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This article mainly introduces "how to use string object to deal with file names". In daily operation, I believe many people have doubts about how to use string objects to deal with file names. Xiaobian consulted all kinds of materials and sorted out simple and easy-to-use methods of operation. I hope it will be helpful for you to answer the doubts about "how to use string objects to deal with file names". Next, please follow the editor to study!

C style string

String support has been implemented since the C language. To handle C-style strings, the C language standard library provides a set of functions defined in the cstring.h header file:

Strlen (p) calculates the length of the string

Strcmp (p1, p2) string comparison

Strcat (p1, p2) string concatenation

Strcpy (p1, p2) string comparison

Functionally, C-style strings can fully meet the needs of development. But because a C-style string is actually an array of characters that ends with\ 0. Although this results in string processing becoming one of the skills of C programming, there is no denying that this difficulty can be inconvenient or even dangerous:

1. The memory space for saving strings needs to be managed by programmers and is error-prone.

two。 Almost all processing needs to understand and use the end of\ 0 correctly.

Strings in C++

To solve the above problem, the C++ standard library provides the string class. With the string class, programmers can first (in most cases) ignore the memory allocation of strings, and then they can manipulate strings in a more intuitive way, such as:

Use the = operator to copy a string

String concatenation using the + or + = operator

Use [] to get the specified character from the string

Compare strings using the comparison operator

File names in the C++ standard library

Returning to today's topic, the C++ Standard Library defines three classes to support file reading and writing:

Ifstream: supports reading data from files

Ofstream: supports writing data to files

Fstream: supports reading and writing data.

For some reason, C++ advocates avoiding C-style strings and continuing to use C-style strings instead of string classes when expressing file names in its own standard library. For example, the ifstream::open method:

Void open (const char* filename

Ios_base::openmode mode = ios_base::in)

This situation has changed with Clipper 11, and in addition to supporting the above approach, the following methods can also be used:

Void open (const string& filename

Ios_base::openmode mode = ios_base::in)

The filename parameter in the open file method adds support for the string class. Although this is only the example of ifstream::open, this change also applies to several other file manipulation classes.

At this point, the study on "how to use string objects to handle file names" is over. I hope to be able to solve your doubts. The collocation of theory and practice can better help you learn, go and try it! If you want to continue to learn more related knowledge, please continue to follow the website, the editor will continue to work hard to bring you more practical articles!

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