joolun微信小程序实现springboot生成二维码，转换为base64保存到数据库中，小程序将base64转换为图片显示在小程序中

程序实现springboot生成二维码，转换为base64保存到数据库中，小程序将base64转换为图片显示在小程序中"/>

joolun微信小程序实现springboot生成二维码，转换为base64保存到数据库中，小程序将base64转换为图片显示在小程序中

先导入Zxing的pom包

 		<dependency><groupId>com.google.zxing</groupId><artifactId>javase</artifactId><version>3.0.0</version></dependency><dependency><groupId>com.google.zxing</groupId><artifactId>core</artifactId><version>3.3.0</version></dependency>

这里是java生成二维码的工具类

package com.joolun.weixin.utils;import java.awt.BasicStroke;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.Shape;
import java.awt.geom.RoundRectangle2D;
import java.awt.image.BufferedImage;
import java.io.*;
import java.util.Hashtable;
import java.util.Random;import javax.imageio.ImageIO;import com.google.zxing.BarcodeFormat;
import com.google.zxing.BinaryBitmap;
import com.google.zxing.DecodeHintType;
import com.google.zxing.EncodeHintType;
import com.google.zxing.MultiFormatReader;
import com.google.zxing.MultiFormatWriter;
import com.google.zxing.Result;
import com.google.zxing.client.j2se.BufferedImageLuminanceSource;
import com.google.zxingmon.BitMatrix;
import com.google.zxingmon.HybridBinarizer;
import com.google.zxing.qrcode.decoder.ErrorCorrectionLevel;
import sun.misc.BASE64Encoder;/*** 二维码工具类**/
public class QrcodeUtils {private static final String CHARSET = "utf-8";private static final String FORMAT = "JPG";// 二维码尺寸private static final int QRCODE_SIZE = 300;// LOGO宽度private static final int LOGO_WIDTH = 60;// LOGO高度private static final int LOGO_HEIGHT = 60;private static BufferedImage createImage(String content, String logoPath, boolean needCompress) throws Exception {Hashtable<EncodeHintType, Object> hints = new Hashtable<EncodeHintType, Object>();hints.put(EncodeHintType.ERROR_CORRECTION, ErrorCorrectionLevel.H);hints.put(EncodeHintType.CHARACTER_SET, CHARSET);hints.put(EncodeHintType.MARGIN, 1);BitMatrix bitMatrix = new MultiFormatWriter().encode(content, BarcodeFormat.QR_CODE, QRCODE_SIZE, QRCODE_SIZE,hints);int width = bitMatrix.getWidth();int height = bitMatrix.getHeight();BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);for (int x = 0; x < width; x++) {for (int y = 0; y < height; y++) {image.setRGB(x, y, bitMatrix.get(x, y) ? 0xFF000000 : 0xFFFFFFFF);}}if (logoPath == null || "".equals(logoPath)) {return image;}// 插入图片QrcodeUtils.insertImage(image, logoPath, needCompress);return image;}/*** 插入LOGO** @param source*            二维码图片* @param logoPath*            LOGO图片地址* @param needCompress*            是否压缩* @throws Exception*/private static void insertImage(BufferedImage source, String logoPath, boolean needCompress) throws Exception {File file = new File(logoPath);if (!file.exists()) {throw new Exception("logo file not found.");}Image src = ImageIO.read(new File(logoPath));int width = src.getWidth(null);int height = src.getHeight(null);if (needCompress) { // 压缩LOGOif (width > LOGO_WIDTH) {width = LOGO_WIDTH;}if (height > LOGO_HEIGHT) {height = LOGO_HEIGHT;}Image image = src.getScaledInstance(width, height, Image.SCALE_SMOOTH);BufferedImage tag = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);Graphics g = tag.getGraphics();g.drawImage(image, 0, 0, null); // 绘制缩小后的图g.dispose();src = image;}// 插入LOGOGraphics2D graph = source.createGraphics();int x = (QRCODE_SIZE - width) / 2;int y = (QRCODE_SIZE - height) / 2;graph.drawImage(src, x, y, width, height, null);Shape shape = new RoundRectangle2D.Float(x, y, width, width, 6, 6);graph.setStroke(new BasicStroke(3f));graph.draw(shape);graph.dispose();}/*** 生成二维码(内嵌LOGO)* 二维码文件名随机，文件名可能会有重复** @param content*            内容* @param logoPath*            LOGO地址* @param destPath*            存放目录* @param needCompress*            是否压缩LOGO* @throws Exception*/public static String encode(String content, String logoPath, String destPath, boolean needCompress) throws Exception {BufferedImage image = QrcodeUtils.createImage(content, logoPath, needCompress);mkdirs(destPath);String fileName = new Random().nextInt(99999999) + "." + FORMAT.toLowerCase();ImageIO.write(image, FORMAT, new File(destPath + "/" + fileName));return fileName;}/*** 生成二维码(内嵌LOGO)* 调用者指定二维码文件名** @param content*            内容* @param logoPath*            LOGO地址* @param destPath*            存放目录* @param fileName*            二维码文件名* @param needCompress*            是否压缩LOGO* @throws Exception*/public static String encode(String content, String logoPath, String destPath, String fileName, boolean needCompress) throws Exception {BufferedImage image = QrcodeUtils.createImage(content, logoPath, needCompress);mkdirs(destPath);fileName = fileName.substring(0, fileName.indexOf(".")>0?fileName.indexOf("."):fileName.length())+ "." + FORMAT.toLowerCase();ImageIO.write(image, FORMAT, new File(destPath + "/" + fileName));return fileName;}/*** 当文件夹不存在时，mkdirs会自动创建多层目录，区别于mkdir．* (mkdir如果父目录不存在则会抛出异常)* @param destPath*            存放目录*/public static void mkdirs(String destPath) {File file = new File(destPath);if (!file.exists() && !file.isDirectory()) {file.mkdirs();}}/*** 生成二维码(内嵌LOGO)** @param content*            内容* @param logoPath*            LOGO地址* @param destPath*            存储地址* @throws Exception*/public static String encode(String content, String logoPath, String destPath) throws Exception {return QrcodeUtils.encode(content, logoPath, destPath, false);}/*** 生成二维码** @param content*            内容* @param destPath*            存储地址* @param needCompress*            是否压缩LOGO* @throws Exception*/public static String encode(String content, String destPath, boolean needCompress) throws Exception {return QrcodeUtils.encode(content, null, destPath, needCompress);}/*** 生成二维码** @param content*            内容* @param destPath*            存储地址* @throws Exception*/public static String encode(String content, String destPath) throws Exception {return QrcodeUtils.encode(content, null, destPath, false);}/*** 生成二维码(内嵌LOGO)** @param content*            内容* @param logoPath*            LOGO地址* @param output*            输出流* @param needCompress*            是否压缩LOGO* @throws Exception*/public static void encode(String content, String logoPath, OutputStream output, boolean needCompress)throws Exception {BufferedImage image = QrcodeUtils.createImage(content, logoPath, needCompress);ImageIO.write(image, FORMAT, output);}/*** 生成二维码** @param content*            内容* @param output*            输出流* @throws Exception*/public static void encode(String content, OutputStream output) throws Exception {QrcodeUtils.encode(content, null, output, false);}/*** 解析二维码** @param file*            二维码图片* @return* @throws Exception*/public static String decode(File file) throws Exception {BufferedImage image;image = ImageIO.read(file);if (image == null) {return null;}BufferedImageLuminanceSource source = new BufferedImageLuminanceSource(image);BinaryBitmap bitmap = new BinaryBitmap(new HybridBinarizer(source));Result result;Hashtable<DecodeHintType, Object> hints = new Hashtable<DecodeHintType, Object>();hints.put(DecodeHintType.CHARACTER_SET, CHARSET);result = new MultiFormatReader().decode(bitmap, hints);String resultStr = result.getText();return resultStr;}/*** 解析二维码** @param path*            二维码图片地址* @return* @throws Exception*/public static String decode(String path) throws Exception {return QrcodeUtils.decode(new File(path));}/*** imgFile 图片本地存储路径*/public static String getImgFileToBase64(String imgFile) {//将图片文件转化为字节数组字符串，并对其进行Base64编码处理InputStream inputStream = null;byte[] buffer = null;//读取图片字节数组try {inputStream = new FileInputStream(imgFile);int count = 0;while (count == 0) {count = inputStream.available();}buffer = new byte[count];inputStream.read(buffer);} catch (IOException e) {e.printStackTrace();} finally {if (inputStream != null) {try {// 关闭inputStream流inputStream.close();} catch (IOException e) {e.printStackTrace();}}}// 对字节数组Base64编码return new BASE64Encoder().encode(buffer);}}

在数据库新增字段，注意这里的数据类型必须是mediumtext

继续在实体类中添加这个字段，在mapper.xml中也加上，方便后续保存

实体类加好以后，我这里是小程序登录时顺便生成二维码，转换为base64，直接set存入数据库中的

		try {//生成二维码String Qrcode = QrcodeUtils.encode("测试sssssssssssssssss", null, "D:\\桌面\\JooLun-wx-master (2)", true);System.out.println("=========================================================="+Qrcode);//转换为base64String imgFileToBase64 = QrcodeUtils.getImgFileToBase64("D:\\桌面\\JooLun-wx-master (2)\\" + Qrcode);System.out.println("aaaaaaaaaa"+imgFileToBase64);//将二维码转换后的数据存入数据库中wxUser.setQrcode(imgFileToBase64);this.updateById(wxUser);} catch (Exception e) {e.printStackTrace();}

这样就可以二维码和base64码了

>小程序端这边就可以接收到一个base64的码

在wxml中添加一个图片

在index.js中转换图片

//将base64码转换为图片var array = wx.base64ToArrayBuffer(wxUser.qrcode)console.log(array)var base64 = wx.arrayBufferToBase64(array)console.log(base64)this.setData({ captchaImage: 'data:image/png;base64,' + base64});

这样就可以了