public static string CreateAuthCodeImg(int width,int height,out string authcode)
{
string db="1,2,3,4,5,6,7,8,9,0,a,b,c,d,e,f,g,h,i,g,k,l,m,n,o,p,q,r,s,t,u,v,w,x,y,z,A,B,C,D,E,F,G,H,I,J,K,L,M,N,O,P,Q,R,S,T,U,V,W,X,Y,Z";
string[] dbStr=db.Split(',');
string codeStr=string.Empty;
Random rand=new Random();
for(int i=0;i<4;i++)
{
codeStr+=dbStr[rand.Next(dbStr.Length)];
}
Bitmap map=new Bitmap(width,height);
Graphics g=Graphics.FromImage(map);
WebColorConverter color=new WebColorConverter();
g.Clear((Color)color.ConvertFromString("#FAE264"));
//图片背景噪音线
for(int i=0;i<12;i++)
{
int x1=rand.Next(map.Width);
int x2=rand.Next(map.Width);
int y1=rand.Next(map.Height);
int y2=rand.Next(map.Height);
g.DrawLine(new Pen(Color.LightGray),x1,y1,x2,y2);
}
Font font=new Font("Arial",15,FontStyle.Regular|FontStyle.Italic);
System.Drawing.Drawing2D.LinearGradientBrush brush = new System.Drawing.Drawing2D.LinearGradientBrush(
new Rectangle(0,0,map.Width,map.Height),Color.Blue,Color.Gray,1.2f,true);
g.DrawString(codeStr,font,brush,0,0);
authcode = codeStr;
//图片前景噪音点
//for(int i=0;i<10;i++)
//{
// int x=rand.Next(map.Width);
// int y=rand.Next(map.Height);
// map.SetPixel(x,y,Color.White);
//}
//画图片边框
//g.DrawRectangle(new Pen(Color.Black),0,0,map.Width-1,map.Height-1);
//MemoryStream stream=new MemoryStream();
//map.Save(stream,System.Drawing.Imaging.ImageFormat.Gif);
//HttpContext.Current.Response.ClearContent();
//HttpContext.Current.Response.ContentType = "image/gif";
//HttpContext.Current.Response.BinaryWrite(stream.ToArray());
string fileName="ViewPage\\Images\\AuthCodeImg\\"+DateTime.Now.ToFileTime()+".gif";
string path = HttpContext.Current.Server.MapPath("~");
map.Save(path+fileName);
g.Dispose();
map.Dispose();
return "~//"+fileName.Replace("\\","/");
}
/*产生验证图片*/
public void CreateImages(string code)
{
Bitmap image = new Bitmap(60, 20);
Graphics g = Graphics.FromImage(image);
WebColorConverter ww = new WebColorConverter();
g.Clear((Color)ww.ConvertFromString("#ffffff"));
Random random = new Random();
//画图片的背景噪音线
for (int i = 0; i < 10; i++)
{
int x1 = random.Next(100);
int x2 = random.Next(100);
int y1 = random.Next(40);
int y2 = random.Next(40);
g.DrawLine(new Pen(Color.LightGray), x1, y1, x2, y2);
}
Font font = new Font("Arial", 12, FontStyle.Bold | FontStyle.Italic);
System.Drawing.Drawing2D.LinearGradientBrush brush = new System.Drawing.Drawing2D.LinearGradientBrush(
new Rectangle(0, 0, image.Width, image.Height), Color.Black, Color.Gray, 1.2f, true);
//画验证码字符串
for (int i = 0; i < code.Length; i++)
{
g.DrawString(code[i].ToString(), font, brush, i * 14 + 2, 2);
}
//画图片的前景噪音点
//for (int i = 0; i < 300; i++)
//{
// int x = random.Next(image.Width);
// int y = random.Next(image.Height);
// image.SetPixel(x, y, Color.LightGray);
//}
//画图片的边框线
g.DrawRectangle(new Pen(Color.Silver), 0, 0, image.Width - 1, image.Height - 1);
Response.Buffer = true;
Response.ExpiresAbsolute = System.DateTime.Now.AddMilliseconds(0);
Response.Expires = 0;
Response.CacheControl = "no-cache";
Response.AppendHeader("Pragma", "No-Cache");
//将验证码图片写入内存流，并将其以 "image/Png" 格式输出
System.IO.MemoryStream ms = new System.IO.MemoryStream();
try
{
image.Save(ms, System.Drawing.Imaging.ImageFormat.Png);
Response.ClearContent();
Response.ContentType = "image/Png";
Response.BinaryWrite(ms.ToArray());
}
finally
{
//显式释放资源
g.Dispose();
image.Dispose();
}
}
/// <summary>
/// #ff00ff, #f0f => color
/// </summary>
/// <param name="text"></param>
/// <returns></returns>
private Color ConvertStringToColor(string text)
{
if (!string.IsNullOrEmpty(text))
{
Color r = Color.White;
WebColorConverter wcc = new WebColorConverter();
text.Trim();
text = text.Replace("#", "");
if (text.Length == 6)
{
r = (Color)wcc.ConvertFromString("#" + text);
}
if (text.Length == 3)
{
text = string.Format("{0}{0}{1}{1}{2}{2}",
text[0], text[1], text[2]);
r = (Color)wcc.ConvertFromString("#" + text);
}
return r;
}
return Color.White;
}