/// <summary>
/// 创造一个验证码图片
/// </summary>
/// <param name="code">图片中的随机字符串</param>
/// <param name="codeLength">生成的验证码所含的字母数量</param>
/// <returns>返回一个随机字符串图片</returns>
public static MemoryStream GenerateImage(out string code, int codeLength = 4)
{
//验证码
code = RandomTool.CreatRandomString(codeLength);
//Bitmap img = null;
//Graphics g = null;
MemoryStream ms;
var random = new Random();
//验证码颜色集合
Color[] c =
{
Color.Black,
Color.Red,
Color.DarkBlue,
Color.Green,
Color.Orange,
Color.Brown,
Color.DarkCyan,
Color.Purple,
Color.Yellow,
Color.Cyan
};
//验证码字体集合
string[] fonts = { "Verdana", "Microsoft Sans Serif", "Comic Sans MS", "Arial", "宋体" };
using (var img = new Bitmap(code.Length * 20, 32))
{
using (var g = Graphics.FromImage(img))
{
g.Clear(Color.White);//背景设为白色
//验证码绘制在g中
for (int i = 0; i < code.Length; i++)
{
var cindex = random.Next(7); //随机颜色索引值
var findex = random.Next(5); //随机字体索引值
Font font = new Font(fonts[findex], 15, FontStyle.Bold); //字体
Brush brush = new SolidBrush(c[cindex]); //颜色
//产生一个轻微的抖动
int shakeX = random.Next(0, 5);
int shakeY = random.Next(0, 10);
float x = 3 + (i * 15) + shakeX; //x坐标
float y = 0 + shakeY; //Y坐标
string character = code.Substring(i, 1); //绘制的字符
g.DrawString(character, font, brush, x, y); //绘制一个验证字符
}
//在随机位置画背景点
for (int i = 0; i < 5; i++)
{
var cindex = random.Next(7);//随机颜色索引值
int x = random.Next(img.Width);
int y = random.Next(img.Height);
using (var pen = new Pen(c[cindex], 2))
{
g.DrawRectangle(pen: pen, x: x, y: y, width: 1, height: 1);
}
}
//随机线条
for (int i = 0; i < 2; i++)
{
var cindex = random.Next(9);//随机颜色索引值
int x1 = random.Next(img.Width);
int y1 = random.Next(img.Height);
int x2 = random.Next(img.Width);
int y2 = random.Next(img.Height);
using (var pen = new Pen(c[cindex], 2))
{
g.DrawLine(pen: pen, x1: x1, y1: y1, x2: x2, y2: y2);
}
}
ms = new MemoryStream(); //生成内存流对象
img.Save(ms, ImageFormat.Jpeg); //将此图像以Png图像文件的格式保存到流中
}
}
return(ms);
}
/// <summary>
/// 创造一个验证码图片
/// </summary>
/// <param name="code">图片中的随机字符串</param>
/// <param name="strLength">字符串长度</param>
/// <returns>返回一个随机字符串图片</returns>
public static MemoryStream Create(out string code, int strLength = 4)
{
code = RandomTool.CreatRandomString(strLength);
//Bitmap img = null;
//Graphics g = null;
MemoryStream ms;
var random = new Random();
//验证码颜色集合
Color[] c =
{
Color.Black,
Color.Red,
Color.DarkBlue,
Color.Green,
Color.Orange,
Color.Brown,
Color.DarkCyan,
Color.Purple,
Color.Yellow,
Color.Cyan
};
//验证码字体集合
string[] fonts = { "Verdana", "Microsoft Sans Serif", "Comic Sans MS", "Arial", "宋体" };
using (var img = new Bitmap(code.Length * 20, 32))
{
using (var g = Graphics.FromImage(img))
{
g.Clear(Color.White);//背景设为白色
//验证码绘制在g中
for (int i = 0; i < code.Length; i++)
{
var cindex = random.Next(7); //随机颜色索引值
var findex = random.Next(5); //随机字体索引值
Font f = new Font(fonts[findex], 15, FontStyle.Bold); //字体
Brush b = new SolidBrush(c[cindex]); //颜色
int ii = 4;
if ((i + 1) % 2 == 0) //控制验证码不在同一高度
{
ii = 2;
}
g.DrawString(code.Substring(i, 1), f, b, 3 + (i * 15), ii);//绘制一个验证字符
}
//在随机位置画背景点
for (int i = 0; i < 5; i++)
{
var cindex = random.Next(7);//随机颜色索引值
int x = random.Next(img.Width);
int y = random.Next(img.Height);
using (var pen = new Pen(c[cindex], 2))
{
g.DrawRectangle(pen: pen, x: x, y: y, width: 1, height: 1);
}
}
//随机线条
for (int i = 0; i < 2; i++)
{
var cindex = random.Next(7);//随机颜色索引值
int x1 = random.Next(img.Width);
int y1 = random.Next(img.Height);
int x2 = random.Next(img.Width);
int y2 = random.Next(img.Height);
using (var pen = new Pen(c[cindex], 2))
{
g.DrawLine(pen: pen, x1: x1, y1: y1, x2: x2, y2: y2);
}
}
ms = new MemoryStream(); //生成内存流对象
img.Save(ms, ImageFormat.Jpeg); //将此图像以Png图像文件的格式保存到流中
}
}
return(ms);
}
