几个字符串转换的例子

PART ONE :- DECIMAL CONVERSIONS

Decimal To Hexa :-
------------------

Use _itoa( ) function and set radix to 16.

char hexstring[ 10];
int number = 30;
itoa( number, hexstring, 16);

In hexstring is 1e.


Hexa To Decimal :-
------------------
a)
You can use strtol function and you can specify base.
char * hexstring= "ABCDEF";
char * p;
int number = strtol(hexstring, &p, 16);

b)
bool HexToDecimal ( char* HexNumber, int& Number)
{
char* pStopString;
Number = strtol (HexNumber, &pStopString, 16);
return ( bool)(Number != LONG_MAX);
}


Decimal to Time :-
------------------

char *DecToTime( float fTime, char *szTime)
{
int nHrs, nMin, nSec;
fTime *= 3600;
nHrs = ( int)fTime / 3600;
nMin = ( int)(fTime - nHrs * 3600) / 60;
nSec = ( int)(fTime - nHrs * 3600 - nMin * 60);
wsprintf(szTime, "%02d.%02d.%02d Hrs.Min.Sec.", nHrs, nMin, nSec);
return szTime;
}



PART TWO :- STRING CONVERSIONS


String to Hexa :-
-----------------

sscanf(string, %04X, &your_word16);
// where string = your string and 04 = length of your string and X = hex


Hex to CString
---------------

CString Str;
unsigned char Write_Buff[ 1 ];
Write_Buff[ 0] = 0x01;
Str.Format( "0x0%x",Write_Buff[ 0]);


COleVariant to CString
----------------------

CString strTemp;
COleVariant Var;
Var = "FirstName";
strTemp = Var.bstrVal;
AfxMessageBox(strTemp);


CString to Char Pointer
-----------------------
a)
CString MyString = "ABCDEF";
char * szMyString = ( char *) (LPCTSTR) MyString;

b)
char *pBuffer = new char[ 1024];
CString strBuf = "Test";
pBuffer = strBuf.GetBuffer( sizeof(pBuffer));


Char Pointer to CString
-----------------------

char * mystring = "12345";
CString string = mystring;


Double to CString including the fractional part :-
--------------------------------------------------

CString strValue,strInt, strDecimal;
int decimal,sign;
double dValue = 4.125;
strValue = _fcvt(dValue, 6 ,&decimal,&sign); // Now decimal contains 1 because there is only one digit before the .
strInt = strValue.Left(decimal); // strInt contains 4
strDecimal = strValue.Mid(decimal); // strDecimal contains 125

CString strFinalVal;
strFinalVal.Format( "%s.%s",strInt,strDecimal); // strFinalVal contains 4.125


Double To CString :-
--------------------
CString strValue;
int decimal,sign;

double dValue = 123456789101112;
strValue = _ecvt(dValue, 15,&decimal,&sign); // Converting double to string


CString To Double :-
---------------------

strValue = "121110987654321";
dValue = atof(strValue);


CString to LPCSTR :-
--------------------

CString str1 = _T( "My String");
int nLen = str1.GetLength();
LPCSTR lpszBuf = str1.GetBuffer(nLen);
// here do something with lpszBuf...........
str1.ReleaseBuffer();


CString to LPSTR :-
--------------------

CString str = _T( "My String");
int nLen = str.GetLength();
LPTSTR lpszBuf = str.GetBuffer(nLen);
// here do something with lpszBuf...........
str.ReleaseBuffer();


CString to WCHAR*
-----------------

CString str = "A string here" ;
LPWSTR lpszW = new WCHAR[ 255];

LPTSTR lpStr = str.GetBuffer( str.GetLength() );
int nLen = MultiByteToWideChar(CP_ACP, 0,lpStr, - 1, NULL, NULL);
MultiByteToWideChar(CP_ACP, 0, lpStr, - 1, lpszW, nLen);
AFunctionUsesWCHAR( lpszW );
delete [] lpszW;


LPTSTR to LPWSTR
----------------
int nLen = MultiByteToWideChar(CP_ACP, 0, lptStr, - 1, NULL, NULL);
MultiByteToWideChar(CP_ACP, 0, lptStr, - 1, lpwStr, nLen);


string to BSTR
--------------
string ss = "Girish";
BSTR _bstr_home = A2BSTR(ss.c_str());


CString to BSTR
---------------
CString str = "whatever" ;
BSTR resultsString = str.AllocSysString();


_bstr_t to CString
-------------------

#include
#include
_bstr_t bsText( "Hai Bayram");
CString strName;
W2A(bsText, strName.GetBuffer( 256), 256 );
strName.ReleaseBuffer();
AfxMessageBox(strName);

char szFileName[ 256];
GetModuleFileName(NULL,szFileName, 256);
AfxMessageBox(szFileName);


PART THREE :- CHARACTER ARRAYS

Char array to integer
---------------------

char MyArray[ 20];
int nValue;

nValue = atoi(MyArray);


Char array to float
-------------------

char MyArray[ 20];
float fValue;

fValue = atof(MyArray);


Char Pointer to double
----------------------

char *str = " -343.23 ";
double dVal;
dVal = atof( str );


Char Pointer to integer
-----------------------

char *str = " -343.23 ";
int iVal;
iVal = atoi( str );


Char Pointer to long
--------------------

char *str = "99999";
long lVal;
lVal = atol( str );


Char* to BSTR
-------------
char * p = "whatever";
_bstr_t bstr = p;


Float to WORD and Vice Versa
-----------------------------
float fVar;
WORD wVar;
fVar = 247.346;
wVar = (WORD)fVar; //Converting from float to WORD. The value in wVar would be 247
wVar = 247;
fVar = ( float)fVar; //Converting from WORD to float. The value in fVar would be 247.00

All luck and have a great time.