我正试图从数据库中获取数据，并将其传递给javascript，以便在谷歌地图上显示为标记。当我使用javascript var标记变量时，它工作得很好，但当我试图获取数据库数据，将其传递给数组，对其进行编码并在javascript中使用时，它会产生这个不清楚的错误错误(；
$coordinates = array(); // Select all the rows in the markers table
$query = "SELECT `locationLatitude`, `locationLongitude`,'ID' FROM `location_tab` ";
$result = $mysqli->query($query) or die('data selection for google map failed: ' . $mysqli->error);
while ($row = mysqli_fetch_array($result)) {
$latitudes = $row['locationLatitude'];
$longitudes = $row['locationLongitude'];
$ID= $row['ID'];
$coordinates[]= array('id'=>$ID,'lat'=>$latitudes,'lng'=>$longitudes );
print_r($coordinates);
}
$markerss= json_encode($coordinates);
?>
这是我的代码
<?php
/* Database connection settings */
$host = 'localhost';
$user = 'root';
$pass = '';
$db = 'location_db';
$mysqli = new mysqli($host,$user,$pass,$db) or die($mysqli->error);
$coordinates = array();
// Select all the rows in the markers table
$query = "SELECT `locationLatitude`, `locationLongitude`,'ID' FROM
`location_tab` ";
$result = $mysqli->query($query) or die('data selection for google map
failed: ' . $mysqli->error);
while ($row = mysqli_fetch_array($result)) {
$latitudes = $row['locationLatitude'];
$longitudes = $row['locationLongitude'];
$ID= $row['ID'];
$coordinates[]= array('id'=>$ID,'lat'=>$latitudes,'lng'=>$longitudes );
}
$markerss= json_encode($coordinates);
?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" />
<title>Add Google Map with multiple markers to your website</title>
<style>
body { font-family:Arial, Helvetica, sans-serif; font-size:14px; }
h1 { clear:both; margin-bottom:30px; font-size:17px; }
h1 a { font-weight:bold; color:#0099FF; }
span { clear:both; display:block; margin-bottom:30px; }
span a { font-weight:bold; color:#0099FF; }
#google_map { width:100%; height:500px; border:1px dashed #000; }
</style>
</head>
<body>
<div class="contentDiv">
<div id="google_map"></div>
</div><!-- end of .contentDiv -->
<script type="text/jscript">
function initiateGoogleMap() {
//Some properties we want to pass to the map
var options = {
mapTypeId: google.maps.MapTypeId.ROADMAP //All map types are --
ROADMAP/SATELLITE/HYBRID/TERRAIN
};
//Initializing the map
var map = new google.maps.Map(document.getElementById('google_map'),
options);
//map.setTilt(45);
//google maps data from database
<?php
echo "var markerss=$markerss;n";
?>
//Multiple Markers
var markers = [
['CAD-CAM Robotics Lab, Mechanical Engineering Department', 22.318861,
87.312747],
['Technology Guest House', 22.315967, 87.303832],
['Visveswaraya Guest House', 22.314685, 87.305177],
['G S Sanyal School of Telecommunications(GSST)', 22.317067,
87.312221],
['Technology Market', 22.314625, 87.300049],
['Central Research Facility', 22.320527, 87.313855],
['Naval Architecture Department', 22.320745, 87.314929],
['Central Library', 22.320189, 87.309660],
['School of Medical Science & Technology', 22.315848, 87.310758],
['Mining Department', 22.321509, 87.311274]
];
//Info Contents
var infoContents = [
["CAD-CAM Robotics Lab", "CAD-CAM Robotics Lab, Mechanical Engineering
Department, Indian Institute of Technology Kharagpur, India"],
["Technology Guest House", "Technology Guest House, Indian Institute
of Technology Kharagpur, India"],
["Visveswaraya Guest House", "Visveswaraya Guest House, Indian
Institute of Technology Kharagpur, India"],
["G S Sanyal School of Telecommunications(GSST)", "G S Sanyal School
of Telecommunications(GSST), Indian Institute of Technology Kharagpur,
India"],
["Technology Market", "Technology Market, Indian Institute of
Technology Kharagpur, India"],
["Central Research Facility", "Central Research Facility, Indian
Institute of Technology Kharagpur, India"],
["Naval Architecture Department", "Naval Architecture Department,
Indian Institute of Technology Kharagpur, India"],
["Central Library", "Central Library, Indian Institute of Technology
Kharagpur, India"],
["School of Medical Science & Technology", "School of Medical Science
& Technology, Indian Institute of Technology Kharagpur, India"],
["Mining Department", "Mining Department, Indian Institute of
Technology Kharagpur, India"],
];
var bounds = new google.maps.LatLngBounds();
//Create an object of InfoWindow class
var infoWindow = new google.maps.InfoWindow();
var marker, i;
// Loop through markers array and place each marker on the map
for(i=0; i<markerss.length; i++) {
var marker_position = new google.maps.LatLng(markerss[i][1],
markerss[i][2]);
bounds.extend(marker_position);
marker = new google.maps.Marker({
position: marker_position,
map: map,
title: markerss[i][0]
});
//Assign each marker an info window, which will display in click event
google.maps.event.addListener(marker, 'click', (function(marker, i) {
return function() {
infoWindow.setContent('<strong>'+infoContents[i][0]+'</strong>
<br/><br/>'+infoContents[i][1]);
infoWindow.open(map, marker);
}
})(marker, i));
//Automatically center the map, so that all markers fit on the screen
map.fitBounds(bounds);
}
//Override zoom level of the map
var boundsListener = google.maps.event.addListener((map), 'bounds_changed',
function(event) {
this.setZoom(15);
google.maps.event.removeListener(boundsListener);
});
}
</script>
<script async defer src="https://maps.googleapis.com/maps/api/js?
key=AIzaSyC-dFHYjTqEVLndbN2gdvXsx09jfJHmNc8&callback=initiateGoogleMap">
</script>
</body>
</html>
替换中的以下代码。
//google maps data from database
<?php
echo "var markerss=$markerss;n";
?>
至
//google maps data from database
var markerss = <?php echo $markerss; ?>
您有一个没有别名的字符串"ID"，这会为$rows数组中的无效索引产生错误(可能是您试图选择列ID，但错误地添加了单引号，然后更改select locationLatitude，locationLongitude，"ID"AS ID带SELECT locationLatitude、locationLongitude、ID(
<?php
$coordinates = array();
// Select all the rows in the markers table
$query = "SELECT locationLatitude, locationLongitude, 'ID' AS ID FROM location_tab ";
$result = $mysqli->query($query) or die('data selection for google map failed: ' . $mysqli->error);
while ($row = mysqli_fetch_array($result)) {
$latitudes = $row['locationLatitude'];
$longitudes = $row['locationLongitude'];
$ID= $row['ID'];
$coordinates[]= array('id'=>$ID,'lat'=>$latitudes,'lng'=>$longitudes );
print_r($coordinates);
}
$markerss= json_encode($coordinates);
?>
并且在您的javascript中使用
var markerss= <?= $markerss; . ';n' ?>