将JSON数据从PHP数组传递到ChartJS

Question

So I have a PHP array created from data pulled from Advanced Custom Fields in WordPress:

<?php
  $chartArray = array();
  forEach($cat_meta as $key => $value) {
  $chartArray[] = array($value['star_rating']);
  }
  echo json_encode($chartArray);
?>

This outputs the following on the page:

[["2"],["4"],["1"],["3"],["5"]]

What I'm trying to do is get that result into the data variable of the ChartJS file:

var radarChartData = {
labels: ["Price", "Speed", "Format", "Size", "User Experience"],
datasets: [
    {
        label: "My First dataset",
        fillColor: "rgba(220,220,220,0.2)",
        strokeColor: "rgba(224,07,19,1)",
        pointColor: "rgba(224,07,19,1)",
        pointStrokeColor: "#fff",
        pointHighlightFill: "#fff",
        pointHighlightStroke: "rgba(224,07,19,1)",
        data: [5, 4, 5, 5, 1, 3] // data needs to replace this
    }
]
};

var ctx = document.getElementById('RadarChart').getContext('2d');
var myRadarChart = new Chart(ctx).Radar(radarChartData);

I am a bit of a PHP / Javascript n00b so I'm hoping someone might be able to shed some light on this for me. Or maybe there is a better way of doing this? Thank you in advance.

Answer 1

Store the JS object/data from the array as a string in PHP and print it.

<?php

// start script
$str = '<script>';
// start chart
$str .= 'var radarChartData = {';
// make labels
$str .= 'labels: [';
$delimiter = '';
foreach($chartArray as $key => $val){
    $str .= $delimiter.'"'.$key.'"';
    $delimiter = ', ';
}
// make dataset
$str .= '], datasets: [{';
$str .= 'label: "My First dataset", ';
$str .= 'fillColor: "rgba(220,220,220,0.2)", ';
$str .= 'strokeColor: "rgba(224,07,19,1)", ';
$str .= 'pointColor: "rgba(224,07,19,1)", ';
$str .= 'pointStrokeColor: "#fff", ';
$str .= 'pointHighlightFill: "#fff", ';
$str .= 'pointHighlightStroke: "rgba(224,07,19,1)",';
$str .= 'data: [';
$delimiter = '';
foreach($chartArray as $key => $val){
    $str .= $delimiter.$val;
    $delimiter = ', ';
}
$str .= ']}]};';
// end script
$str .= "</script>";
// print
print $str;

?>

<canvas id='RadarChart' class='chart' width='400px' height='400px'></canvas>

<script>
var ctx = document.getElementById('RadarChart').getContext('2d');
var polar_big5 = new Chart(ctx).Radar(radarChartData);
</script>