TXmlEngString Class Reference

#include <xml/utils/xmlengxestrings.h>

Link against: xmlengineutils.lib

class TXmlEngString : public TXmlEngConstString

Inherits from

TXmlEngString
- TXmlEngConstString

Public Member Functions
	TXmlEngString()
	TXmlEngString(char *)
IMPORT_C HBufC *	AllocAndFreeL()
IMPORT_C HBufC *	AllocAndFreeLC()
IMPORT_C void	AppendL(TXmlEngString)
IMPORT_C void	AppendL(TXmlEngString, TXmlEngString)
void	Close()
IMPORT_C void	Free()
TXmlEngString	PushL()
void	Set(char *)
IMPORT_C void	Set(TXmlEngString &)
IMPORT_C void	SetL(const TDesC &)
IMPORT_C void	SetL(const TDesC8 &)

Protected Member Functions
	TXmlEngString(const TXmlEngConstString &)

Inherited Attributes
	TXmlEngConstString::iString

Inherited Functions
	TXmlEngConstString::AllocL()const
	TXmlEngConstString::AllocLC()const
	TXmlEngConstString::Compare(TXmlEngConstString)const
	TXmlEngConstString::CopyL()const
	TXmlEngConstString::Cstring()const
	TXmlEngConstString::CstringDef(const char *)const
	TXmlEngConstString::Equals(TXmlEngConstString)const
	TXmlEngConstString::IsNull()const
	TXmlEngConstString::Length()const
	TXmlEngConstString::NotNull()const
	TXmlEngConstString::PtrC8()const
	TXmlEngConstString::Size()const
	TXmlEngConstString::TXmlEngConstString()
	TXmlEngConstString::TXmlEngConstString(const char *)

Detailed Description

General-purpose string used in libxml2-based API's.

This class holds a zero-terminated sequence of bytes (c-style string). It is commonly used to represent a sequence of UTF-8 characters.

TXmlEngString objects should be treated as if they were pointers. The destructor for TXmlEngString does nothing. This means that the developer needs to free the memory allocated by TXmlEngString by calling Free() or Close() (Close() is an alias for Free()) and to do so only once.

The reason for this design is that the goal is to have a string class that is as small as a one-pointer sized object that is mostly stored on the stack, not on the heap (and therefore no additional memory allocation is required). It is also as flexible as possible to allow developers to create their own derived classes which may provide auto_ptr-like or reference counting solutions.

The contents of this class can be replaced, destroyed, copied and converted to c strings and Symbian descriptor types.

The contents of TXmlEngString may also be modified with AppendL().

When TXmlEngString is the return type in libxml2 based API's, this usually indicates that a string has been newly allocated, which should be freed by the method caller.

Constructor & Destructor Documentation

TXmlEngString ( )

TXmlEngString

(

)

[inline]

Default constructor

TXmlEngString ( char * )

TXmlEngString

(

char *

aString

)

[inline]

Constructs a new string from a given c string. Ownership is transferred and the string must be freed with Free() or Close().

Parameter	Description
aString	A heap-based c string

TXmlEngString ( const TXmlEngConstString & )

TXmlEngString

(

const TXmlEngConstString &

aStr

)

[protected, inline]

Constructs the object from a TXmlEngConstString

Parameter	Description
aStr	The string to initialize from

Member Function Documentation

AllocAndFreeL ( )

IMPORT_C HBufC *

AllocAndFreeL

(

)

Creates a new UTF-16 HBufC from the UTF-8 string contents and transfers ownership of the string. The string held by this object is freed.

Typical use:

      ...
      HBufC* attrValue = attr.WholeValueCopyL().AllocAndFreeL();
      ...

AllocAndFreeLC ( )

IMPORT_C HBufC *

AllocAndFreeLC

(

)

Creates a new UTF-16 HBufC from the UTF-8 string contents and transfers ownership of the string. The result is placed on the cleanup stack. The string held by this object is freed.

Typical use:

      ...
      HBufC* attrValue = attr.WholeValueCopyL().AllocAndFreeL();
      ...

AppendL ( TXmlEngString )

IMPORT_C void

AppendL

(

TXmlEngString

aStr

)

Appends new text to the string

leave: KErrNoMemory Memory allocation failure

Parameter	Description
aStr	The string to add

AppendL ( TXmlEngString, TXmlEngString )

IMPORT_C void	AppendL	(	TXmlEngString	aStr1,
			TXmlEngString	aStr2
		)

Appends new text to the string.

leave: KErrNoMemory Memory allocation failure

Parameter	Description
aStr1	The first string to append
aStr2	The second string to append

Close ( )

void

(

)

[inline]

Frees the string

Free ( )

IMPORT_C void

Free

(

)

Frees the string

PushL ( )

TXmlEngString

PushL

(

)

[inline]

Pushes this string to the cleanup stack. This must be matched with a corresponding call to CleanupStack::Pop() or CleanupStack::PopAndDestroy().

leave: KErrNoMemory Memory allocation failure

Returns: This object

Set ( char * )

void

Set

(

char *

aStr

)

[inline]

Reimplemented from TXmlEngConstString::Set(char *)

Sets a new value. The old string is freed. Ownership is transferred and the string must be freed with Free() or Close().

Parameter	Description
aStr	The new string

Set ( TXmlEngString & )

IMPORT_C void

Set

(

TXmlEngString &

aSrc

)

Transfers a string and its ownership from another TXmlEngString object. If this object currently stores a string it is freed.

Parameter	Description
aSrc	The source string

SetL ( const TDesC & )

IMPORT_C void

SetL

(

const TDesC &

aDes

)

Initializes the string, converting from a UTF-16 descriptor to a UTF-8 zero-terminated string.

leave

One of the system-wide error codes

Parameter	Description
aDes	The new value

SetL ( const TDesC8 & )

IMPORT_C void

SetL

(

const TDesC8 &

aDes

)

Initializes the string from a descriptor

leave

One of the system-wide error codes

Parameter	Description
aDes	The new value