C++ TDes16类代码示例

/** Reads a descriptor setting.
@param aKey Key of setting to be read.
@param aValue Returns the value of the setting if it is a descriptor.
@return
	KErrNone if successful,
	KErrNotFound if the setting does not exist,
	KErrArgument if the setting exists but is not a descriptor,
	KErrOverflow if the descriptor is too small to receive the value in the repository,
	plus other system-wide error codes.
@post Transactions fail only on those "other system-wide error codes".
@capability Dependent Caller must satisfy the read access policy of that key in the repository.
*/
EXPORT_C TInt CRepository::Get(TUint32 aKey, TDes16& aValue)
	{
	TPtr8 ptr8((TUint8*)aValue.Ptr(), 0, aValue.MaxSize());
	TInt ret=Get(aKey,ptr8);
	if (ret==KErrNone)
		aValue.SetLength(ptr8.Length()/2);
	return ret;
	}

// -----------------------------------------------------------------------------
// JPLangUtil::ConvertFullHiragnaToFullKatakana
// Converts Full-width Hiragana and Special Character text found in
// aUnicodeSource to their Full-width counterparts and places the
// resulting text into aUnicodeTarget.
// -----------------------------------------------------------------------------
//
EXPORT_C TInt JPLangUtil::ConvertFullHiragnaToFullKatakana
                       ( const TDesC16& aUnicodeSource, TDes16& aUnicodeTarget )
    {
    TInt totalConverted( 0 );
    const TInt length( aUnicodeSource.Length() );
    const TInt maxLength( aUnicodeTarget.MaxLength() );
    if( length > maxLength )
        {
        return KErrTooBig;
        }

    const TUint comp = KFullWidthKatakanaSmallA - KFullWidthHiraganaSmallA;

    aUnicodeTarget.Zero();
    for( TInt i( 0 ); i < length; ++i )
        {
        const TText uniChar( aUnicodeSource[i] );
        TText uniChar2(0);
        if (i + 1 < length)
            {
            uniChar2 = aUnicodeSource[i+1];
            }
        // First check if this is this Full Width Katakana
        if (KFullWidthHiraganaSmallA <= uniChar && uniChar <= KFullWidthHiraganaVU)
            {
            if (uniChar == KFullWidthHiraganaU
             && uniChar2 == KFullWidthHiraganaVoicedSound)
                {
                aUnicodeTarget.Append(KFullWidthKatakanaSmallVU);
                totalConverted++;
                i++;
                }
            else
                {
                TUint katakana = uniChar + comp;
                if (IsKatakana(katakana))
                    {
                    aUnicodeTarget.Append(katakana);
                    totalConverted++;
                    }
                }
            }
        else
            {
            aUnicodeTarget.Append(uniChar);
            totalConverted++;
            }
        }

    // Now handle special characters
    // This logic may be moved into this function to avoid another loop over
    // the text
    totalConverted +=
        UnicodeTextUtil::ConvertSpecialCharactersInPlace( EFullToHalfWidth,
                                                          aUnicodeTarget );

    return totalConverted;
    }

void CBatmonContainer::Value(TUint8 aUnit,TUint16 aAddress,TDes16& aValue) const
{
  TRAPD(err,HWNetmon::ValueL(aUnit,aAddress,aValue,HWNetmon::EExt|HWNetmon::ESigned));
  if(err!=KErrNone)
  {
    aValue.Zero();
    aValue.Append('?');
  }
}

TInt TEnvVar::Externalize(TDes16& aBuffer)
	{
	if (iName==0) 
		return 0;
	aBuffer.Append(*iName);
	aBuffer.Append(TChar(0));
	aBuffer.Append(*iValue);
	aBuffer.Append(TChar(0));
	return 1;
	}

EXPORT_C TInt CLANLinkCommon::ReadDes(const TDesC& aField, TDes16& aValue)
{
	// Emulate reading of following parameters only:
	// LAN_BEARER\LAN_BEARER_LDD_FILENAME
	// LAN_BEARER\LAN_BEARER_LDD_NAME
	// LAN_BEARER\LAN_BEARER_PDD_FILENAME
	// LAN_BEARER\LAN_BEARER_PDD_NAME

	_LIT(KLanBearer, "LANBearer\\");
	const TInt KLanBearerTokenSize = 10;

	TPtrC field(aField.Left(KLanBearerTokenSize));	// "LANBearer"

	if (field.Compare(KLanBearer()) == 0)
		{
		_LIT(KLanBearerLddFilename, "LDDFilename");
		_LIT(KLanBearerLddName, "LDDName");
		_LIT(KLanBearerPddFilename, "PDDFilename");
		_LIT(KLanBearerPddName, "PDDName");

		field.Set(aField.Mid(KLanBearerTokenSize));	// skip "LANBearer\\"
		if (field.CompareF(KLanBearerLddFilename) == 0)
			{
			aValue.Copy(LinkProvision().LddFilename());
			}
		else
		if (field.CompareF(KLanBearerLddName) == 0)
			{
			aValue.Copy(LinkProvision().LddName());
			}
		else
		if (field.CompareF(KLanBearerPddFilename) == 0)
			{
			aValue.Copy(LinkProvision().PddFilename());
			}
		else
		if (field.CompareF(KLanBearerPddName) == 0)
			{
			aValue.Copy(LinkProvision().PddName());
			}
		else
			{
			return KErrNotSupported;
			}
		return KErrNone;
		}
	else
		{
		return KErrNotSupported;
		}
}

TInt CDummyNifAgentRef::DoReadDes(const TDesC& aField, TDes16& aValue,const RMessagePtr2* /*aMessage*/)
{
	TInt result = KErrNotFound;
	if (ipIniFileReader !=0)
	{
		TPtrC value;
		if (ipIniFileReader->FindVar(iData.KCommDbSectionName,aField,value))
		{
			aValue.Copy(value);
			result=KErrNone;
		}
	}
	//use hardcoded only if the ini file read or search failed
	if (KErrNotFound==result)
	{
		result=KErrNone;
		//
		if (TPtrC(KCDTypeNameRecordName)==aField)
			aValue=iData.KPppCommdbName;
		else if (iData.KModemPortString==aField)
			aValue=iData.KPppPortString;
		else if (iData.KModemCsyString==aField)
			aValue=iData.KPppCsyString;
		else
			result=KErrNotFound;
	}
	//
	LOG_ERR_PRINTF4(_L("--------------- Config param used: %S = %S (err %d)"),&aField,&aValue,result);
	//
	return result;
}

// -----------------------------------------------------------------------------
// UnicodeTextUtil::ConvertASCIIInPlace
// Converts all ASCII *in-place* from either Half to Full-width or vice versa,
// depending on the direction specified by aDirection.
// Returns: The total number of characters converted.
// -----------------------------------------------------------------------------
//
TInt UnicodeTextUtil::ConvertASCIIInPlace( TConvDirection aDirection,
                                           TDes16& aUnicodeText )
    {
    TInt totalConverted( 0 );
    TText lowerBound( ( aDirection == EHalfToFullWidth ) ?
                        KHalfWidthASCIILowerBound :
                        KFullWidthASCIILowerBound );
    TText upperBound( ( aDirection == EHalfToFullWidth ) ?
                        KHalfWidthASCIIUpperBound :
                        KFullWidthASCIIUpperBound );
    TInt offset( ( aDirection == EHalfToFullWidth ) ?
                   KHalfToFullWidthASCIIOffset :
                   -KHalfToFullWidthASCIIOffset );
    for( TInt i( 0 ); i < aUnicodeText.Length(); ++i )
        {
        const TText uniChar( aUnicodeText[i] );
        if( uniChar >= lowerBound && uniChar <= upperBound )
            {
            TText convertedChar( static_cast<TText>( uniChar + offset ) );
            aUnicodeText[i] = convertedChar;
            totalConverted++;
            }
        }
    return totalConverted;
    }

/**
Reads data from the stream buffer into the specified descriptor.
On return, contains the data read from the stream buffer

@param aDes The target descriptor for the data read from the stream buffer
@param aLength The maximum number of bytes to be read
@return KErrNone If all bytes read successfully.
@return	KErrCorrupt If reading fails.
@return KErrEof If end of file is reached.
@return ... Any one of the system-wide error codes for other errors.
*/
EXPORT_C TInt RZipFileMemberReaderStream::Read(TDes16& aDes, TInt aLength)
{
	TUint32 numBytesRead = 0;
	TInt err = Read(CONST_CAST(TByte*,(const TByte*)aDes.Ptr()), 2*aLength, &numBytesRead);
	if (err != KErrNone)
	{
		aDes.SetLength( (err==KErrEof) ? numBytesRead>>2 : 0 );
		return err;
	}

void CMemSpyMemStreamReader::ReadL( TDes16& aDes )
    {
    // The kernel driver only ever writes narrow descriptors.
    // However, we can expand them to be UCS2
    const TInt length = ReadInt32L();

    // Need to check the remaining text is actually present...
    IsAvailableL( length );

    // Set final length in descriptor
    aDes.SetLength( length );

    // Read each char
    TUint16* dest = const_cast< TUint16* >( aDes.Ptr() );
    for( TInt i=0; i<length; i++ )
        {
        *dest++ = *iCurrent++;
        }
    }

 /**
   * Converts a descriptor of type TBuf16 to character stream
   *
   * @param aSrc is the descriptor to be converted , aDes is the 
   * reference to the character sream where the result of conversion 
   * is stored , n_size specifies the conversion size of the string 
   * @return Status code (0 is ESuccess, -1 is EInsufficientMemory, 
   * -2 is EInvalidSize , -4 is EInvalidPointer, -8 is EInvalidWCSSequence)
   */
EXPORT_C int Tbuf16ToChar(TDes16& aSrc, char* aDes, int& n_size)
{	
    unsigned int ilen = aSrc.Length();
    int retval = ESuccess;
    wchar_t *temp16String = NULL;
    int minusone = -1;
    
    if (0 == ilen)
    {
    	return EDescriptorNoData;
    }
    else if(!aDes)
    {
    	return EInvalidPointer;
    }
    
    else if(n_size < ilen*2+1)
    {
    	n_size = ilen*2;
    	return EInvalidSize;
    }
        		
	temp16String = new wchar_t [ilen+1];
	if (!temp16String)
	{
		return EInsufficientSystemMemory;
	}
	
	wmemcpy(temp16String, (const wchar_t *)aSrc.Ptr(), ilen);
	temp16String[ilen] = L'\0'; 	
	
	if(minusone != wcstombs(aDes, (const wchar_t*)temp16String, ilen*2))
	{
	    aDes[ilen*2] = '\0'; 
	}
	else 
	{
		retval = EInvalidWCSSequence;
	}
	
	delete []temp16String;	
	return retval;
}

EXPORT_C int WcharToTbuf16(const wchar_t* aSrc, TDes16& aDes)
{
    unsigned int ilen = 0;
	if ( !aSrc )
	{
		return EInvalidPointer;
	}
	else
	{
		ilen = wcslen(aSrc);
		if(ilen > aDes.MaxLength())
		{
			return EInsufficientMemory; 
		}	
	}
	
	aDes.Copy((const TUint16*)aSrc, ilen);
	return ESuccess;
}

void CT_KOI8R::Merge_Big(TDesC8& aSource, TDes16& aTarget)
	{
	TInt length = aSource.Length();
	TInt i = 0;
	for(i=0;i<length-1;i++)
		{
		TInt64 temp = *(aSource.Ptr()+(i))*16*16 + *(aSource.Ptr()+i+1);
		aTarget.Append(temp);
		i++;
		}	
	}

/** Generates a file name of the form FFFFF*<aPos>.TXT (aLong.3)

	@param aBuffer The filename will be returned here
	@param aLong   Defines the longitude of the file name 
	@param aPos	   Defines the number that will be attached to the filename
*/
void FileNameGen(TDes16& aBuffer, TInt aLong, TInt aPos) 
{
	TInt padding;
	TInt i=0;
	TBuf16<10> tempbuf;
	
	_LIT(KNumber,"%d");
	tempbuf.Format(KNumber,aPos);
	padding=aLong-tempbuf.Size()/2;
	aBuffer=_L("");
	while(i<padding)
	{
		aBuffer.Append('F');
		i++;
	}
	aBuffer.Append(tempbuf);
	
	_LIT(KExtension1, ".TXT");
	aBuffer.Append(KExtension1);
}

//translate from unicode big endian TDesC8 to TDes16
void CT_TURKISHLOCKING::Unicode_Big(TDesC8& aSource, TDes16& aTarget)
	{
	TInt length = aSource.Length();
	TInt i = 0;
	for(i=0;i<length-1;i++)
		{
		TInt32 temp = *(aSource.Ptr()+(i))*16*16 + *(aSource.Ptr()+i+1);
		aTarget.Append(temp);
		i++;
		}	
	}

EXPORT_C int WstringToTbuf16(wstring& aSrc, TDes16& aDes)
{
    int retval = ESuccess;
    const wchar_t* wcharString = aSrc.c_str();
    
    if (L'\0' == wcharString[0])
    {
    	return EStringNoData;
    }
    
    int len= wcslen(wcharString);
    if ((wcslen(wcharString)) > aDes.MaxLength())
    if (len > aDes.MaxLength())
    {
    	return EInsufficientMemory;
    }
    
	aDes.Copy((const TUint16*)wcharString);
	
    return retval;	
}