Library, standard library, API

Transfer

The process of learning a language to application programming can be divided into three steps: 1. Learning the syntax, standard library, and idea of a language; 2. Learning the APIs of relevant operating systems (applications)ProgramProgramming Interface); 3. Use the learning class library. After some experience, the three can alternate and deepen each other. In addition, we need to learn some basic theories, such as the design model,AlgorithmAnd data structure.

Appendix: several other common concepts-Answer: neverdown1983
Q: What is the difference between a standard library and a class library? Can I explain the application programming interface (API? Thank you!

I 'd like to talk about the library first. You may have some knowledge about this concept. Let's say a few more times: the Library is a lot of programs. Code A set of: there are many common functions during programming. If every program that uses these functions needs to be written from the beginning, there will be unnecessary repetitive work; therefore, people have compiled these common functions and organized and encapsulated them according to certain logical relationships, so that they can be called directly during programming and become a library.
How are program modules placed in the library?
Well, first of all, we will naturally think of encapsulating those common functions into corresponding functions, so that when the program needs to use these functions, we will call the corresponding functions. A library composed of these functions can naturally be called a function library. Obviously, the idea of the function library is process-oriented;
Secondly, we can encapsulate the tasks to be implemented into classes. For example, if you want a library to include the file operation function, the designer may write a file class, it may have methods such as open, close, reset, read and write, and some internal data structures that save file information. These libraries are called class libraries and are object-oriented.
Therefore, databases can be divided into function libraries and class libraries according to organizational thinking.
Standard and non-standard databases are another classification method. If a library is required by the C ++ language standard, such as STL (standard template library, containers and Related algorithms, such as vector and list, which are commonly used in C ++, are part of STL, it is called the C ++ standard library (standardized, No matter VC, C ++ builder or other C ++ compiling platforms, it must be included to be "true" C ++ ). Of course, the scope of the standard library is relatively narrow, and other software vendors (or organizations) such as MFC, VCL, and QT write their own libraries, it is not specified by the C ++ standard (books that simply introduce C ++ will not introduce them). It is not part of the language, so it is not a standard library.
Application Programming Interface is a function provided by the operating system for programmers. You need to write a program on an operating system, and every action depends on the operating system: You need to read a file or draw a dot on the screen, in the end, the operating system is required to implement it for you, and these "requirements" methods, or "Dealing with the operating system" methods, are implemented through programming interfaces. In dos, the function implemented by the programmer is ultimately "tell" the Operating System by Means of interruption, so that it can be completed for you. Therefore, it can be said that the interruption is the dossystem API; in a more complex Windows system, interruptions are too simple and low-level, so Windows provides programmers with a series of functions that have been compiled, mostly installed along with the system. in the DLL file, in most cases, the compiler in Windows will link our program to these function libraries. Naturally, they are called API functions. Windows has thousands of API functions, which are much more complex than dozens of interruptions in the DOS area, providing more and more perfect services than DOS. However, it is impossible to remember the names, call methods, and parameters of these functions clearly when learning. Generally, you can have a rough understanding of some of the most commonly used functions; others are generally on-demand queries. In this regard, msdn is a very good (and probably the most authoritative) data set.

 

Source: http://blog.sina.com.cn/s/blog_7957a2be0100s25j.html