Electron 收据热敏打印机

Receipt thermal printer in Electron(Electron 收据热敏打印机)
本文介绍了Electron 收据热敏打印机的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着小编来一起学习吧!

问题描述

我需要找到一种在 Electron 的 javascript 中打印收据的方法.我已经尝试过 QZ-TRAY,但由于 Electron 无法正常工作.我也尝试过 node-thermal-printer,但它也从未对我有用.这里有人知道如何在不使用 javascript (Electron) 询问用户的情况下打印收据吗?

编辑

Qz-tray 提供了一个非常好的解决方案.

如果您遇到错误 RSVP 未定义,您需要使用此行启用原生 javascript 承诺.

qz.api.setPromiseType(resolver => new Promise(resolver));

解决方案

引用相关评论...

<块引用><块引用>

对于 QZ,我的问题是 RSVP 未定义,而对于 node-thermal-printer,打印机从未打印过."

对于 QZ,它花了 20 秒才找到这个:https://qz.io/wiki/2.0-api-override"

按照评论建议的方式发布解决方案.感谢@gilbert-gabriel 的帮助.

默认情况下启用 RSVP 承诺,但通过以下方式支持原生 JS 承诺:

qz.api.setPromiseType(resolver => new Promise(resolver));

一个更全面的例子:

//安装依赖:/*npm install qz-tray js-sha256*///提供 API 覆盖并开始与 QZ Tray 对话:从'qz-tray'导入*作为qz;从'js-sha256'导入{sha256};qz.api.setSha256Type(data => sha256(data));qz.api.setPromiseType(resolver => new Promise(resolver));qz.websocket.connect().then(qz.printers.getDefault).then(printer => console.log("默认打印机是:" + 打印机)).then(qz.websocket.disconnect).catch(err => console.error(err));

I need to find a way of printing receipts in javascript from Electron. I already tried QZ-TRAY but it doesn't work because of Electron. I also tried node-thermal-printer but it also never worked for me. Does anybody here know how you can print receipts without asking the user in javascript (Electron)?

EDIT

Qz-tray offer a solution that is pretty good and hard to beat.

If you have the error RSVP is not defined you need to enable native javascript promises with this line.

qz.api.setPromiseType(resolver => new Promise(resolver));

解决方案

Quoting the relevant comments...

"Well with QZ my problem was RSVP is not defined and with node-thermal-printer, the printer just never printed."

"for QZ it took all of 20secs to find this: https://qz.io/wiki/2.0-api-override"

Posting as asolution as the comments suggest it worked. Credits to @gilbert-gabriel for the help.

The RSVP promises are enabled by default, but native JS promises are supported via:

qz.api.setPromiseType(resolver => new Promise(resolver));

A more comprehensive example:

// Install dependencies:
/*
   npm install qz-tray js-sha256
*/

// Provide API overrides and start talking to QZ Tray:    
import * as qz from 'qz-tray';
import { sha256 } from 'js-sha256';

qz.api.setSha256Type(data => sha256(data));
qz.api.setPromiseType(resolver => new Promise(resolver));

qz.websocket.connect()
 .then(qz.printers.getDefault)
 .then(printer => console.log("The default printer is: " + printer))
 .then(qz.websocket.disconnect)
 .catch(err => console.error(err));

这篇关于Electron 收据热敏打印机的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持编程学习网!

本站部分内容来源互联网,如果有图片或者内容侵犯您的权益请联系我们删除!

相关文档推荐

Update another component when Formik form changes(当Formik表单更改时更新另一个组件)
Formik validation isSubmitting / isValidating not getting set to true(Formik验证正在提交/isValiating未设置为True)
React Validation Max Range Using Formik(使用Formik的Reaction验证最大范围)
Validation using Yup to check string or number length(使用YUP检查字符串或数字长度的验证)
Updating initialValues prop on Formik Form does not update input value(更新Formik表单上的初始值属性不会更新输入值)
password validation with yup and formik(使用YUP和Formick进行密码验证)