var map;
function initMap() {
var opts = {
zoom: 15,
center: new google.maps.LatLng(35.185384,136.89909)
};
map = new google.maps.Map(document.getElementById("map"), opts);
map.addListener('drag', dispLatLng);
}
function dispLatLng(){
var latlng = map.getCenter();
var str = "中心:" + latlng.lat() + "," + latlng.lng() + "
";
var latlngBounds = map.getBounds();
var swLatlng = latlngBounds.getSouthWest();
str = str + "左下:" + swLatlng.lat() + "," + swLatlng.lng() + "
";
var neLatlng = latlngBounds.getNorthEast();
str = str + "右上:" + neLatlng.lat() + "," + neLatlng.lng();
document.getElementById("latlng").innerHTML = str;
}