Simply write an extension method for SQLCommand wrapping the original functionality.
<Extension()>
Public Function MyExecuteScalar(ByVal sqlCommand As SqlCommand) As Boolean
MyExecuteScalar = Not (sqlCommand.ExecuteScalar() is Nothing)
End Function
<Extension()>
Public Function MyExecuteNonQuery(ByVal sqlCommand As SqlCommand) As Boolean
MyExecuteNonQuery = sqlCommand.ExecuteNonQuery() > 0
End Function
Call these methods simply like this:
if mySqlCommand.MyExecutescalar() then ...