1. NetCore ZKweb

在我第一次繪制圖形驗證碼時是采用的ZKweb的繪制庫，奉上代碼參考

 1   public byte[] GetVerifyCode(out string code)
 2         {
 3             code = string.Empty;
 4             int codeW = 80;
 5             int codeH = 30;
 6             int fontSize = 16;
 7             string chkCode = string.Empty;
 
 8             Random rnd = new Random();
 9             //顏色列表，用於驗證碼、噪線、噪點 
10             System.DrawingCore.Color[] color = { Color.Black, Color.Red, Color.Blue, Color.Green, Color.Orange, Color.Brown, Color.Brown, Color.DarkBlue };
11             //字體列表，用於驗證碼 
12             string[] font = { "Times New Roman
 
" };
13             //驗證碼的字符集，去掉了一些容易混淆的字符 
14             char[] character = { ‘2‘, ‘3‘, ‘4‘, ‘5‘, ‘6‘, ‘8‘, ‘9‘, ‘a‘, ‘b‘, ‘d‘, ‘e‘, ‘f‘, ‘h‘, ‘k‘, ‘m‘, ‘n‘, ‘r‘, ‘x‘, ‘y‘, ‘A‘, ‘B‘, ‘C‘, ‘D‘, ‘E‘, ‘F‘, ‘G‘, ‘H‘, ‘J‘, ‘K‘, ‘L‘, ‘M‘, ‘N‘, ‘P‘, ‘R‘, ‘S‘, ‘T‘, ‘W‘, ‘X‘, ‘Y‘ };
15             //生成驗證碼字符串 
16
 
             for (int i = 0; i < 4; i++)
17             {
18                 chkCode += character[rnd.Next(character.Length)];
19             }
20             code = chkCode;
21           
22             //創建畫布
23             Bitmap bmp = new Bitmap(codeW, codeH);
24             Graphics g = Graphics.FromImage(bmp);
25             g.Clear(Color.White);
26             //畫噪線 
27             for (int i = 0; i < 1; i++)
28             {
29                 int x1 = rnd.Next(codeW);
30                 int y1 = rnd.Next(codeH);
31                 int x2 = rnd.Next(codeW);
32                 int y2 = rnd.Next(codeH);
33                 Color clr = color[rnd.Next(color.Length)];
34                 g.DrawLine(new Pen(clr), x1, y1, x2, y2);
35             }
36             //畫驗證碼字符串 
37             for (int i = 0; i < chkCode.Length; i++)
38             {
39                 string fnt = font[rnd.Next(font.Length)];
40                 Font ft = new Font(fnt, fontSize);
41                 Color clr = color[rnd.Next(color.Length)];
42                 g.DrawString(chkCode[i].ToString(), ft, new SolidBrush(clr), (float)i * 18, (float)0);
43             }
44             //將驗證碼圖片寫入內存流，並將其以 "image/Png" 格式輸出 
45             MemoryStream ms = new MemoryStream();
46             try
47             {
48                 bmp.Save(ms, ImageFormat.Png);
49                 return ms.ToArray();
50             }
51             catch (Exception)
52             {
53                 return null;
54             }
55             finally
56             {
57                 g.Dispose();
58                 bmp.Dispose();
59             }
60         }

這個開始用的還不錯，但是今天更新了VS到15.7版這個就產生了一個很惡心的問題，ZKweb的引用庫和項目自帶的Core.All好幾個dll沖突，這兩個一個是ZKweb的依賴庫一個是項目的依賴庫 都沒法重新引用，百度了很久後決定放棄ZKweb.改用SkiaSharp

2. SkiaSharp

這個百度上的搜索結果沒有一個是給了可用代碼的。ε=(′ο｀*)))唉 而且大部分都是一個人放出來的代碼 好吧開始自己整。先上代碼

 1  public IActionResult Code()
 2         {
 3             #region 反射SK支持的全部顏色
 4             //List<SKColor> colors = new List<SKColor>();           
 5             //var skcolors = new SKColors();
 6             //var type = skcolors.GetType();
 7             //foreach (FieldInfo field in type.GetFields())
 8             //{
 9             //    colors.Add( (SKColor)field.GetValue(skcolors));
10             //}
11             #endregion
12 
13             //int maxcolorindex = colors.Count-1;
14             string text = "1A3V";
15             var zu = text.ToList();
16             SKBitmap bmp = new SKBitmap(80, 30);
17             using (SKCanvas canvas = new SKCanvas(bmp))
18             {
19                 //背景色
20                 canvas.DrawColor(SKColors.White);
21                 
22                 using (SKPaint sKPaint = new SKPaint())
23                 {                  
24                     sKPaint.TextSize = 16;//字體大小
25                     sKPaint.IsAntialias = true;//開啟抗鋸齒                   
26                     sKPaint.Typeface = SKTypeface.FromFamilyName("微軟雅黑", SKTypefaceStyle.Bold);//字體
27                     SKRect size = new SKRect();
28                     sKPaint.MeasureText(zu[0].ToString(), ref size);//計算文字寬度以及高度
29                     
30                     float temp = (bmp.Width/4 - size.Size.Width)/2;
31                     float temp1 = bmp.Height - (bmp.Height - size.Size.Height) / 2;                  
32                     Random random = new Random();
33                   
34                     for (int i = 0; i < 4; i++)
35                     {
36                        
37                         sKPaint.Color = new SKColor((byte)random.Next(0,255), (byte)random.Next(0, 255), (byte)random.Next(0, 255));                      
38                         canvas.DrawText(zu[i].ToString(), temp + 20*i, temp1, sKPaint);//畫文字
39                     }     
40                     //幹擾線
41                     for (int i = 0; i < 5; i++)
42                     {
43                         sKPaint.Color = new SKColor((byte)random.Next(0, 255), (byte)random.Next(0, 255), (byte)random.Next(0, 255));                      
44                         canvas.DrawLine(random.Next(0, 40), random.Next(1, 29), random.Next(41, 80), random.Next(1, 29), sKPaint);
45                     }
46                 }              
47                 //頁面展示圖片
48                 using (SKImage img = SKImage.FromBitmap(bmp))
49                 {
50                     using (SKData p = img.Encode())
51                     {
52                         return File(p.ToArray(), "image/Png");
53                     }
54                 }
55             }
56         }

這個最大的好處不依賴任何庫，不用擔心和core自身的dll沖突問題，SkiaSharp的功能還不只這些 英文水平有限好多屬性我沒沒搞明白是什麽，比如如何內容旋轉啥的 呵呵。。 先記錄這些

Net Core 生成圖形驗證碼