Skip to main content

Be careful of the culture when using Bing Maps REST API

When developing the Bing Maps Wrapper service for the WP7Contrib we weren't aware of the importance of the instance of the CultureInfo class used to format the geo-coordinate data when building the URL parameters.

This was for the simple reason, being based in the UK we were relying on the default culture, which happens to be 'en-US'  and this culture formats decimal numbers in the required format for calls to the Bing Maps REST API. The documentation on MSDN does state this, but does not make it very clear.

Show below is the formatting for a couple of different cultures, what you'll see is the formatting for the Lat & Long for the Netherlands & Russian cultures is different to the rest. They both use commas as the decimal point.

When the Lat & Long are used to format the URL parameter they need to be in InvariantCulture so that your URL looks like the following:

If I force the Bing Maps Service to use the Netherlands culture with the code shown below (taken from inside the service class):

Then I get the following output in visual studio; What's interesting is the Bing Maps server doesn't return an error code (it still returns a status code of 200) even though the location data is formatted incorrectly. This is why I have added the boolean checks 'HasSucceeded' & 'HasLocations' to the result class.

So now when formatting floating point numbers for use with the Bings Maps API we use the following style inside the Bing Maps Wrapper service:

Thanks to Derek Lakin for pointing this one out, you can see multi-culture Bing Maps REST API requests being used in his WP7 app 'Car Finder'.


Popular posts from this blog

Showing a message box from a ViewModel in MVVM

I was doing a code review with a client last week for a WPF app using MVVM and they asked ' How can I show a message from the ViewModel? '. What follows is how I would (and have) solved the problem in the past. When I hear the words ' show a message... ' I instantly think you mean show a transient modal message box that requires the user input before continuing ' with something else ' - once the user has interacted with the message box it will disappear. The following solution only applies to this scenario. The first solution is the easiest but is very wrong from a separation perspective. It violates the ideas behind the Model-View-Controller pattern because it places View concerns inside the ViewModel - the ViewModel now knows about the type of the View and specifically it knows how to show a message box window: The second approach addresses this concern by introducing the idea of messaging\events between the ViewModel and the View. In the example below

Implementing a busy indicator using a visual overlay in MVVM

This is a technique we use at work to lock the UI whilst some long running process is happening - preventing the user clicking on stuff whilst it's retrieving or rendering data. Now we could have done this by launching a child dialog window but that feels rather out of date and clumsy, we wanted a more modern pattern similar to the way <div> overlays are done on the web. Imagine we have the following simple WPF app and when 'Click' is pressed a busy waiting overlay is shown for the duration entered into the text box. What I'm interested in here is not the actual UI element of the busy indicator but how I go about getting this to show & hide from when using MVVM. The actual UI elements are the standard Busy Indicator coming from the WPF Toolkit : The XAML behind this window is very simple, the important part is the ViewHost. As you can see the ViewHost uses a ContentPresenter element which is bound to the view model, IMainViewModel, it contains 3 child v

Custom AuthorizationHandler for SignalR Hubs

How to implement IAuthorizationRequirement for SignalR in Asp.Net Core v5.0 Been battling this for a couple of days, and eventually ended up raising an issue on Asp.Net Core gitHub  to find the answer. Wanting to do some custom authorization on a SignalR Hub when the client makes a connection (Hub is created) and when an endpoint (Hub method) is called:  I was assuming I could use the same Policy for both class & method attributes, but it ain't so - not because you can't, because you need the signatures to be different. Method implementation has a resource type of HubInnovationContext: I assumed class implementation would have a resource type of HubConnectionContext - client connects etc... This isn't the case, it's infact of type DefaultHttpContext . For me I don't even need that, it can be removed completely  from the inheritence signature and override implementation. Only other thing to note, and this could be a biggy, is the ordering of the statements in th