我想先说一下:我对 JavaScript 很陌生。我正在尝试使用 Leaflet 和 AJAX 调用来发布用户位置和地图边界。在我的事件处理程序中stateUpdater.onLocationFound
日志语句打印出正确的用户坐标和地图边界,但是我得到Uncaught TypeError: Cannot read property 'lat' of undefined
当尝试序列化这些值时$.param()
。我正在使用 Leaflet v0.7.2 和 jQuery 1.11.0。
var map;
$(document).ready(function() {
map = new L.map('map').setView([41.52, -71.09], 11);
L.tileLayer('http://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png', {
maxZoom: 18
}).addTo(map);
map.on('locationfound', stateUpdater.onLocationFound);
stateUpdater.poll();
});
var stateUpdater = {
errorSleepTime: 10000,
poll: function() {
map.locate({setView: true, maxZoom: 18});
},
onLocationFound: function(e) {
//This log statement produces the correct output
console.log(e.latlng.toString());
var bounds = map.getBounds();
//As does this one
console.log(bounds.toBBoxString())
var args = {
"map_ne": bounds.getNorthEast(),
"map_sw": bounds.getSouthWest(),
"user_coords": e.latLng
};
//Uncaught TypeError thrown here
$.ajax({url: "/a/state/updates", type: "POST", dataType: "text",
data: $.param(args),
success: stateUpdater.onSuccess,
error: stateUpdater.onError});
},
onSuccess: function(response) {
console.log(response);
stateUpdater.errorSleepTime = 10000;
window.setTimeout(stateUpdater.poll, 10000);
},
onError: function(response) {
stateUpdater.errorSleepTime *= 2;
console.log("Poll error; sleeping for", stateUpdater.errorSleepTime, "ms");
window.setTimeout(stateUpdater.poll, stateUpdater.errorSleepTime);
},
};
我对可能导致此问题的原因不再有任何预感,因此我将非常感谢您的帮助。