public VerifyImageInfo GenerateImage(string code, int width, int height, Color bgcolor, int textcolor)
{
VerifyImageInfo verifyimage = new VerifyImageInfo();
verifyimage.ImageFormat = ImageFormat.Jpeg;
verifyimage.ContentType = "image/pjpeg";
// 直接指定尺寸, 而不使用外部参数中的建议尺寸
width = 100;
height = 32;
Bitmap bitmap = new Bitmap(width, height, PixelFormat.Format32bppArgb);
Graphics g = Graphics.FromImage(bitmap);
g.SmoothingMode = SmoothingMode.HighSpeed;
g.Clear(bgcolor);
int fixedNumber = textcolor == 2 ? 60 : 0;
Pen linePen = new Pen(Color.FromArgb(Next(50) + fixedNumber, Next(50) + fixedNumber, Next(50) + fixedNumber), 1);
SolidBrush drawBrush = new SolidBrush(Color.FromArgb(Next(100), Next(100), Next(100)));
for (int i = 0; i < 3; i++)
{
g.DrawArc(linePen, Next(20) - 6, Next(20) - 6, Next(width) + 6, Next(height) + 6, Next(-100, 100), Next(-200, 200));
}
Graphics charg = Graphics.FromImage(charbmp);
float charx = -18;
for (int i = 0; i < code.Length; i++)
{
m.Reset();
m.RotateAt(Next(50) - 25, new PointF(Next(3) + 7, Next(3) + 7));
charg.Clear(Color.Transparent);
charg.Transform = m;
//定义前景色为黑色
drawBrush.Color = Color.Black;
charx = charx + 18 + Next(5);
PointF drawPoint = new PointF(charx, 2.0F);
charg.DrawString(code[i].ToString(), fonts[Next(fonts.Length - 1)], drawBrush, new PointF(0, 0));
charg.ResetTransform();
g.DrawImage(charbmp, drawPoint);
}
drawBrush.Dispose();
g.Dispose();
charg.Dispose();
verifyimage.Image = bitmap;
return(verifyimage);
}
protected void Page_Load(object sender, EventArgs e)
{
Context.Response.Cache.SetCacheability(System.Web.HttpCacheability.NoCache);
string vercode = CreateAuthStr(4, false);
Session["vercode"] = vercode;
VerifyImage verifyimg = new VerifyImage();
VerifyImageInfo verifyimginfo = verifyimg.GenerateImage(vercode, 120, 30, System.Drawing.Color.White, 2);
System.Drawing.Bitmap image = verifyimginfo.Image;
System.Web.HttpContext.Current.Response.ContentType = verifyimginfo.ContentType;
image.Save(this.Response.OutputStream, verifyimginfo.ImageFormat);
}