Jquery与纯javascript相比,为什么我的代码不起作用?
我是Javascript新手,遇到了一个无法解决的问题。 我想用jquery将一个示例重写为纯Javascript 我不明白为什么这样不行。 为什么变量“vorlauf”在函数外为空? 这不是一个全局变量吗? 我附上了控制台输出的图片 未按预期工作(尝试忽略所有杂波…):Jquery与纯javascript相比,为什么我的代码不起作用?,javascript,arrays,scope,Javascript,Arrays,Scope,我是Javascript新手,遇到了一个无法解决的问题。 我想用jquery将一个示例重写为纯Javascript 我不明白为什么这样不行。 为什么变量“vorlauf”在函数外为空? 这不是一个全局变量吗? 我附上了控制台输出的图片 未按预期工作(尝试忽略所有杂波…): 请将所有javascript放在上面 <!DOCTYPE HTML> <html> <head> </head> <body> <div id="char
请将所有javascript放在上面
<!DOCTYPE HTML>
<html>
<head>
</head>
<body>
<div id="chartContainer" style="height: 70%; width: 100%;"></div>
<script src="https://canvasjs.com/assets/script/jquery-1.11.1.min.js"></script>
<script src="https://canvasjs.com/assets/script/canvasjs.min.js"></script>
<script>
window.onload = function() {
let vorlauf = [];
let chart = new CanvasJS.Chart("chartContainer", {
animationEnabled: true,
theme: "light2",
title: {
text: "Vorlauf"
},
axisY: {
title: "Grad",
titleFontSize: 24
},
axisX: {
valueFormatString: "YYYY-MM-DD hh:mm:ss",
labelAngle: -50
},
data: [{
name: "Vorlauf",
showInLegend: true,
type: "spline",
dataPoints: vorlauf
}]
});
$.getJSON("http://localhost/vorlauf.json", function(data) {
for (let i = 0; i < data.length; i++) {
vorlauf.push({
x: new Date(data[i].date + " " + data[i].time),
y: Number(data[i].temp) / 1000
});
}
chart.render();
})
}
</script>
window.onload=函数(){
设vorlauf=[];
让chart=newcanvasjs.chart(“chartContainer”{
animationEnabled:没错,
主题:“light2”,
标题:{
文本:“沃洛夫”
},
axisY:{
标题:“毕业生”,
标题字体:24
},
axisX:{
valueFormatString:“YYYY-MM-DD hh:MM:ss”,
labelAngle:-50
},
数据:[{
姓名:“沃洛夫”,
showInLegend:是的,
类型:“样条曲线”,
数据点:沃洛夫
}]
});
$.getJSON(“http://localhost/vorlauf.json,函数(数据){
for(设i=0;i
fetch
是异步的,因此尽管console.log(“Nach Aufruf getJSON”+vorlauf.length)
发生在程序文本中的fetch之后,但它是在fetch
返回结果之前运行的。感谢您提供的信息。这是为我做的!Thx@Ben&Jonas异步函数getJSON(a){try{var r=await(await fetch(a)).json();for(let i=0;i!DOCTYPE HTML>
<html>
<head>
<script>
window.onload = function() {
let vorlauf = [];
let chart = new CanvasJS.Chart("chartContainer", {
animationEnabled: true,
theme: "light2",
title: {
text: "Vorlauf"
},
axisY: {
title: "Grad",
titleFontSize: 24
},
axisX:{
valueFormatString: "YYYY-MM-DD hh:mm:ss" ,
labelAngle: -50
},
data: [{
name: "Vorlauf",
showInLegend: true,
type: "spline",
dataPoints: vorlauf
}]
});
$.getJSON("http://localhost/vorlauf.json", function(data) {
for(let i = 0; i < data.length; i++) {
vorlauf.push({
x: new Date(data[i].date + " " + data[i].time),
y: Number(data[i].temp) / 1000
});
}
chart.render();
})
}
</script>
</head>
<body>
<div id="chartContainer" style="height: 70%; width: 100%;"></div>
<script src="https://canvasjs.com/assets/script/jquery-1.11.1.min.js"></script>
<script src="https://canvasjs.com/assets/script/canvasjs.min.js"></script>
</body>
</html>
[{"date": "2020-02-22", "temp": "39937", "time": "09:28:59"}, {"date": "2020-02-22", "temp": "39937", "time": "09:29:21"}]
<!DOCTYPE HTML>
<html>
<head>
</head>
<body>
<div id="chartContainer" style="height: 70%; width: 100%;"></div>
<script src="https://canvasjs.com/assets/script/jquery-1.11.1.min.js"></script>
<script src="https://canvasjs.com/assets/script/canvasjs.min.js"></script>
<script>
window.onload = function() {
let vorlauf = [];
let chart = new CanvasJS.Chart("chartContainer", {
animationEnabled: true,
theme: "light2",
title: {
text: "Vorlauf"
},
axisY: {
title: "Grad",
titleFontSize: 24
},
axisX: {
valueFormatString: "YYYY-MM-DD hh:mm:ss",
labelAngle: -50
},
data: [{
name: "Vorlauf",
showInLegend: true,
type: "spline",
dataPoints: vorlauf
}]
});
$.getJSON("http://localhost/vorlauf.json", function(data) {
for (let i = 0; i < data.length; i++) {
vorlauf.push({
x: new Date(data[i].date + " " + data[i].time),
y: Number(data[i].temp) / 1000
});
}
chart.render();
})
}
</script>