Read an entry matching the specified id query from the space.
            Blocks up to the specified timeout (if any) only if a matching entry exists and it is 
            necessary to wait for transactional state to settle.
            
| C# | Visual Basic | Visual C++ | J# | 
T ReadIfExistsById<T>( IdQuery<T> idQuery, ITransaction tx )
Function ReadIfExistsById(Of T) ( _ idQuery As IdQuery(Of T), _ tx As ITransaction _ ) As T
generic<typename T> T ReadIfExistsById( IdQuery<T>^ idQuery, ITransaction^ tx )
- T
 - Type of expected result entry.
 
- idQuery (IdQuery<(Of <(T>)>))
 - The query to search by.
 
- tx (ITransaction)
 - The transaction which this operation will participate in.
 
Result entry from space (null if not found).
