标签：str ubuntu mat 百度 fonts res oge exif lin
原文:.Net Core 之 图形验证码
通过测试的系统： Windows 8.1 64bit Ubuntu Server 16.04 LTS 64bit Fedora 24 64bit CentOS 7.2 64bit 可以实现以下功能: Open jpg, bmp, ico, png Save jpg, bmp, ico, png Resize image Draw graphics with brush and pen Open font and draw string
以上是官方给的资料。
NuGet引入包，不会的自己百度。
int codeW = 80; int codeH = 30; int fontSize = 16; Random rnd = new Random(); //颜色列表，用于验证码、噪线、噪点 Color[] color = { Color.Black, Color.Red, Color.Blue, Color.Green, Color.Orange, Color.Brown, Color.Brown, Color.DarkBlue }; //字体列表，用于验证码 string[] font = { "Times New Roman" }; //验证码的字符集，去掉了一些容易混淆的字符 //写入Session、验证码加密 //WebHelper.WriteSession("session_verifycode", Md5Helper.MD5(chkCode.ToLower(), 16)); //创建画布 Bitmap bmp = new Bitmap(codeW, codeH); Graphics g = Graphics.FromImage(bmp); g.Clear(Color.White); //画噪线 for (int i = 0; i < 1; i++) { int x1 = rnd.Next(codeW); int y1 = rnd.Next(codeH); int x2 = rnd.Next(codeW); int y2 = rnd.Next(codeH); Color clr = color[rnd.Next(color.Length)]; g.DrawLine(new Pen(clr), x1, y1, x2, y2); } //画验证码字符串 for (int i = 0; i < chkCode.Length; i++) { string fnt = font[rnd.Next(font.Length)]; Font ft = new Font(fnt, fontSize); Color clr = color[rnd.Next(color.Length)]; g.DrawString(chkCode[i].ToString(), ft, new SolidBrush(clr), (float)i * 18, (float)0); } //将验证码图片写入内存流，并将其以 "image/Png" 格式输出 MemoryStream ms = new MemoryStream(); try { bmp.Save(ms, ImageFormat.Png); return ms.ToArray(); } catch (Exception) { return null; } finally { g.Dispose(); bmp.Dispose(); }
直接上图，不会的看这里http://www.cnblogs.com/niao/p/6057860.html
注意：验证码Windows下生成无压力，我用的Ubuntu 14，需要安装gdi包，运行日志中会有提示。
安装方法：
Ubuntu 16.04:
apt-get install libgdiplus cd /usr/lib ln -s libgdiplus.so gdiplus.dll
Fedora 23:
dnf install libgdiplus cd /usr/lib64/ ln -s libgdiplus.so.0 gdiplus.dll
CentOS 7:
yum install autoconf automake libtool yum install freetype-devel fontconfig libXft-devel yum install libjpeg-turbo-devel libpng-devel giflib-devel libtiff-devel libexif-devel yum install glib2-devel cairo-devel git clone https://github.com/mono/libgdiplus cd libgdiplus ./autogen.sh make make install cd /usr/lib64/ ln -s /usr/local/lib/libgdiplus.so gdiplus.dll
88..
标签：str ubuntu mat 百度 fonts res oge exif lin
原文地址：https://www.cnblogs.com/lonelyxmas/p/10306836.html
