MDL语言是一种结构化编程语言，它让我们生成一个应用程序的标准命令、函数和目标。MDL是这样一种语言，它采用C的结构，具有自己的运行时间库、编译程序、链接程序、库管理程序，并在MicroStation环境下运行。 本书将会结合MicroStation对MDL程序设计进行介绍，将MDL作为一种进入MicroStation内部来开发应用程序的工具。-MDL language is a structured programming language, it allows us to generate a standard application commands, functions and objectives. MDL is such a language, it uses the C structure, with its own run-time libraries, compiler, linker, librarian, and MicroStation environments. This book will be combined with MicroStation MDL application of the design introduced the MDL as a house into MicroStation tools to develop applications.