Node.js-如何在视图中显示二维图像结果 [英] Nodejs - How to show qr-image result in view

问题描述

我使用 qr-image 插件为Node.js生成QR码，效果很好。

I use qr-image plugin for Nodejs to generate a QR code and it works pretty good.

问题是在ejs中显示结果图像。

The problem is showing result image in ejs.

var express = require('express');
var router = express.Router();
var qr = require('qr-image');

router.get('/', function(req, res) {
    var code = qr.image("text to show in qr", { type: 'png', ec_level: 'H', size: 10, margin: 0 });
    res.type('png');
    code.pipe(res);
    // res.render('index', { title: 'QR Page', qr: code });
});

当我取消注释最后一行时，nodejs崩溃。
如何发送代码以查看为变量？

When i uncomment last line, nodejs crashs. How to send code to view as a variable?

更新：

此代码在结果页中返回 [object Object] 。

This code returns [object Object] in result page.

var code = qr.image("text to show in qr", { type: 'png', ec_level: 'H', size: 10, margin: 0 });
res.render('index', { title: 'QR Page', qr: code });

也console.log（code）显示如下：

Also console.log(code) shows this:

{ _readableState:
   { highWaterMark: 16384,
     buffer: [],
     length: 0,
     pipes: null,
     pipesCount: 0,
     flowing: false,
     ended: false,
     endEmitted: false,
     reading: false,
     calledRead: false,
     sync: true,
     needReadable: false,
     emittedReadable: false,
     readableListening: false,
     objectMode: false,
     defaultEncoding: 'utf8',
     ranOut: false,
     awaitDrain: 0,
     readingMore: false,
     decoder: null,
     encoding: null },
  readable: true,
  domain: null,
  _events: {},
  _maxListeners: 10,
  _read: [Function] }

推荐答案

您正在尝试将渲染的图像填充到模板引擎中；

You're trying to stuff a rendered image into a template engine; it's not going to work.

您应该在模板中使用图像标签，该图像标签指向响应图像的URL。

You should instead have an image tag in the template that points to a URL that responds with the image.

//基于注释进行编辑

// Edit based on comment

router.get('/qr/:text', function(req,res){
   var code = qr.image(req.params.text, { type: 'png', ec_level: 'H', size: 10, margin: 0 });
   res.setHeader('Content-type', 'image/png');
   code.pipe(res);
}

然后在您的html模板中，将src设置为 / qr /任何文本进行图像标记，您应该形状不错。

Then in your html template, make an image tag with the src set to /qr/whatever text and you should be in good shape.

这篇关于Node.js-如何在视图中显示二维图像结果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IT屋！