C++字符串转数字,数字转字符串

1. 字符串转数字

　　如将“32”转为32，将“3.1415”转为3.1415，将“567283”转为567283。使用：

//Convert string to integer, more @http://www.cplusplus.com/reference/clibrary/cstdlib/atoi/
int atoi ( const char * str );
//Convert string to double, more @http://www.cplusplus.com/reference/clibrary/cstdlib/atof/
double atof ( const char * str );
// Convert string to long integer,more @http://www.cplusplus.com/reference/clibrary/cstdlib/atol/
long int atol ( const char * str );  

//Read formatted data from string, more @http://www.cplusplus.com/reference/clibrary/cstdio/sscanf/
int sscanf ( const char * str, const char * format, ...);

　　Example1:


Example1

　　Example2:


Example2



2. [b]数字转字符串[/b]

　　如将32转为“32”，将3.1415转为“3.1415”，将567283转为“567283”。使用：

//Write formatted data to string, more @http://www.cplusplus.com/reference/clibrary/cstdio/sprintf/
int sprintf ( char * str, const char * format, ... );

//Convert integer to string (non-standard function), more @http://www.cplusplus.com/reference/clibrary/cstdlib/itoa/
//This function is not defined in ANSI-C and is not part of C++, but is supported by some compilers.
//A standard-compliant alternative for some cases may be sprintf.
char *  itoa ( int value, char * str, int base );

　　Example3:


Example3