背景

二维码是越来越流行了，很多地方都有可能是使用到。如果是静态的二维码还是比较好处理的，通过在线工具就可以直接生成一张二维码图片，比如：草料二维码。但有的时候是需要动态生成的（根据动态数据生成），这个使用在线就工具就无法实现了。最好是能在代码中直接生成一个二维码图片，这里我就介绍下使用QRCoder类库在代码中生成二维码。

网上生成二维码的组件还是挺多的，但是真正好用且快速的却不多。QRCoder就是我在众多中找到的，它的生成速度快、而且使用也相当方便。

开始编码

1、安装 QRCoder组件。在项目上通过NuGet包管理器来安装，搜索名称：QRCoder

2、在代码中添加引用：using QRCoder;

3、编码生成

  private void RenderQrCode(){string level = comboBoxECC.SelectedItem.ToString();QRCodeGenerator.ECCLevel eccLevel = (QRCodeGenerator.ECCLevel)(level == "L" ? 0 : level == "M" ? 1 : level == "Q" ? 2 : 3);using (QRCodeGenerator qrGenerator = new QRCodeGenerator()){using (QRCodeData qrCodeData = qrGenerator.CreateQrCode(textBoxQRCode.Text, eccLevel)){using (QRCode qrCode = new QRCode(qrCodeData)){pictureBoxQRCode.BackgroundImage = qrCode.GetGraphic(20, Color.Black, Color.White,GetIconBitmap(), (int) iconSize.Value);this.pictureBoxQRCode.Size = new System.Drawing.Size(pictureBoxQRCode.Width, pictureBoxQRCode.Height);//Set the SizeMode to center the image.this.pictureBoxQRCode.SizeMode = PictureBoxSizeMode.CenterImage;pictureBoxQRCode.SizeMode = PictureBoxSizeMode.StretchImage;}}}}

运行效果

上面代码运行的结果

加个Logo吧

还可以加上logo

  private Bitmap GetIconBitmap(){Bitmap img = null;if (iconPath.Text.Length > 0){try{img = new Bitmap(iconPath.Text);}catch (Exception){}}return img;}

完整代码

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using QRCoder;
using System.Drawing.Imaging;
using System.IO;namespace QRCoderDemo
{public partial class Form1 : Form{public Form1(){InitializeComponent();}private void Form1_Load(object sender, EventArgs e){comboBoxECC.SelectedIndex = 0; //Pre-select ECC level "L"RenderQrCode();}private void buttonGenerate_Click(object sender, EventArgs e){RenderQrCode();}private void RenderQrCode(){string level = comboBoxECC.SelectedItem.ToString();QRCodeGenerator.ECCLevel eccLevel = (QRCodeGenerator.ECCLevel)(level == "L" ? 0 : level == "M" ? 1 : level == "Q" ? 2 : 3);using (QRCodeGenerator qrGenerator = new QRCodeGenerator()){using (QRCodeData qrCodeData = qrGenerator.CreateQrCode(textBoxQRCode.Text, eccLevel)){using (QRCode qrCode = new QRCode(qrCodeData)){pictureBoxQRCode.BackgroundImage = qrCode.GetGraphic(20, Color.Black, Color.White,GetIconBitmap(), (int) iconSize.Value);this.pictureBoxQRCode.Size = new System.Drawing.Size(pictureBoxQRCode.Width, pictureBoxQRCode.Height);//Set the SizeMode to center the image.this.pictureBoxQRCode.SizeMode = PictureBoxSizeMode.CenterImage;pictureBoxQRCode.SizeMode = PictureBoxSizeMode.StretchImage;}}}}private Bitmap GetIconBitmap(){Bitmap img = null;if (iconPath.Text.Length > 0){try{img = new Bitmap(iconPath.Text);}catch (Exception){}}return img;}private void selectIconBtn_Click(object sender, EventArgs e){OpenFileDialog openFileDlg = new OpenFileDialog();openFileDlg.Title = "Select icon";openFileDlg.Multiselect = false;openFileDlg.CheckFileExists = true;if (openFileDlg.ShowDialog() == System.Windows.Forms.DialogResult.OK){iconPath.Text = openFileDlg.FileName;if (iconSize.Value == 0){iconSize.Value = 15;}}else{iconPath.Text = "";}}private void btn_save_Click(object sender, EventArgs e){// Displays a SaveFileDialog so the user can save the ImageSaveFileDialog saveFileDialog1 = new SaveFileDialog();saveFileDialog1.Filter = "Bitmap Image|*.bmp|PNG Image|*.png|JPeg Image|*.jpg|Gif Image|*.gif";saveFileDialog1.Title = "Save an Image File";saveFileDialog1.ShowDialog();// If the file name is not an empty string open it for saving.if (saveFileDialog1.FileName != ""){// Saves the Image via a FileStream created by the OpenFile method.using (FileStream fs = (System.IO.FileStream) saveFileDialog1.OpenFile()){// Saves the Image in the appropriate ImageFormat based upon the// File type selected in the dialog box.// NOTE that the FilterIndex property is one-based.ImageFormat imageFormat = null;switch (saveFileDialog1.FilterIndex){case 1:imageFormat = ImageFormat.Bmp;break;case 2:imageFormat = ImageFormat.Png;break;case 3:imageFormat = ImageFormat.Jpeg;break;case 4:imageFormat = ImageFormat.Gif;break;default:throw new NotSupportedException("File extension is not supported");}pictureBoxQRCode.BackgroundImage.Save(fs, imageFormat);fs.Close();}}}public void ExportToBmp(string path){}private void textBoxQRCode_TextChanged(object sender, EventArgs e){RenderQrCode();}private void comboBoxECC_SelectedIndexChanged(object sender, EventArgs e){RenderQrCode();}}
}