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Question

我似乎没有找到一个输出我的代码从数据库表中提取2数据和日期，但我似乎没有找到输出..这是我的代码......

data.php：

<script>
AmCharts.loadJSON = function(url) {
  // create the request
  if (window.XMLHttpRequest) {
    // IE7+, Firefox, Chrome, Opera, Safari
    var request = new XMLHttpRequest();
  } else {
    // code for IE6, IE5
    var request = new ActiveXObject('Microsoft.XMLHTTP');
  }

  // load it
  // the last "false" parameter ensures that our code will wait before the
  // data is loaded
  request.open('GET', url, false);
  request.send();

  // parse adn return the output
  return eval(request.responseText);
};
  </script>

  <!-- chart container -->
  <div id="chartdiv" style="width: 600px; height: 300px;"></div>

  <!-- the chart code -->
  <script>
var chart;

// create chart
AmCharts.ready(function() {

  // load the data
  var chartData = AmCharts.loadJSON('data.php');

  // SERIAL CHART
  chart = new AmCharts.AmSerialChart();
  chart.pathToImages = "http://www.amcharts.com/lib/images/";
  chart.dataProvider = chartData;
  chart.categoryField = "date";
  chart.dataDateFormat = "YYYY-MM-DD";

  // GRAPHS

  var graph1 = new AmCharts.AmGraph();
  graph1.valueField = "km_per_lit";
  graph1.bullet = "round";
  graph1.bulletBorderColor = "#000000";
  graph1.bulletBorderThickness = 2;
 graph1.lineThickness = 2;
  graph1.lineAlpha = 0.5;
  chart.addGraph(graph1);

  var graph2 = new AmCharts.AmGraph();
  graph2.valueField = "Longterm_KM_Liter";
  graph2.bullet = "round";
  graph2.bulletBorderColor = "#000000";
  graph2.bulletBorderThickness = 2;
  graph2.lineThickness = 2;
  graph2.lineAlpha = 0.5;
  chart.addGraph(graph2);

  // CATEGORY AXIS
  chart.categoryAxis.parseDates = true;

  // WRITE
  chart.write("chartdiv");
});