loadCLodop最好在页面加载完就调用
打印就调用getLodop
LodopFuncs.js 内容

//驱动
//https://scp-tcdn.sf-express.com/scp/soft/SCPPrint_Win32NT_6.570CN.exe
//或

var MainJS = "CLodopfuncs.js",
URL_WS1 = "ws://localhost:8000/" + MainJS,
URL_WS2 = "ws://localhost:18000/" + MainJS,
//+号改为://
URL_HTTP1 = "http+localhost:8000/" + MainJS,
URL_HTTP2 = "http+localhost:18000/" + MainJS,
URL_HTTP3 = "https+localhost.lodop.net:8443/" + MainJS,
LoadJsState;

function getCLodopJsState() {
return LoadJsState
}

function checkOrTryHttp() {
if (window.getCLodop) return LoadJsState = "complete", !0;
if ("loadingB" != LoadJsState && "complete" != LoadJsState) {
    LoadJsState = "loadingB";
    var t = document.head || document.getElementsByTagName("head")[0] || document.documentElement,
        e = document.createElement("script"),
        n = document.createElement("script"),
        r = document.createElement("script");
    e.onload = n.onload = r.onload = n.onerror = r.onerror = function() {
        LoadJsState = "complete"
    }, e.onerror = function(e) {
        n.src = URL_HTTP2, t.insertBefore(n, t.firstChild)
    }, "https:" !== window.location.protocol ? (e.src = URL_HTTP1, t.insertBefore(e, t.firstChild)) : (r.src = URL_HTTP3, t.insertBefore(r, t.firstChild))
}
}

export function getLodop() {
    var t, e = "https://scp-tcdn.sf-express.com/scp/soft/SCPPrint_Win32NT_6.570CN.exe",
        n = "<br><div class='scpprint-tips'>Web打印服务CLodop未安装启动，点击这里<a href=".concat(e, " target='_self'>下载执行安装</a>"),
        r = "<br><div class='scpprint-tips'>Web打印服务CLodop需升级!点击这里<a href=".concat(e, " target='_self'>执行升级</a>"),
        o = "，成功后请刷新本页面或重启浏览器。</div>";
    try {
        t = window.getCLodop()
    } catch (t) {}
    return t || "complete" === LoadJsState ? t ? CLODOP.CVERSION < "4.1.6.0" ? {
        code: 3,
        msg: r + o,
        downloadUrl: e
    } : (t.SET_LICENSES("xxxx", "A8014B09DC3900222D3047E9942A8F3504D", "xxxx", "EA15AFAF29B939797009E405CDEB043768A"), t.SET_LICENSES("THIRD LICENSE", "", "Sf Technology Co., Ltd.", "F5BD5E2D3083D6F7FA2FF6C5DFEB3740F52"), t) : {
        code: 2,
        msg: n + "<br>（若此前已安装过，可<a href='CLodop.protocol:setup' target='_self'>点这里直接再次启动</a>）" + o + "<br>注：xxx</br>",
        downloadUrl: e
    } : {
        code: 4,
        msg: "网页还没下载完毕，请稍等一下再操作。"
    }
}

export function loadCLodop() {
    LoadJsState = "loadingA", !window.WebSocket && window.MozWebSocket && (window.WebSocket = window.MozWebSocket);
    try {
        var WSK1 = new WebSocket(URL_WS1);
        WSK1.onopen = function(t) {
            setTimeout((function() {
                checkOrTryHttp()
            }), 200)
        }, WSK1.onmessage = function(e) {
            window.getCLodop || eval(e.data)
        }, WSK1.onerror = function(e) {
            var WSK2 = new WebSocket(URL_WS2);
            WSK2.onopen = function(t) {
                setTimeout((function() {
                    checkOrTryHttp()
                }), 200)
            }, WSK2.onmessage = function(e) {
                window.getCLodop || eval(e.data)
            }, WSK2.onerror = function(t) {
                checkOrTryHttp()
            }
        }
    } catch (t) {
        checkOrTryHttp()
    }
} 

通过websocket下发打印

import {getLodop} from './LodopFuncs'
import {delExpress} from '@/api/api/order'

export function route(res){

    if(res.type == '1'){
        dy(res.data)
    }
}

async function dy(data){
    console.log(data)
         var LODOP = await getLodop();
         //设置打印机的名称
         console.log(LODOP)
         await LODOP.PRINT_INIT("PDF打印");
        //  await LODOP.SET_PRINTER_INDEX("http://localhost:8080/profile/upload/pdf/fm_76130_standard_YCMFSV33NQE9.pdf");
        console.log(process.env.VUE_APP_BASE_API+data.url)
        // await getFileBase64(process.env.VUE_APP_BASE_API+url).then(res => {
        //     LODOP.SET_PRINT_PAGESIZE(1, 0, 0, 'A7')//1为纵向 2为横向
        //     LODOP.ADD_PRINT_PDF(0, 0, '100%', '100%', res?.split('data:application/pdf;base64,')[1])
        //     // LODOP.ADD_PRINT_PDF(0,0,"100%","100%","Deli GE430-W");//打印机Deli GE430-W
        //     LODOP.PREVIEW();
        // })
        await LODOP.SET_PRINT_PAGESIZE(1, 0, 0, 'A7')//1为纵向 2为横向
        await LODOP.SET_PRINTER_INDEX("Deli GE430-W");
         await LODOP.ADD_PRINT_PDF(10,15,60,130,process.env.VUE_APP_BASE_API+data.url);//打印机Deli GE430-W
        //  await LODOP.ADD_PRINT_PDF(0,0,"100%","100%","Microsoft Print to PDF");
        //打印预览
        // LODOP.PREVIEW();
        //打印
        await LODOP.PRINT(); 
        await delExpress({code:data.code});//删除队列中的第一个

}
/**
 * 加载pdf 并转为base64
 * @param {string} pdfUrl[pdf的链接]
 */
const getFileBase64 = async pdfUrl => {
    let fileData = null
    try {
      fileData = await axios({
        method: 'get',
        url: pdfUrl, // 请求地址
        responseType: 'blob' // 指明服务器返回的数据类型
      })
    } catch {
      fileData = null
    }
    return new Promise((resolve, reject) => {
      if (fileData && fileData.data) {
        const file = new Blob([fileData.data], { type: 'application/pdf' })
        const reader = new FileReader()
        reader.readAsDataURL(file)
        reader.onload = () => resolve(reader.result)
        reader.onerror = error => reject(error)
      } else {
        reject('文件读取错误')
      }
    })
  }