C++

A lot of times we copy an object instance A to instance B, and when we do something with instance B, we modify instance B to make sure that the modification to B does not affect the normal use of a, you need to use a deep copy. I found some deep

Objective In the process of programming the algorithm, we often need to use random numbers. Since the computer is a logically based machine, it is impossible to do a real random (probably quantum computer?). ）。 So the computer generates pseudo

Recently encountered a need to implement export PDF file, the Internet to check the following code summary of the code, you can successfully export PDF file. You need to download a itextsharp.dll on the web before coding, this assembly is a must.

to developWebVersion of the card reader program, the general idea is as follows: 1. use C # to encapsulate the original DLL , here to encapsulate two parts of the content, part of the function of serial communication, part of the card read and write

First, fork introductory knowledgea process that includes code, data, and resources assigned to the process. The fork () function creates a process that is almost exactly the same as the original process through system calls, where two processes can

The Right value reference (and its supported move semantics and perfect forwarding) is one of the most significant language features that c++0x will join, which can be seen from the list of the features in the C + + state of the evolution. from a

The basic idea of exception handlingThe basic idea of the exception handling of C + + can be summarized as the traditional error handling mechanism and the function return value to handle the error. 1 The exception handling mechanism of C + +

In some cases, it is more convenient to grant member-level access to functions that are not members of a class or to all functions in a separate class. Class-only implementations can declare their friends. A function or class cannot declare itself

Name: sscanf ()-Reads data from a string that matches the specified format. Copy Code code as follows: Function Prototypes: Int sscanf (String str, String fmt, mixed var1, mixed var2 ...);int scanf (const char *format [,

C language character input and output The input/output model provided by the standard library is very simple. Regardless of where the text is entered and where it is exported, its input/output is handled in the same way as a stream of characters.

To learn more about the role and usage of the static keyword in Java, please click here for more information. In C, the literal meaning of static is easy to lead us astray, in fact, it has a role of three, respectively: One is the hidden function,

The concept of C + + arraysIn a nutshell, an array is a collection of ordered data. To find an element in an array, you must give two elements, namely the array name and subscript. The array name and subscript uniquely identify an element in an

A class can have members of public, protected, private three attributes that can access public members through objects, and only functions in this class can access private members of this class. Now, let's add an exception--friend. Fnend means a

Input and output of C + + character arrayThe input and output of a character array can be two ways:1) input and output characters. 2 input or output the whole string one at a time. For example, the following program segments are available:

C language Utime () function: Modify file access time and change timeheader file: #include #include To define a function: int utime (const char * filename, struct utimbuf * buf); Function Description: Utime () is used

C language Rename () function: Renaming a file or directoryheader file: #include The function rename () is used to rename the file, change the file path, or change the directory name, which is a prototype int rename (char *

Digression: Recently in writing an important program, want to do more flexible, so want to take the form of a dialog box, as shown in the figure But several major departments of the C + + and MFC books, there are many online data, this aspect of

Overloads of the new, delete (new[), delete[] operators require attention: 1. The overloaded new, delete (or new[], delete[) operator must be a static member function of the class (why it must be a static member function, which is well understood

Classification function, where the function library is ctype.h int isalpha (int ch) If CH is a letter (' A '-' Z ', ' a '-' Z ') returns a value other than 0, otherwise returns 0 int isalnum (int ch) returns 0 if CH is a letter (' A '-' Z ', ' a '-

"C + + Primer" Part II: C + + standard libraryObjectiveRead the "C + + Primer" Reading a series of notes. This article is part II of the C + + standard library, including the 8th to 12th chapter of the book The Difficult points: IO Library