随着移动设备的快速发展，二维码越来越大众普及，今天给大家介绍一下我的总结：
先来两张效果图（左图不带文字说明，右图带文字说明）
1. 从Nuget上找到这一个程序包（这个程序包兼容.net framework 4.7和.net core，之前引用过其他的程序包，发现并不兼容.net framework 4.7）
2.我重载了一个方法GenerateQRCode，用于生成带文字说明和不带文字说明的二维码。不带文字说明的二维码大小尺寸没有加限制，返回的是原始大小，带文字说明的二维码大小限制为了600*600px（包括文字，可以根据需要自行调整），同时，我将二维码的文字说明放在了二维码的下面（当然了，文字位置也是可以自行调整的，后续有时间我会继续补充）
1 using QRCoder;
2 using System;
3 using System.Collections.Generic;
4 using System.Drawing;
5 using System.Drawing.Imaging;
6 using System.IO;
7 using System.Linq;
8 using System.Text;
9 using System.Threading.Tasks;
10
11 namespace App.Common.QRCode
12 {
13 /// <summary>
14 /// 二维码帮助类
15 /// </summary>
16 public class QRCodeHelper
17 {
18 /// <summary>
19 /// 生成二维码图片
20 /// </summary>
21 /// <param name="str"></param>
22 /// <returns></returns>
23 public Bitmap CreateQRimg(string str)
24 {
25 QRCodeGenerator qrGenerator = new QRCodeGenerator();
26 QRCodeData qrCodeData = qrGenerator.CreateQrCode(str, QRCodeGenerator.ECCLevel.Q);
27 QRCoder.QRCode qrCode = new QRCoder.QRCode(qrCodeData);
28 Bitmap bt = qrCode.GetGraphic(20);
29
30 return bt;
31 }
32
33 /// <summary>
34 /// 生成二维码图片流（二维码上含文字）
35 /// </summary>
36 /// <param name="str1">二维码中要传递的数据（地址）</param>
37 /// <param name="str2">二维码上显示的文字说明</param>
38 public byte[] GenerateQRCode(string str1, string str2)
39 {
40 using (Image codeImage = CreateQRimg(str1), strImage = ConvertStringToImage(str2))
41 {
42 Image img = CombineImage(600, 600, codeImage, 60, 50, strImage, 0, 530);
43 using (var stream = new MemoryStream())
44 {
45 img.Save(stream, ImageFormat.Jpeg);
46 //输出图片流
47 return stream.ToArray();
48 }
49 }
50 }
51
52 /// <summary>
53 /// 生成二维码图片流（不含文字）
54 /// </summary>
55 /// <param name="str">二维码中要传递的数据（地址）</param>
56 /// <returns></returns>
57 public byte[] GenerateQRCode(string str)
58 {
59 using (Image codeImage = CreateQRimg(str))
60 {
61 using (var stream = new MemoryStream())
62 {
63 codeImage.Save(stream, ImageFormat.Jpeg);
64
65 return stream.ToArray();
66 }
67 }
68 }
69
70 /// <summary>
71 /// 生成文字图片
72 /// </summary>
73 /// <param name="str"></param>
74 /// <returns></returns>
75 public Image ConvertStringToImage(string str)
76 {
77 Bitmap image = new Bitmap(600, 40, PixelFormat.Format24bppRgb);
78
79 Graphics g = Graphics.FromImage(image);
80
81 try
82 {
83 Font font = new Font("SimHei", 14, FontStyle.Regular);
84
85 g.Clear(Color.White);
86
87 StringFormat format = new StringFormat();
88 format.Alignment = StringAlignment.Center;
89 format.LineAlignment = StringAlignment.Center;
90
91 Rectangle rectangle = new Rectangle(0, 0, 600, 40);
92
93 g.DrawString(str, font, new SolidBrush(Color.Black), rectangle, format);
94
95 return image;
96 }
97 catch (Exception e)
98 {
99 throw e;
100 }
101 finally
102 {
103 GC.Collect();
104 }
105 }
106
107 /// <summary>
108 /// 在画板中合并二维码图片和文字图片
109 /// </summary>
110 /// <param name="width"></param>
111 /// <param name="height"></param>
112 /// <param name="imgLeft"></param>
113 /// <param name="imgLeft_left"></param>
114 /// <param name="imgLeft_top"></param>
115 /// <param name="imgRight"></param>
116 /// <param name="imgRight_left"></param>
117 /// <param name="imgRight_top"></param>
118 /// <returns></returns>
119 public Image CombineImage(int width, int height, Image imgLeft, int imgLeft_left, int imgLeft_top, Image imgRight, int imgRight_left, int imgRight_top)
120 {
121 Bitmap image = new Bitmap(width, height, PixelFormat.Format24bppRgb);
122
123 Graphics g = Graphics.FromImage(image);
124
125 try
126 {
127 g.Clear(Color.White);
128 g.DrawImage(imgLeft, imgLeft_left, imgLeft_top, 500, 500);
129 g.DrawImage(imgRight, imgRight_left, imgRight_top, imgRight.Width, imgRight.Height);
130
131 return image;
132 }
133 catch (Exception e)
134 {
135 throw e;
136 }
137 finally
138 {
139 g.Dispose();
140 }
141 }
142 }
143 }
最后，再补充两个调用方法
1 /// <summary>
2 /// Mvc
3 /// </summary>
4 public class QRCodeController : Controller
5 {
6 /// <summary>
7 /// 显示二维码
8 /// </summary>
9 /// <returns></returns>
10 public ActionResult Index()
11 {
12 var qrCode = new QRCodeHelper();
13 var qrImg = qrCode.GenerateQRCode("https://www.cnblogs.com/wenha");
14
15 var base64 = "data:image/jpeg;base64," + Convert.ToBase64String(qrImg);
16
17 ViewBag.CodeImg = base64;
18 return View();
19 }
20 }
1 /// <summary>
2 /// WebApi
3 /// </summary>
4 public class QRCodeApiController : ApiController
5 {
6 /// <summary>
7 /// 获取二维码图片（base64格式）
8 /// </summary>
9 /// <returns></returns>
10 [HttpGet]
11 public HttpResponseMessage GetQRCode()
12 {
13 var qrCode = new QRCodeHelper();
14
15 var url = "https://www.cnblogs.com/wenha";
16 var image = qrCode.GenerateQRCode(url, "博客园地址");
17
18 var resp = new HttpResponseMessage(HttpStatusCode.OK)
19 {
20 Content = new StringContent("data:image/jpeg;base64," + Convert.ToBase64String(image))
21 };
22
23 return resp;
24 }
25
26 /// <summary>
27 /// 获取二维码图片（图片格式）
28 /// </summary>
29 /// <returns></returns>
30 [HttpGet]
31 public HttpResponseMessage GetQRCodeImg()
32 {
33
34 var qrCode = new QRCodeHelper();
35
36 var url = "https://www.cnblogs.com/wenha";
37 var image = qrCode.GenerateQRCode(url, "博客园地址");
38
39 var resp = new HttpResponseMessage(HttpStatusCode.OK)
40 {
41 Content = new ByteArrayContent(image)
42 };
43 resp.Content.Headers.ContentType = new MediaTypeHeaderValue("image/jpg");
44 return resp;
45 }
46 }