微信小程序蓝牙连接打印机打印单据完整Demo【蓝牙小票打印】

文章目录

一、准备工作
- 1. 硬件准备
- 2. 开发环境
二、小程序配置
- 1. 修改app.json
三、完整代码实现
- 1. pages/index/index.wxml
- 2. pages/index/index.wxss
- 3. pages/index/index.js
四、ESC/POS指令说明
五、测试流程
六、常见问题解决
七、进一步优化建议

在这里插入图片描述

下面我将提供一个完整的微信小程序通过蓝牙连接热敏打印机(支持ESC/POS指令)打印订单小票的详细实现方案。本教程假设您使用的是常见的蓝牙热敏打印机(如佳博、芯烨等品牌)。

一、准备工作

1. 硬件准备

蓝牙热敏小票打印机(支持 ESC/POS 指令)
确保打印机已充电/通电
知道打印机的蓝牙名称(如"GBTP-XXXX")

2. 开发环境

微信开发者工具
已注册微信小程序账号
小程序已开通蓝牙权限(在 app.json 中配置)

二、小程序配置

1. 修改app.json

{"pages": ["pages/index/index"],"permission": {"scope.userLocation": {"desc": "你的位置信息将用于蓝牙设备搜索"}},"requiredPrivateInfos": ["getLocation", "chooseAddress", "startBluetoothDevicesDiscovery"]
}

三、完整代码实现

1. pages/index/index.wxml

<view class="container"><button bindtap="searchPrinter">搜索蓝牙打印机</button><view wx:for="{{devices}}" wx:key="deviceId"><view class="device-item" bindtap="connectPrinter" data-device="{{item}}">{{item.name}} ({{item.deviceId}})</view></view><button bindtap="printTest" disabled="{{!connected}}">打印测试小票</button><button bindtap="printOrder" disabled="{{!connected}}">打印订单</button><view class="status">状态: {{status}}</view>
</view>

2. pages/index/index.wxss

.container {padding: 20px;
}.device-item {padding: 15px;border-bottom: 1px solid #eee;
}button {margin-top: 15px;
}.status {margin-top: 20px;color: #666;font-size: 14px;
}

3. pages/index/index.js

Page({data: {devices: [],         // 搜索到的设备列表connected: false,    // 是否已连接deviceId: '',        // 当前连接的设备IDserviceId: '',       // 蓝牙服务UUIDcharacteristicId: '', // 蓝牙特征值UUIDstatus: '未连接',     // 状态提示orderInfo: {         // 示例订单数据orderNo: '20231115001',date: '2023-11-15 14:30',items: [{name: '有机青菜', price: 12.5, quantity: 2},{name: '新鲜番茄', price: 8.0, quantity: 3},{name: '优质土豆', price: 5.5, quantity: 1}],total: 47.5,address: '北京市朝阳区科技园A座1001室',phone: '138****1234'}},// 搜索蓝牙设备searchPrinter() {this.setData({status: '正在搜索蓝牙设备...'});// 初始化蓝牙模块wx.openBluetoothAdapter({success: (res) => {console.log('蓝牙适配器初始化成功', res);this.startDiscovery();},fail: (err) => {console.error('蓝牙适配器初始化失败', err);this.setData({status: '蓝牙初始化失败，请检查手机蓝牙是否开启'});}});},// 开始搜索设备startDiscovery() {wx.startBluetoothDevicesDiscovery({allowDuplicatesKey: false,success: (res) => {console.log('开始搜索设备', res);this.setData({status: '正在搜索设备...'});// 监听找到新设备事件wx.onBluetoothDeviceFound((res) => {const devices = res.devices.filter(device => device.name && device.name.indexOf('GBTP') !== -1);if (devices.length > 0) {this.setData({devices: devices,status: `找到${devices.length}个打印机设备`});wx.stopBluetoothDevicesDiscovery(); // 找到设备后停止搜索}});},fail: (err) => {console.error('搜索设备失败', err);this.setData({status: '搜索设备失败'});}});},// 连接打印机connectPrinter(e) {const device = e.currentTarget.dataset.device;this.setData({status: `正在连接${device.name}...`});// 连接设备wx.createBLEConnection({deviceId: device.deviceId,success: (res) => {console.log('设备连接成功', res);this.setData({deviceId: device.deviceId,status: `已连接${device.name}`});this.getBLEDeviceServices(device.deviceId);},fail: (err) => {console.error('设备连接失败', err);this.setData({status: '连接失败'});}});},// 获取蓝牙服务getBLEDeviceServices(deviceId) {wx.getBLEDeviceServices({deviceId: deviceId,success: (res) => {console.log('获取服务成功', res.services);for (const service of res.services) {// 通常蓝牙打印机的服务UUID是FF00或FFE0if (service.uuid.startsWith('FFE0') || service.uuid.startsWith('FF00')) {this.setData({serviceId: service.uuid});this.getBLEDeviceCharacteristics(deviceId, service.uuid);break;}}},fail: (err) => {console.error('获取服务失败', err);}});},// 获取蓝牙特征值getBLEDeviceCharacteristics(deviceId, serviceId) {wx.getBLEDeviceCharacteristics({deviceId: deviceId,serviceId: serviceId,success: (res) => {console.log('获取特征值成功', res.characteristics);for (const characteristic of res.characteristics) {// 寻找可写的特征值if (characteristic.properties.write) {this.setData({characteristicId: characteristic.uuid,connected: true});console.log('打印机已准备好');break;}}},fail: (err) => {console.error('获取特征值失败', err);}});},// 打印测试小票printTest() {this.setData({status: '正在打印测试小票...'});// ESC/POS指令const buffer = new ArrayBuffer(100);const dataView = new Uint8Array(buffer);// 初始化打印机dataView[0] = 0x1B;dataView[1] = 0x40;// 设置居中dataView[2] = 0x1B;dataView[3] = 0x61;dataView[4] = 0x01;// 设置字体大小dataView[5] = 0x1D;dataView[6] = 0x21;dataView[7] = 0x11;// 打印文本const text = "测试小票\n";for (let i = 0; i < text.length; i++) {dataView[8 + i] = text.charCodeAt(i);}// 换行const lineBreak = "\n\n\n\n";for (let i = 0; i < lineBreak.length; i++) {dataView[8 + text.length + i] = lineBreak.charCodeAt(i);}// 切纸dataView[8 + text.length + lineBreak.length] = 0x1D;dataView[9 + text.length + lineBreak.length] = 0x56;dataView[10 + text.length + lineBreak.length] = 0x42;dataView[11 + text.length + lineBreak.length] = 0x00;// 发送数据this.writeBLECharacteristicValue(buffer);},// 打印订单printOrder() {this.setData({status: '正在打印订单...'});// 创建缓冲区const commands = [];// 初始化打印机commands.push(0x1B, 0x40);// 设置居中commands.push(0x1B, 0x61, 0x01);// 设置大字体commands.push(0x1D, 0x21, 0x11);// 打印标题this.addTextToCommand(commands, "蔬菜配送订单\n");// 恢复默认字体commands.push(0x1D, 0x21, 0x00);// 订单信息this.addTextToCommand(commands, `订单号: ${this.data.orderInfo.orderNo}\n`);this.addTextToCommand(commands, `日期: ${this.data.orderInfo.date}\n\n`);// 商品列表this.addTextToCommand(commands, "----------------------------\n");this.addTextToCommand(commands, "商品名称   单价  数量  小计\n");this.addTextToCommand(commands, "----------------------------\n");this.data.orderInfo.items.forEach(item => {const line = `${item.name}    ${item.price}   ${item.quantity}   ${(item.price * item.quantity).toFixed(2)}\n`;this.addTextToCommand(commands, line);});this.addTextToCommand(commands, "----------------------------\n");this.addTextToCommand(commands, `总计: ¥${this.data.orderInfo.total}\n\n`);// 配送信息this.addTextToCommand(commands, `配送地址: ${this.data.orderInfo.address}\n`);this.addTextToCommand(commands, `联系电话: ${this.data.orderInfo.phone}\n\n`);// 感谢语commands.push(0x1B, 0x61, 0x01); // 居中this.addTextToCommand(commands, "感谢您的惠顾!\n");this.addTextToCommand(commands, "期待再次为您服务\n\n\n");// 切纸commands.push(0x1D, 0x56, 0x42, 0x00);// 转换为ArrayBufferconst buffer = new ArrayBuffer(commands.length);const dataView = new Uint8Array(buffer);commands.forEach((value, index) => {dataView[index] = value;});// 发送数据this.writeBLECharacteristicValue(buffer);},// 辅助方法：添加文本到命令数组addTextToCommand(commands, text) {for (let i = 0; i < text.length; i++) {commands.push(text.charCodeAt(i));}},// 写入蓝牙特征值writeBLECharacteristicValue(buffer) {wx.writeBLECharacteristicValue({deviceId: this.data.deviceId,serviceId: this.data.serviceId,characteristicId: this.data.characteristicId,value: buffer,success: (res) => {console.log('写入成功', res);this.setData({status: '打印指令已发送'});},fail: (err) => {console.error('写入失败', err);this.setData({status: '打印失败'});}});}
});