函数原型：

char *_itoa( int , char *, int  );  //ANSIwchar_t * _itow( int , wchar_t *, int  );//UNICODE _itot 只是一个宏，根据系统定义的字符集来去_itoa或者_itow， 对应的安全函数为_itot_s 说明:把int 转化为字符串,value为被转化的值,string为转化的目的字符串, radix为基数必须在2到36之间. 所需头文件 #include 
    
      举例说明:这里用它们的安全函数: _itoa_s    _itow_s char szYearA[5] = {0}; WCHAR szYearW[5] = {0}; _itoa_s(100, szYearA, 10); _itow_s(100, szYearW, 10); atoi     atof     atol
    

Convert strings to double (atof), integer (atoi, _atoi64), or long (atol).

double atof( const char * );int atoi( const char * );_int64 _atoi64( const char * );long atol( const char * ); 举例： 	double d1 = atof("sa34");  //d1 = 0.00000000000000000 	double d2 = atof("34gdf"); //d2 = 34.000000000000000 	double d3 = atof("-0343"); //d3 = -343.00000000000000 	double d4 = atof("008");   //d4 = 8.0000000000000000 	int i1 = atoi("df");       //i1 = 0 	int i2 = atoi("54.34");    //i2 = 54 	int i3 = atoi("-54");      //i3 = -54 	int i4 = atoi("09");       //i4 = 9