How to know if your code is running in the Windows Azure environment

To understand whether the role instance is running in the Windows Azure environment you simply need to check this static variable:

RoleEnvironment.IsAvailable

Namespace: Microsoft.WindowsAzure.ServiceRuntime
Assembly: Microsoft.WindowsAzure.ServiceRuntime (in Microsoft.WindowsAzure.ServiceRuntime.dll)

http://msdn.microsoft.com/en-us/library/microsoft.windowsazure.serviceruntime.roleenvironment.isavailable.aspx