我想从我的PHP文件传递我的热图层的heatmapdata数组。当运行我的代码(如下)时，我得到以下异常:
Uncaught TypeError: b.lat is not a function
有人知道为什么吗?
. html
<!DOCTYPE html>
<html>
<body>
<form>
<select name="users" onchange="showString(this.value)">
<option value="">WholeWorldAllTime:</option>
<option value="1">Whole World 1 Hour</option>
</select>
</form>
<div id="map"></div>
<script>
function showString(time) {
if (window.XMLHttpRequest) {
xmlhttp=new XMLHttpRequest();
}
xmlhttp.onreadystatechange=function() {
if (xmlhttp.readyState==4 && xmlhttp.status==200) {
var heatmapdata = [xmlhttp.responseText];
var heatmap = new google.maps.visualization.HeatmapLayer({
data: heatmapdata,
map: map
});
}
}
xmlhttp.open("GET","getstring.php?q="+time,true);
xmlhttp.send();
}
</script>
<script>
var map;
function initMap() {
map = new google.maps.Map(document.getElementById('map'), {
zoom: 3,
center: {lat: 37.775, lng: -122.434},
mapTypeId: google.maps.MapTypeId.SATELLITE
});
}
</script>
<script async defer
src="https://maps.googleapis.com/maps/api/js?signed_in=true&libraries=visualization&callback=initMap">
</script>
</body>
</html>
。php
<?php
$q = intval($_GET['q']);
$con = pg_connect("host=localhost port=5432 dbname=Twitter user=postgres password=****");
if (!$con) {
die('Could not connect: ' . pg_errormessage($con));
}
$sql="SELECT * FROM tswholeworld WHERE createdat > (NOW() - INTERVAL '".$q."hour');";
$result = pg_query($con,$sql);
$string = "";
while($row = pg_fetch_assoc($result)){
$lat = $row['latitude'];
$lon = $row['longitude'];
$string .= "new google.maps.LatLng($lat, $lon), ";
}
echo $string;
pg_close($con);
?>
heatmapdata不是google.maps.LatLng对象的数组。
var heatmapdata = [xmlhttp.responseText];
此链接上的HEATMAP代码https://github.com/gauribane/heatmap-in-plain-html.git
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Heatmaps</title>
<style>
/* Always set the map height explicitly to define the size of the div
* element that contains the map. */
#map {
height: 100%;
}
/* Optional: Makes the sample page fill the window. */
html, body {
height: 100%;
margin: 0;
padding: 0;
}
#floating-panel {
position: absolute;
top: 10px;
left: 25%;
z-index: 5;
background-color: #fff;
padding: 5px;
border: 1px solid #999;
text-align: center;
font-family: 'Roboto','sans-serif';
line-height: 30px;
padding-left: 10px;
}
#floating-panel {
background-color: #fff;
border: 1px solid #999;
left: 25%;
padding: 5px;
position: absolute;
top: 10px;
z-index: 5;
}
</style>
</head>
<body>
<div id="floating-panel">
<button onclick="toggleHeatmap()">Toggle Heatmap</button>
<button onclick="changeGradient()">Change gradient</button>
<button onclick="changeRadius()">Change radius</button>
<button onclick="changeOpacity()">Change opacity</button>
</div>
<div id="map"></div>
<script>
// This example requires the Visualization library. Include the libraries=visualization
// parameter when you first load the API. For example:
// <script src="https://maps.googleapis.com/maps/api/js?key=YOUR_API_KEY&libraries=visualization">
var map, heatmap;
function initMap() {
map = new google.maps.Map(document.getElementById('map'), {
zoom: 13,
center: {lat: 37.775, lng: -122.434},
mapTypeId: 'satellite'
});
heatmap = new google.maps.visualization.HeatmapLayer({
data: getPoints(),
map: map
});
}
function toggleHeatmap() {
heatmap.setMap(heatmap.getMap() ? null : map);
}
function changeGradient() {
var gradient = [
'rgba(0, 255, 255, 0)',
'rgba(0, 255, 255, 1)',
'rgba(0, 191, 255, 1)',
'rgba(0, 127, 255, 1)',
'rgba(0, 63, 255, 1)',
'rgba(0, 0, 255, 1)',
'rgba(0, 0, 223, 1)',
'rgba(0, 0, 191, 1)',
'rgba(0, 0, 159, 1)',
'rgba(0, 0, 127, 1)',
'rgba(63, 0, 91, 1)',
'rgba(127, 0, 63, 1)',
'rgba(191, 0, 31, 1)',
'rgba(255, 0, 0, 1)'
]
heatmap.set('gradient', heatmap.get('gradient') ? null : gradient);
}
function changeRadius() {
heatmap.set('radius', heatmap.get('radius') ? null : 20);
}
function changeOpacity() {
heatmap.set('opacity', heatmap.get('opacity') ? null : 0.2);
}
// Heatmap data: 500 Points
function getPoints() {
return [
new google.maps.LatLng(37.782551, -122.445368),
new google.maps.LatLng(37.782745, -122.444586),
new google.maps.LatLng(37.782842, -122.443688),
new google.maps.LatLng(37.782919, -122.442815),
new google.maps.LatLng(37.782992, -122.442112),
new google.maps.LatLng(37.783100, -122.441461),
new google.maps.LatLng(37.783206, -122.440829),
new google.maps.LatLng(37.783273, -122.440324),
new google.maps.LatLng(37.783316, -122.440023),
new google.maps.LatLng(37.783357, -122.439794),
new google.maps.LatLng(37.783371, -122.439687),
new google.maps.LatLng(37.783368, -122.439666),
new google.maps.LatLng(37.783383, -122.439594),
new google.maps.LatLng(37.783508, -122.439525),
new google.maps.LatLng(37.783842, -122.439591),
new google.maps.LatLng(37.784147, -122.439668),
new google.maps.LatLng(37.784206, -122.439686),
new google.maps.LatLng(37.784386, -122.439790),
new google.maps.LatLng(37.784701, -122.439902),
new google.maps.LatLng(37.784965, -122.439938),
new google.maps.LatLng(37.785010, -122.439947),
new google.maps.LatLng(37.785360, -122.439952),
new google.maps.LatLng(37.785715, -122.440030),
new google.maps.LatLng(37.786117, -122.440119),
new google.maps.LatLng(37.786564, -122.440209),
new google.maps.LatLng(37.786905, -122.440270),
new google.maps.LatLng(37.786956, -122.440279),
new google.maps.LatLng(37.800224, -122.433520),
new google.maps.LatLng(37.800155, -122.434101),
new google.maps.LatLng(37.800160, -122.434430),
new google.maps.LatLng(37.800378, -122.434527),
new google.maps.LatLng(37.800738, -122.434598),
new google.maps.LatLng(37.800938, -122.434650),
new google.maps.LatLng(37.801024, -122.434889),
new google.maps.LatLng(37.800955, -122.435392),
new google.maps.LatLng(37.800886, -122.435959),
new google.maps.LatLng(37.800811, -122.436275),
new google.maps.LatLng(37.800788, -122.436299),
new google.maps.LatLng(37.800719, -122.436302),
new google.maps.LatLng(37.800702, -122.436298),
new google.maps.LatLng(37.800661, -122.436273),
new google.maps.LatLng(37.800395, -122.436172),
new google.maps.LatLng(37.800228, -122.436116),
new google.maps.LatLng(37.800169, -122.436130),
new google.maps.LatLng(37.800066, -122.436167),
new google.maps.LatLng(37.784345, -122.422922),
new google.maps.LatLng(37.784389, -122.422926),
new google.maps.LatLng(37.784437, -122.422924),
new google.maps.LatLng(37.784746, -122.422818),
new google.maps.LatLng(37.785436, -122.422959),
new google.maps.LatLng(37.786120, -122.423112),
new google.maps.LatLng(37.786433, -122.423029),
new google.maps.LatLng(37.786631, -122.421213),
new google.maps.LatLng(37.786660, -122.421033),
new google.maps.LatLng(37.786801, -122.420141),
new google.maps.LatLng(37.786823, -122.420034),
new google.maps.LatLng(37.786831, -122.419916),
new google.maps.LatLng(37.787034, -122.418208),
new google.maps.LatLng(37.787056, -122.418034),
new google.maps.LatLng(37.787169, -122.417145),
new google.maps.LatLng(37.787217, -122.416715),
new google.maps.LatLng(37.786144, -122.416403),
new google.maps.LatLng(37.785292, -122.416257),
new google.maps.LatLng(37.780666, -122.390374),
new google.maps.LatLng(37.780501, -122.391281),
new google.maps.LatLng(37.780148, -122.392052),
new google.maps.LatLng(37.780173, -122.391148),
new google.maps.LatLng(37.780693, -122.390592),
new google.maps.LatLng(37.781261, -122.391142),
new google.maps.LatLng(37.781808, -122.391730),
new google.maps.LatLng(37.782340, -122.392341),
new google.maps.LatLng(37.782812, -122.393022),
new google.maps.LatLng(37.783300, -122.393672),
new google.maps.LatLng(37.783809, -122.394275),
new google.maps.LatLng(37.784246, -122.394979),
new google.maps.LatLng(37.784791, -122.395958),
new google.maps.LatLng(37.785675, -122.396746),
new google.maps.LatLng(37.786262, -122.395780),
new google.maps.LatLng(37.786776, -122.395093),
new google.maps.LatLng(37.787282, -122.394426),
new google.maps.LatLng(37.787783, -122.393767),
new google.maps.LatLng(37.788343, -122.393184),
new google.maps.LatLng(37.788895, -122.392506),
new google.maps.LatLng(37.789371, -122.391701),
new google.maps.LatLng(37.789722, -122.390952),
new google.maps.LatLng(37.790315, -122.390305),
new google.maps.LatLng(37.790738, -122.389616),
new google.maps.LatLng(37.779448, -122.438702),
new google.maps.LatLng(37.779023, -122.438585),
new google.maps.LatLng(37.778542, -122.438492),
new google.maps.LatLng(37.778100, -122.438411),
new google.maps.LatLng(37.777986, -122.438376),
new google.maps.LatLng(37.777680, -122.438313),
new google.maps.LatLng(37.777316, -122.438273),
new google.maps.LatLng(37.777135, -122.438254),
new google.maps.LatLng(37.776987, -122.438303),
new google.maps.LatLng(37.776946, -122.438404),
new google.maps.LatLng(37.776944, -122.438467),
new google.maps.LatLng(37.776892, -122.438459),
new google.maps.LatLng(37.776842, -122.438442),
new google.maps.LatLng(37.776822, -122.438391),
new google.maps.LatLng(37.776814, -122.438412),
new google.maps.LatLng(37.776787, -122.438628),
new google.maps.LatLng(37.776729, -122.438650),
new google.maps.LatLng(37.776759, -122.438677),
new google.maps.LatLng(37.776772, -122.438498),
new google.maps.LatLng(37.776787, -122.438389),
new google.maps.LatLng(37.776848, -122.438283),
new google.maps.LatLng(37.776870, -122.438239),
new google.maps.LatLng(37.777015, -122.438198),
new google.maps.LatLng(37.777333, -122.438256),
new google.maps.LatLng(37.777595, -122.438308),
new google.maps.LatLng(37.777797, -122.438344),
new google.maps.LatLng(37.778160, -122.438442),
new google.maps.LatLng(37.778414, -122.438508),
new google.maps.LatLng(37.778445, -122.438516),
new google.maps.LatLng(37.778503, -122.438529),
new google.maps.LatLng(37.778607, -122.438549),
new google.maps.LatLng(37.778670, -122.438644),
new google.maps.LatLng(37.778847, -122.438706),
new google.maps.LatLng(37.779240, -122.438744),
new google.maps.LatLng(37.779738, -122.438822),
new google.maps.LatLng(37.780201, -122.438882),
new google.maps.LatLng(37.780400, -122.438905),
new google.maps.LatLng(37.780501, -122.438921),
new google.maps.LatLng(37.780892, -122.438986),
new google.maps.LatLng(37.781446, -122.439087),
new google.maps.LatLng(37.781985, -122.439199),
new google.maps.LatLng(37.782239, -122.439249),
new google.maps.LatLng(37.782286, -122.439266),
new google.maps.LatLng(37.797847, -122.429388),
new google.maps.LatLng(37.797874, -122.429180),
new google.maps.LatLng(37.797885, -122.429069),
new google.maps.LatLng(37.797887, -122.429050),
new google.maps.LatLng(37.797933, -122.428954),
new google.maps.LatLng(37.798242, -122.428990),
new google.maps.LatLng(37.798617, -122.429075),
new google.maps.LatLng(37.798719, -122.429092),
new google.maps.LatLng(37.798944, -122.429145),
new google.maps.LatLng(37.799320, -122.429251),
new google.maps.LatLng(37.799590, -122.429309),
new google.maps.LatLng(37.799677, -122.429324),
new google.maps.LatLng(37.799966, -122.429360),
new google.maps.LatLng(37.800288, -122.429430),
new google.maps.LatLng(37.800443, -122.429461),
new google.maps.LatLng(37.800465, -122.429474),
new google.maps.LatLng(37.800644, -122.429540),
new google.maps.LatLng(37.800948, -122.429620),
new google.maps.LatLng(37.801242, -122.429685),
new google.maps.LatLng(37.801375, -122.429702),
new google.maps.LatLng(37.801400, -122.429703),
new google.maps.LatLng(37.801453, -122.429707),
new google.maps.LatLng(37.801473, -122.429709),
new google.maps.LatLng(37.801532, -122.429707),
new google.maps.LatLng(37.801852, -122.429729),
new google.maps.LatLng(37.802173, -122.429789),
new google.maps.LatLng(37.779695, -122.403950),
new google.maps.LatLng(37.779982, -122.403584),
new google.maps.LatLng(37.780295, -122.403223),
new google.maps.LatLng(37.780664, -122.402766),
new google.maps.LatLng(37.781043, -122.402288),
new google.maps.LatLng(37.781399, -122.401823),
new google.maps.LatLng(37.781727, -122.401407),
new google.maps.LatLng(37.781853, -122.401247),
new google.maps.LatLng(37.781894, -122.401195),
new google.maps.LatLng(37.782076, -122.400977),
new google.maps.LatLng(37.782338, -122.400603),
new google.maps.LatLng(37.782666, -122.400133),
new google.maps.LatLng(37.783048, -122.399634),
new google.maps.LatLng(37.783450, -122.399198),
new google.maps.LatLng(37.783791, -122.398998),
new google.maps.LatLng(37.784177, -122.398959),
new google.maps.LatLng(37.784388, -122.398971),
new google.maps.LatLng(37.784404, -122.399128),
new google.maps.LatLng(37.784586, -122.399524),
new google.maps.LatLng(37.784835, -122.399927),
new google.maps.LatLng(37.785116, -122.400307),
new google.maps.LatLng(37.785282, -122.400539),
new google.maps.LatLng(37.785346, -122.400692),
new google.maps.LatLng(37.765769, -122.407201),
new google.maps.LatLng(37.765790, -122.407414),
new google.maps.LatLng(37.765802, -122.407755),
new google.maps.LatLng(37.765791, -122.408219),
new google.maps.LatLng(37.765763, -122.408759),
new google.maps.LatLng(37.765726, -122.409348),
new google.maps.LatLng(37.765716, -122.409882),
new google.maps.LatLng(37.765708, -122.410202),
new google.maps.LatLng(37.765705, -122.410253),
new google.maps.LatLng(37.765707, -122.410369),
new google.maps.LatLng(37.765692, -122.410720),
new google.maps.LatLng(37.765699, -122.411215),
new google.maps.LatLng(37.765687, -122.411789),
new google.maps.LatLng(37.765666, -122.412373),
new google.maps.LatLng(37.765598, -122.412883),
new google.maps.LatLng(37.765543, -122.413039),
new google.maps.LatLng(37.765532, -122.413125),
new google.maps.LatLng(37.765500, -122.413553),
new google.maps.LatLng(37.765448, -122.414053),
new google.maps.LatLng(37.765388, -122.414645),
new google.maps.LatLng(37.765323, -122.415250),
new google.maps.LatLng(37.765303, -122.415847),
new google.maps.LatLng(37.765251, -122.416439),
new google.maps.LatLng(37.765204, -122.417020),
new google.maps.LatLng(37.765172, -122.417556),
new google.maps.LatLng(37.765164, -122.418075),
new google.maps.LatLng(37.765153, -122.418618),
new google.maps.LatLng(37.751266, -122.403355)
];
}
</script>
<script async defer
src="https://maps.googleapis.com/maps/api/js?key=Your google map key">
</script>
</body>
</html>