给图片添加文字水印

 1         /// <summary>
 2         /// 给图片添加文字水印
 3         /// </summary>
 4         /// <param name="stream">图片流</param>
 5         /// <param name="text">文字水印</param>
 6         /// <param name="watermarkStatus">图片水印位置 0=不使用 1=左上 2=中上 3=右上 4=左中  9=右下</param>
 7         /// <param name="fontsize">字体大小</param>
 8         /// <param name="angle">旋转角度（顺时针）</param>
 9         /// <returns></returns>
10         public static Image AddText2Image(Stream stream, string text, int watermarkStatus,  int fontsize, int angle)
11         {
12             Image img = Image.FromStream(stream);
13             using (var g = Graphics.FromImage(img))
14             using (var brush = new SolidBrush(Color.Red))
15             {
16                 Font font = new Font("宋体", fontsize, FontStyle.Regular, GraphicsUnit.Pixel);
17                g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.High;
18                 g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;
19                 var sizeF = g.MeasureString(text, font);
20 
21                 float xpos = 0;
22                 float ypos = 0;
23                 switch (watermarkStatus)
24                 {
25                     case 1:
26                         xpos = (float)img.Width * (float).01;
27                         ypos = (float)img.Height * (float).01;
28                         break;
29                     case 2:
30                         xpos = ((float)img.Width * (float).50) - (sizeF.Width / 2);
31                         ypos = (float)img.Height * (float).01;
32                         break;
33                     case 3:
34                         xpos = ((float)img.Width * (float).99) - sizeF.Width;
35                         ypos = (float)img.Height * (float).01;
36                         break;
37                     case 4:
38                         xpos = (float)img.Width * (float).01;
39                         ypos = ((float)img.Height * (float).50) - (sizeF.Height / 2);
40                         break;
41                     case 5:
42                         xpos = ((float)img.Width * (float).50) - (sizeF.Width / 2);
43                         ypos = ((float)img.Height * (float).50) - (sizeF.Height / 2);
44                         break;
45                     case 6:
46                         xpos = ((float)img.Width * (float).99) - sizeF.Width;
47                         ypos = ((float)img.Height * (float).50) - (sizeF.Height / 2);
48                         break;
49                     case 7:
50                         xpos = (float)img.Width * (float).01;
51                         ypos = ((float)img.Height * (float).99) - sizeF.Height;
52                         break;
53                     case 8:
54                         xpos = ((float)img.Width * (float).50) - (sizeF.Width / 2);
55                         ypos = ((float)img.Height * (float).99) - sizeF.Height;
56                         break;
57                     case 9:
58                         xpos = ((float)img.Width * (float).99) - sizeF.Width;
59                         ypos = ((float)img.Height * (float).99) - sizeF.Height;
60                         break;
61                 }
62                 g.ResetTransform();
63                 g.TranslateTransform(xpos, ypos);
64                 g.RotateTransform(angle);
65                 g.DrawString(text, font, brush, new PointF(-sizeF.Width / 2, -sizeF.Height / 2));
66             }
67             return img;
68         }