Django结合ECharts实现数据动态实时曲线展示

<!DOCTYPE html>
<html>
 
<head>
 
	{% load static %}
	<script src="{% static 'myapp/json2.js'%}"></script>
	<script src="{% static 'myapp/echarts.js'%}"></script>
	<script src="{% static 'myapp/matplotlib.js'%}"></script>
 
	<meta charset="utf-8">
 
</head>
 
<body>
 
	<div id="main" style="background-color:#eceaea; width: 800px; height:600px;"></div>
 
	<div id="myDiv">
		<h2>使用 AJAX 修改该文本内容</h2></div>
	<button type="button" οnclick="loadXMLDoc()">修改内容</button>
 
 
 
	<script>
		var json = {{myContext | safe}}
		var jstr = JSON.stringify(json)
		var option = JSON.parse(jstr)
		// console.log(option)
 
		<!-- 为ECharts准备一个具备大小（宽高）的Dom -->
		// 基于准备好的dom，初始化echarts实例
		var myChart = echarts.init(document.getElementById('main'), 'matplotlib');
 
		// 使用刚指定的配置项和数据显示图表。
		myChart.setOption(option);
 
 
		function loadXMLDoc() {
			var xmlhttp;
			if (window.XMLHttpRequest) {
				// IE7+, Firefox, Chrome, Opera, Safari 浏览器执行代码
				xmlhttp = new XMLHttpRequest();
			} else {
				// IE6, IE5 浏览器执行代码
				xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
			}
			xmlhttp.onreadystatechange = function() {
				if (xmlhttp.readyState == 4 && xmlhttp.status == 200) {
					//document.getElementById("myDiv").innerHTML=xmlhttp.responseText;
					//content = "{{ myContext }}";
					//console.log(content)
 
					//var json = xmlhttp.responseText;
					//var jstr = JSON.stringify(json)
					option = JSON.parse(xmlhttp.responseText)
 
					// 使用刚指定的配置项和数据显示图表。
					myChart.setOption(option);
					//console.log(option);
 
				}
			}
			xmlhttp.open("GET", "/myapp/mytext", true);
			xmlhttp.send();
		}
 
 
		setInterval(loadXMLDoc, 500);
	</script>
 
</body>
 
</html>

def mytext(request):
  #df = pd.read_csv(r'E:\mywebsite\ui\myapp\xx.csv')
 
  import random
 
  # dfx = pd.DataFrame()
  # dfx['a'] = ['2017-08-08','2017-08-09','2017-08-10']
  # dfx['b'] = [random.random(),random.random(),random.random()]
  # dfx['c'] = [random.random(),random.random(),random.random()]
  #
  # dfx['a'] = pd.to_datetime(dfx.a)
  #
  # dfx = dfx.set_index('a')
 
 
  import sqlite3
  conn = sqlite3.connect(r"E:\01_Lab\L02_Ads\practise\ads_sample\multi_freq_data\multi_freq_data\bin\x86\Debug\db_all.db")
  df = pd.read_sql('select * from buffer',conn)
  df = df.set_index(pd.to_datetime(df.TimeStamp))
  dfn = pd.DataFrame()
  dfn['ws'] = df.grWindSpeed.astype(float)
 
  dfn = dfn.tail(500)
 
  option = de.eplot(dfn,1)
  str_option = json.dumps(option)
  context = {"myContext": str_option}
 
  #return render(request,'myapp/a.html',context)
  return HttpResponse(str_option)
 
 
def test_ajax(request):
 
  import sqlite3
  conn = sqlite3.connect(r"E:\01_Lab\L02_Ads\practise\ads_sample\multi_freq_data\multi_freq_data\bin\x86\Debug\db_all.db")
  df = pd.read_sql('select * from buffer',conn)
  df = df.set_index(pd.to_datetime(df.TimeStamp))
  dfn = pd.DataFrame()
  dfn['ws'] = df.grWindSpeed.astype(float)
 
  dfn = dfn.tail(500)
 
  option = de.eplot(dfn,1)
  str_option = json.dumps(option)
  context = {"myContext": str_option}
 
 
  #context = {"myContext": {'a':[1,2],'b':[3,4]}}
  return render(request, 'myapp/ajax.html', context)