C ++ int, Char, String, cstring type conversion

# Include <string> // when using the string class of the C ++ standard library

Using namespace STD; // same as above

# Include <sstream>

# Include <iostream>

# Include <stdlib. h> // it is best to directly convert string and INT types to include,

// Because it is easier to write a conversion function by yourself, the function definition is as follows:

String getstring (const int N)

{

STD: stringstream newstr;
Newstr <N;
Return newstr. STR ();

}

String to cstring
Cstring. Format ("% s", String. c_str ());

C_str () is indeed better than data.

Convert Char to cstring
Cstring. Format ("% s", char *);

Char to string
String S (char *);//Only Initialization is allowed. It is best to use assign () instead of initialization ().

String to char *
Char * P = string. c_str ();

Cstring to string
String S (cstring. getbuffer ());//Releasebuffer () is required after getbuffer (). Otherwise, no space occupied by the buffer is released.

The C ++ standard function library contains three functions that can convert the content of a string to a character array and a C-string.
1. Data (), returns a string array without "\ 0"
2, c_str (), returns a string array with "\ 0"
3, copy ()

Converts a character to an integer. You can use atoi, _ atoi64, or atol.

Cstring Ss = "1212.12 ″;
Int temp = atoi (SS );

Convert a number to a cstring variable. You can use the format function of cstring.For example
Cstring S;
Int I = 64;
S. Format ("% d", I)
The format function is very powerful and worth studying.

Conversion between cstring and char *

/// Char * To cstring
Cstring strtest;
Char * charpoint;
Charpoint = "give string a value ";
Strtest = charpoint;

/// Cstring to char *
Charpoint = strtest. getbuffer (strtest. getlength ());

There is no string in Standard C, char * = char [] = string

You can use the cstring. Format ("% s", char *) method to convert char * To cstring. To convert cstring to char *, use the operator (lpcstr) cstring.

Cstring conversion char [100]

Char A [100];
Cstring STR ("aaaaaa ");
Strncpy (A, (lpctstr) STR, sizeof ());