我正在创建一个 Web 应用程序来实时可视化我房间的温度。目前我用Raspberry读取该值，然后加载数据库Mongodb。现在要在浏览器上实时显示它，我该怎么做？我将 Node.js 和 vue.js 与 Express 一起使用。如何实时将值传递给Vue.js？
var App = Vue.component('App',{
template: "<h1> {{title}} </h1>",
data() {
let test= "hello";
return {title: test};
}
});
new Vue({
el:"#app"
});<div id="app">
<App></App>
</div>最佳答案
你的后端代码应该是这样的:
//get the value from db
//create a variable tmp that will receives temperature from db
let tmp;
var router = express.Router();
router.get('/temperature', function(req, res) {
res.json({
temperature: tmp
});
});
app.use('/api', router);
在前面您可以访问该 api :
localhost:8080/api/temperature
并使用 axios您可以调用您的后端并实时返回温度
var App = Vue.component('App', {
template: "<h1> {{temperature}} </h1>",
data() {
return {
temperature: 0
};
},
created: function() {
this.fetchTemp('api/temperature');
setInterval(()=> {
this.fetchItems('api/temperature');
}, 500);
},
methods: {
fetchTemp(uri) {
axios.get(uri).then((res) => {
this.temperature = res.data.temperature;
});
},
}
});
I tried to simulate your use case by getting the current time from REST API and show it every second new Vue({
el: '#app',
data() {
return {
now: 0
};
},
created: function() {
this.fetchTemp('https://script.googleusercontent.com/a/macros/esi.dz/echo?user_content_key=ypoXRw1nVHj-h1VRDmh6TXSI1VpIPWW7Qo2n9El6RqoxAJ3v28nBI9bDY_4UAE0TQJ3pSozxpbTiRvFpmD8pvcTkGSnPAtgRm5_BxDlH2jW0nuo2oDemN9CCS2h10ox_nRPgeZU6HP_B2BW4qWwVPUuHIcJ3mEdrfLIfNZsYUQi0c--vxV_3BX606CngcowlqSfFH8SSiqMPrUuXDMsd72r-P39_jlVDMh0BMLnMwXU02UuEHWiuob4ULL2SJgrtyBAf43AAwP8&lib=MwxUjRcLr2qLlnVOLh12wSNkqcO1Ikdrk');
setInterval(() => {
this.fetchTemp('https://script.googleusercontent.com/a/macros/esi.dz/echo?user_content_key=ypoXRw1nVHj-h1VRDmh6TXSI1VpIPWW7Qo2n9El6RqoxAJ3v28nBI9bDY_4UAE0TQJ3pSozxpbTiRvFpmD8pvcTkGSnPAtgRm5_BxDlH2jW0nuo2oDemN9CCS2h10ox_nRPgeZU6HP_B2BW4qWwVPUuHIcJ3mEdrfLIfNZsYUQi0c--vxV_3BX606CngcowlqSfFH8SSiqMPrUuXDMsd72r-P39_jlVDMh0BMLnMwXU02UuEHWiuob4ULL2SJgrtyBAf43AAwP8&lib=MwxUjRcLr2qLlnVOLh12wSNkqcO1Ikdrk');
}, 1000);
},
methods: {
fetchTemp(uri) {
axios.get(uri).then((res) => {
this.now = new Date(res.data.fulldate).toLocaleString();
}).catch(err => {});
}
}
})<!DOCTYPE html>
<html lang="en" dir="ltr">
<head>
<meta charset="utf-8">
<title></title>
<script src="https://unpkg.com/vue@2.5.17/dist/vue.js"></script>
<script src="https://unpkg.com/axios/dist/axios.min.js"></script>
<script src="https://unpkg.com/vue-axios@2.1.4/dist/vue-axios.min.js"></script>
</head>
<body>
<div id="app">
<h1> Now : {{now}} </h1>
</div>
</body>
</html>关于node.js - 使用vuejs和nodejs从mongodb数据库读取数据，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/53249384/