Returning value from function inside a function
I'm using goMap
and I'm trying to add a function inside it, but I cannot get it to return when the function is called. If I use alert()
inside the function, it has the values I need it that should be returned.
getAddress: function(latlngcoords)
{
var goMap = this;
var input = latlngcoords;
var latlngStr = input.split(",", 2);
var lat = parseFloat(latlngStr[0]);
var lng = parseFloat(latlngStr[1]);
var latlng = new google.maps.LatLng(lat, lng);
var address;
geocoder.geocode({'latLng': latlng}, function(results, status)
{
if(statu开发者_运维知识库s == google.maps.GeocoderStatus.OK)
{
if(results)
{
address = results;
//alert(address); <-- works but
}
}
});
return address; // won't return at all?
},
It's called by doing: $.goMap.getAddress()
but with a latitude and longitude in the argument. I need it to return the values by return address
but it won't return anything at all.
How will I be able to get it to return the value?
geocode
is an asynchronous function. It starts when you call it, but that's all. (That's why it accepts a callback.) So your getAddress
function is returning before address
is set by the callback.
You need to have your getAddress
function accept a callback as well, and return the result that way, e.g.
getAddress: function(latlngcoords, callback)
// ^--- callback parameter
{
var goMap = this;
var input = latlngcoords;
var latlngStr = input.split(",", 2);
var lat = parseFloat(latlngStr[0]);
var lng = parseFloat(latlngStr[1]);
var latlng = new google.maps.LatLng(lat, lng);
var address;
geocoder.geocode({'latLng': latlng}, function(results, status)
{
if(status == google.maps.GeocoderStatus.OK)
{
if(results)
{
address = results;
callback(address);
// ^--- call it with the result
}
}
});
},
Naturally this means that the code calling getAddress
has to handle the fact that getAddress
is also asynchronous.
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