We present a new approach to handle the data exchange between application programs in performing coupled micro-electro-mechanical system (MEMS) simulation. With existing techniques, input data is extracted via a close interaction between each application program and a parser, which performs pattern matching and possibly executes semantic actions. Such a strong coupling application-parser interaction makes it problematic for handling, filtering, and exchanging input data among different application programs. This also makes it difficult to automatically generate code for extractors of input data. To tackle the above issues, we have developed a novel method to abstractly represent input data as an object-oriented data structure with read/write facilities. The data structure together with its internal implementation is program-generated, thus eliminating both the need for writing or generating parsers or directly manipulating the parse trees. All reading and writing of data is made via this object-oriented interface. The new technique enables the handling of input and output data in a systematic and object-oriented manner, opening new possibilities for extracting input data of coupled MEMS simulation, and in general, engineering and scientific applications.