标签：byte image rip oid linear drawrect 最大 异步 length
话不多说，直接上代码
public ValidateCode()
{
}
///
/// 验证码的最大长度
///
public int MaxLength
{
get { return 10; }
}
///
/// 验证码的最小长度
///
public int MinLength
{
get { return 1; }
}
///
/// 生成验证码
///
/// 指定验证码的长度
///
public string CreateValidateCode(int length)
{
int[] randMembers = new int[length];
int[] validateNums = new int[length];
string validateNumberStr = "";
//生成起始序列值
int seekSeek = unchecked((int)DateTime.Now.Ticks);
Random seekRand = new Random(seekSeek);
int beginSeek = (int)seekRand.Next(0, Int32.MaxValue - length * 10000);
int[] seeks = new int[length];
for (int i = 0; i )
{
beginSeek += 10000;
seeks[i] = beginSeek;
}
//生成随机数字
for (int i = 0; i )
{
Random rand = new Random(seeks[i]);
int pownum = 1 * (int)Math.Pow(10, length);
randMembers[i] = rand.Next(pownum, Int32.MaxValue);
}
//抽取随机数字
for (int i = 0; i )
{
string numStr = randMembers[i].ToString();
int numLength = numStr.Length;
Random rand = new Random();
int numPosition = rand.Next(0, numLength - 1);
validateNums[i] = Int32.Parse(numStr.Substring(numPosition, 1));
}
//生成验证码
for (int i = 0; i )
{
validateNumberStr += validateNums[i].ToString();
}
return validateNumberStr;
}
///
/// 创建验证码的图片
///
/// 要输出到的page对象
/// 验证码
public void CreateValidateGraphic(string validateCode, HttpContext context)
{
Bitmap image = new Bitmap((int)Math.Ceiling(validateCode.Length * 12.0), 22);
Graphics g = Graphics.FromImage(image);
try
{
//生成随机生成器
Random random = new Random();
//清空图片背景色
g.Clear(Color.White);
//画图片的干扰线
for (int i = 0; i 25; i++)
{
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.Silver), x1, y1, x2, y2);
}
Font font = new Font("Arial", 12, (FontStyle.Bold | FontStyle.Italic));
LinearGradientBrush brush = new LinearGradientBrush(new Rectangle(0, 0, image.Width, image.Height),
Color.Blue, Color.DarkRed, 1.2f, true);
g.DrawString(validateCode, font, brush, 3, 2);
//画图片的前景干扰点
for (int i = 0; i 100; i++)
{
int x = random.Next(image.Width);
int y = random.Next(image.Height);
image.SetPixel(x, y, Color.FromArgb(random.Next()));
}
//画图片的边框线
g.DrawRectangle(new Pen(Color.Silver), 0, 0, image.Width - 1, image.Height - 1);
//保存图片数据
MemoryStream stream = new MemoryStream();
image.Save(stream, ImageFormat.Jpeg);
//输出图片流
context.Response.Clear();
context.Response.ContentType = "image/jpeg";
context.Response.BinaryWrite(stream.ToArray());
}
finally
{
g.Dispose();
image.Dispose();
}
}
///
/// 得到验证码图片的长度
///
/// 验证码的长度
///
public static int GetImageWidth(int validateNumLength)
{
return (int)(validateNumLength * 12.0);
}
///
/// 得到验证码的高度
///
///
public static double GetImageHeight()
{
return 22.5;
}
//C# MVC 升级版
///
/// 创建验证码的图片
///
/// 要输出到的page对象
/// 验证码
public byte[] CreateValidateGraphic(string validateCode)
{
Bitmap image = new Bitmap((int)Math.Ceiling(validateCode.Length * 12.0), 22);
Graphics g = Graphics.FromImage(image);
try
{
//生成随机生成器
Random random = new Random();
//清空图片背景色
g.Clear(Color.White);
//画图片的干扰线
for (int i = 0; i 25; i++)
{
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.Silver), x1, y1, x2, y2);
}
Font font = new Font("Arial", 12, (FontStyle.Bold | FontStyle.Italic));
LinearGradientBrush brush = new LinearGradientBrush(new Rectangle(0, 0, image.Width, image.Height),
Color.Blue, Color.DarkRed, 1.2f, true);
g.DrawString(validateCode, font, brush, 3, 2);
//画图片的前景干扰点
for (int i = 0; i 100; i++)
{
int x = random.Next(image.Width);
int y = random.Next(image.Height);
image.SetPixel(x, y, Color.FromArgb(random.Next()));
}
//画图片的边框线
g.DrawRectangle(new Pen(Color.Silver), 0, 0, image.Width - 1, image.Height - 1);
//保存图片数据
MemoryStream stream = new MemoryStream();
image.Save(stream, ImageFormat.Jpeg);
//输出图片流
return stream.ToArray();
}
finally
{
g.Dispose();
image.Dispose();
}
}
其中有两个根据数字和字母生成图片验证码的方法，相信大家能够明白，第一种是常规的WebForm后台调用的方法，可以i直接返回相应的验证码图片，第二种则是专门为ASP.NET准备的方法，其实就是筛检了一点东西，然后传入参数也发生了相应的变化，当然，还有点击“看不清，换一张”的时候，会异步获取新的数据，实现方法在文章末尾。
在MVC中的Controller中如下调用：
public ActionResult ShowVCode()
{
ValidateCode vliateCode = new ValidateCode();
string code = vliateCode.CreateValidateCode(4);//产生验证码
Session["validateCode"] = code;
byte[] buffer = vliateCode.CreateValidateGraphic(code);//将验证码画到画布上.
return File(buffer, "image/jpeg");
}
前台页面中如下调用：
实现的效果如下图所示：
点击“看不清换一张”切换验证码代码如下：
如果对大家有帮助，希望点个赞 哈哈
C#系统登录随机验证码生成及其调用方法
标签：byte image rip oid linear drawrect 最大 异步 length
原文地址：https://www.cnblogs.com/wangyinhang/p/9961561.html
