Excerpted from "Delphi programming university tutorial (Liu Yi, Machinery Industry Press 2005)
http://www.liu-yi.net/bbs/dispbbs.asp?boardid=6&id=300&page=1
Computer programming is both a complicated, knowledgeable theoretical class, and a practical course for actual combat, need to work. Almost all beginner programmers have dreamed that they can gallop in the computer on a week, let a line program constantly flow from the sources of the hand of the keyboard, really become the owner of the computer. However, after learning the programming course, when you really start writing programs, it often feels hard to get it, we have an obey. Although he is studying hard, high scores through the exam, but do not experience the convenience and advantage of the knowledge you have learned to actual programming.
Why is this? One reason is that our students do not have the general process of programming when they study, and have no in-depth understanding of the essential law of general program design language. On the other hand, our teaching system is rigid, the textbook is old, teaching thoughts and content cannot be developed with the actual situation of the software development.
Computer programming language is an artificial language that implements computer operations and control, but programming languages are only the means and pathways of programming, not all programming. Therefore, mastering the programming language does not mean that excellent procedures can be written in the design of proficiency. In fact, the fields involved in the program design, knowledge and skills are far more than our imagination. Therefore, this textbook has its own different understandings for programming courses:
Programming is first is a process program design process. It is usually divided into four stages of problem modeling, algorithm design, writing code, and compiling commissioning. The task of different stages is relatively independent, can't be mixed. Even a relatively simple program, we should also develop a first analysis, then start, finally debug habits, strictly follow the programming process. Because in the absence of problems in depth and comprehensive analysis, the risks will be increased, which will increase the risk of failure, bringing the trouble of post-modification and maintenance. Therefore, learning program is designed, not only cannot avoid the programming process, but also from the software development process and software lifecycle to understand and master the program design process, from the beginning, it is necessary to develop a good habit of compliance with procedure design guidelines. It is different from other procedures to design textbooks, this book emphasizes the importance of program design and software development process, and introduces the basic principles and techniques of software modeling and testing for readers. Special considering that modern software rely on collective cooperation and project management, it is a larger process for many programming processes. Therefore, in addition to the introduction of the software process implementation and management in the book, how to write a specification is as an important section, so that the reader understands the standardization of the program design, pays attention to writing procedures. Sex, correctness, and * are important for cultivating the division of labor cooperation team members involved in large software development.
Programming is still a way to solve the problem and the ability learning program is mainly to teach the method of thinking with computer solutions, cultivating programming applications, rather than just learning a syntax rules for a programming language. Many students can figure out the circulation, IF-ELSE structure, and arithmetic expressions, but it is difficult to break a programming problem into a well-structured Delphi program. This exposes the details of the programs in programming teaching, ignore the overall thought methods and overall process realization.
Although the development of program design theory provides a lot of effective ways to solve problems, it is a way to grasp the most core ideas for beginners: the structure and object-oriented methods. To achieve this, we analyze the focus of structured algorithm as a teaching material, and also focus on object-oriented analysis and design. For the former, we explain the common structured algorithm based on the three basic structures of sequential structure, selection structure, and loop structure; for the latter, we surround object-oriented abstraction, inheritance, polymorphism and encapsulation These four essential features explain the basic methods of object-oriented programming. By emphasizing basic concepts, basic methods, basic applications, we will establish a solid programming foundation for beginners to establish a good programming idea. Through a large number of instance analysis and example program design process demonstrations, we strive to create a complete impression to the beginners, and cultivate its programming capabilities from the whole to grasp problems and solve problems. Programming is ultimately a fun dialectical relationship for application design and programming languages for programming languages. Programming can be implemented in different programming languages, but different programming languages determine what kind of programming ideas and methods can be used, restrict the implementation of programming, and efficiency. This book uses Delphi as a language of learning programming, not because Delphi has a strong visual programming function, but because Delphi not only inherits the perfect structured style of Pascal language, but also has a true advantage of object-oriented language. More gratifying is that Delphi is still developing and constantly absorbs the essence of modern programming languages. All this makes Delphi as representatives of modern general program design languages, especially suitable for teaching. So learning the Delphi language, master the Delphi program design method is another important task in this course.
Although this book introduces the relevant knowledge of programming language in Delphi language, it is important to emphasize some general ideological methods, and give up some of Delphi's oddies. Readers should notice that different programming languages have different grammar and style, but no matter which language is based on data (type), operation (operation), control (logic flow) as the basic content. Furthermore, learn a programming language, it should surpass the specific expression format of the language, not to be stunned in the whistlemony, but stand in an abstract height, master the basic concept of the program design, and understand the essence of the programming language. law. This will bring convenience to in-depth learning of other programming languages.
