f, Brushes.Red, new Point(100, 200)); } } }
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; namespace GDI_验证码 { public partial class Form1 : Form { public Form1() { InitializeComponent(); } //点击更换验证码 private void pictureBox1_Click(object sender, EventArgs e) { //1 产生随机数 Random r = new Random(); string str = null; for (int i = 0; i < 5; i++) { int rNumber = r.Next(0, 10); str += rNumber; } //MessageBox.Show(str); // 画一个图片 把文本放到图片里面去 //创建GDI对象 Bitmap bmp = new Bitmap(150, 40);//创建位图 //位图 操作系统中 默认的图片类型 其实就是位图(.bmp) Graphics g = Graphics.FromImage(bmp); //对象从图片来 就是在图片上绘制 // 画数字 for (int i = 0; i < 5; i++) { Point p = new Point(i * 20, 0); string[] fonts = { "宋体", "微软雅黑", "黑体", "隶书", "仿宋" }; Color[] colors = { Color.Yellow, Color.Blue, Color.Red, Color.Black, Color.Green }; g.DrawString(str[i].ToString(), new Font(fonts[r.Next(0, 5)], 20, FontStyle.Bold), new SolidBrush(colors[r.Next(0, 5)]), p); } //画线 for (int i = 0; i < 20; i++) {//线必须在验证码图片里面 Point p1 = new Point(r.Next(0, bmp.Width), r.Next(0, bmp.Height)); Point p2 = new Point(r.Next(0, bmp.Width), r.Next(0, bmp.Height)); g.DrawLine(new Pen(Brushes.Green), p1, p2); } //画点 for (int i = 0; i < 500; i++) { //创建点 Point p = new Point(r.Next(0, bmp.Width), r.Next(0, bmp.Height)); bmp.SetPixel(p.X, p.Y, Color.Black);//再在图上画点 } //将图片镶嵌到picturebox中 pictureBox1.Image = bmp; } } }