vue2扫码枪串口模式的使用

1.下载依赖包 serialport　　

1	`npm i serialport`

2.创建文件code-gun.js

var { SerialPort } = require("serialport");
 
// 串口列表
SerialPort.list()
  .then((ports) => {
    ports.forEach((port) => {
      console.log(port);
    });
  })
  .catch((err) => {
    console.error("无法获取串口列表", err);
  });
 
   
const codeGun = {
  entity: null,
  isOpen: false,
  error: null,
  data: null,
};
codeGun.init = function (option, callback) { 
  codeGun.entity &&
    typeof codeGun.entity.close === "function" &&
    codeGun.entity.close();  
  codeGun.entity = new SerialPort(option);
  console.log(codeGun.entity)
  //连接串口后进行写入指令操作
  codeGun.entity.open(function (err) {
    if (!err) {
      console.log("扫码枪连接ok");
      codeGun.isOpen = codeGun.entity.isOpen;
    } else {
      console.log("扫码枪连接失败！");
      console.log(err);
    }
  });
  // close
  codeGun.entity.on("close", function () { 
    codeGun.isOpen = codeGun.entity.isOpen;
  });
  // //指令监听
  codeGun.entity.on("data", function (data) {
    let str = new String(data);
    console.log(str)
    codeGun.data = str.toString();
    typeof callback === "function" && callback();
  });
  // //错误监听
  codeGun.entity.on("error", function (error) {
    console.log("error: " + error);
  });
  return codeGun;
};
codeGun.close = function () { 
  codeGun.isOpen = false;
  codeGun.entity && codeGun.entity.close(); 
};
 
export default codeGun;

3.App.vue 初始化

import codeGun from "@/utils/code-gun"
 
data(){
    return{
      codeScanGun: {
        data: null,
        isOpen: false,
        timer:null,
      }
    }
  },
 
watch: { 
    "codeScanGun.data": {
      handler: function(val) {
        if(val) {
          // 设置当前focus的input元素的值
          let activeElement = document.activeElement;
          if(activeElement.tagName.toUpperCase() === 'INPUT') {
            activeElement.value = val
            // 手动触发input事件，实现数据绑定
            let event = new InputEvent('input', { bubbles: true })
            activeElement.dispatchEvent(event);
          }
          this.$nextTick(() => {
            // 重置扫码枪的值
            this.codeScanGun.data = ""
          })
        }
      }
    },
    "codeScanGun.isOpen": {
      handler: function(val) { 
        if(!val) {
          console.log("扫码枪断开连接！")
          this.timer && clearInterval(this.timer)
          this.timer = setInterval(()=>{
            this.initSMQ()
          },2000)
        }else{ 
          this.timer && clearInterval(this.timer)
        }
      } 
    }
  },    
 
created(){   
    this.codeScanGun = codeGun.init({
         path:"com1",//串口号
         baudRate:9600,//波特率
         autoOpen:false
     });
  },