WStr Class Reference

#include <strclass.h>

Inheritance diagram for WStr:

Public Member Functions
	WStr ()
	WStr (const wchar_t *wcstr)
	WStr (const WStr &ws)
	WStr (const MaxSDK::Util::MaxString &ws)
	WStr (const MaxSDK::Util::MaxStringCast< WCHAR > &ws)
	WStr (const QString &qstring)
	Conversion constructor, from QString. More...
	~WStr ()
wchar_t *	dataForWrite (size_t nchars=(size_t) -1)
	Returns a pointer to this string which can be written to with up to 'nchars' characters. More...
const wchar_t *	data () const
	operator const wchar_t * () const
	operator QString () const
	Conversion operator to QString. More...
void	Resize (int nchars)
int	Length () const
int	length () const
int	ByteCount () const
int	LanguageCharacterCount () const
size_t	AllocatedChars () const
bool	isNull () const
WStr &	operator= (const WStr &ws)
WStr &	operator= (const MaxSDK::Util::MaxString &mstr)
WStr &	operator= (const wchar_t *wcstr)
WStr &	operator= (const MaxSDK::Util::MaxStringCast< WCHAR > &mstr)
WStr	operator+ (const WStr &ws) const
WStr &	operator+= (const WStr &ws)
WStr &	Append (const WStr &ws)
WStr &	append (const WStr &ws)
WStr &	remove (int pos)
WStr &	remove (int pos, int N)
WStr	Substr (int start, int nchars) const
wchar_t	operator[] (int i) const
	Returns the nth character of this string. More...
int	first (wchar_t c) const
int	last (wchar_t c) const
bool	operator== (const WStr &ws) const
bool	operator== (wchar_t c) const
bool	operator!= (const WStr &ws) const
bool	operator!= (wchar_t c) const
bool	operator< (const WStr &ws) const
bool	operator<= (const WStr &ws) const
bool	operator> (const WStr &ws) const
bool	operator>= (const WStr &ws) const
void	toUpper ()
void	toLower ()
int	printf (const wchar_t *format,...)
	Write a formatted string into this WStr. More...
int	printf_l (const wchar_t *format, const _locale_t theLocale,...)
	Write a formatted string into this WStr using specified locale. More...
int	vprintf (const wchar_t *format, va_list args)
	Write a formatted string into this WStr. More...
int	vprintf_l (const wchar_t *format, const _locale_t theLocale, va_list args)
	Write a formatted string into this WStr specified locale. More...
WStr	MultiByteCharacterSubString (int firstCharacterIndex, int numberOfMBCharacters) const
wchar_t *	ToBSTR () const
MaxSDK::Util::MaxStringCastCP	ToCP (UINT cp, size_t *length=NULL) const
MaxSDK::Util::MaxStringCast< char >	ToACP (size_t *length=NULL) const
MaxSDK::Util::MaxStringCastUTF8	ToUTF8 (size_t *length=NULL) const
MaxSDK::Util::MaxStringCast< WCHAR >	ToOLESTR (size_t *length=NULL) const
MaxSDK::Util::MaxStringCast< WCHAR >	ToUTF16 (size_t *length=NULL) const
MaxSDK::Util::MaxStringCast< unsigned int >	ToUTF32 (size_t *length=NULL) const
MaxSDK::Util::MaxString	ToMaxString () const
void	ToMaxString (MaxSDK::Util::MaxString &) const
CStr	ToCStr () const
WStr	ToWStr () const
const wchar_t *	ToMCHAR (size_t *length=NULL) const
WStr	ToMSTR () const
bool	EndsWith (const WStr &s, bool caseSensitive=true)
	Returns true if the string ends with s; otherwise returns false. More...
bool	EndsWith (wchar_t c, bool caseSensitive=true)
	Returns true if the string ends with c; otherwise returns false. More...
bool	StartsWith (const WStr &s, bool caseSensitive=true)
	Returns true if the string starts with s; otherwise returns false. More...
bool	StartsWith (wchar_t c, bool caseSensitive=true)
	Returns true if the string starts with c; otherwise returns false. More...
size_t	NumberOfLines () const
	Returns the number of line feeds inside a string. More...
size_t	Replace (const wchar_t *pFind, const wchar_t *pReplaceBy, bool firstOnly=false, size_t startPosition=0)
	Replaces one substring with another in this string. More...

Static Public Member Functions
static WStr	FromBSTR (const wchar_t *string, size_t length=(size_t) -1)
static WStr	FromCP (UINT cp, const char *string, size_t length=(size_t) -1)
static WStr	FromACP (const char *string, size_t length=(size_t) -1)
static WStr	FromUTF8 (const char *string, size_t length=(size_t) -1)
static WStr	FromOLESTR (const wchar_t *string, size_t length=(size_t) -1)
static WStr	FromUTF16 (const wchar_t *string, size_t length=(size_t) -1)
static WStr	FromUTF32 (const unsigned int *string, size_t length=(size_t) -1)
static WStr	FromMaxString (MaxSDK::Util::MaxString &string)
static WStr	FromCStr (const CStr &string)
static WStr	FromWStr (const WStr &string)
static WStr	FromMCHAR (const wchar_t *string, size_t length=(size_t) -1)
static WStr	FromMSTR (const WStr &string)
Static Public Member Functions inherited from MaxHeapOperators
static UtilExport void *	operator new (size_t size)
	Standard new operator used to allocate objects If there is insufficient memory, an exception will be thrown. More...
static UtilExport void *	operator new (size_t size, const std::nothrow_t &e)
	Standard new operator used to allocate objects if there is insufficient memory, NULL will be returned. More...
static UtilExport void *	operator new (size_t size, const char *filename, int line)
	New operator used to allocate objects that takes the filename and line number where the new was called If there is insufficient memory, an exception will be thrown. More...
static UtilExport void *	operator new (size_t size, int block_type, const char *filename, int line)
	New operator used to allocate objects that takes the type of memory, filename and line number where the new was called If there is insufficient memory, an exception will be thrown. More...
static UtilExport void *	operator new (size_t size, const std::nothrow_t &e, const char *filename, int line)
	New operator used to allocate objects that takes the filename and line number where the new was called If there is insufficient memory, NULL will be returned. More...
static UtilExport void *	operator new (size_t size, unsigned long flags)
	New operator used to allocate objects that takes extra flags to specify special operations If there is insufficient memory, an exception will be thrown. More...
static UtilExport void *	operator new (size_t size, const std::nothrow_t &e, unsigned long flags)
	New operator used to allocate objects that takes extra flags to specify special operations If there is insufficient memory, NULL will be returned. More...
static UtilExport void *	operator new[] (size_t size)
	New operator used to allocate arrays of objects If there is insufficient memory, an exception will be thrown. More...
static UtilExport void *	operator new[] (size_t size, const std::nothrow_t &e)
	New operator used to allocate arrays of objects If there is insufficient memory, NULL will be returned. More...
static UtilExport void *	operator new[] (size_t size, const char *filename, int line)
	New operator used to allocate arrays of objects If there is insufficient memory, an exception will be thrown. More...
static UtilExport void *	operator new[] (size_t size, int block_type, const char *filename, int line)
	New operator used to allocate arrays of objects. More...
static UtilExport void *	operator new[] (size_t size, const std::nothrow_t &e, const char *filename, int line)
	New operator used to allocate arrays of objects If there is insufficient memory, NULL will be returned. More...
static UtilExport void *	operator new[] (size_t size, unsigned long flags)
	New operator used to allocate arrays of objects If there is insufficient memory, an exception will be thrown. More...
static UtilExport void *	operator new[] (size_t size, const std::nothrow_t &e, unsigned long flags)
	New operator used to allocate arrays of objects If there is insufficient memory, NULL will be returned. More...
static UtilExport void	operator delete (void *ptr)
	Standard delete operator used to deallocate an object If the pointer is invalid, an exception will be thrown. More...
static UtilExport void	operator delete (void *ptr, const std::nothrow_t &e)
	Standard delete operator used to deallocate an object If the pointer is invalid, nothing will happen. More...
static UtilExport void	operator delete (void *ptr, const char *filename, int line)
	Delete operator used to deallocate an object that takes the filename and line number where the delete was called If the pointer is invalid, an exception will be thrown. More...
static UtilExport void	operator delete (void *ptr, int block_type, const char *filename, int line)
	Delete operator used to deallocate an object that takes the type of memory, filename and line number where the delete was called If the pointer is invalid, an exception will be thrown. More...
static UtilExport void	operator delete (void *ptr, const std::nothrow_t &e, const char *filename, int line)
	Delete operator used to deallocate an object that takes the filename and line number where the delete was called If the pointer is invalid, nothing will happen. More...
static UtilExport void	operator delete (void *ptr, unsigned long flags)
	Delete operator used to deallocate an object that takes extra flags to specify special operations If the pointer is invalid, an exception will be thrown. More...
static UtilExport void	operator delete (void *ptr, const std::nothrow_t &e, unsigned long flags)
	Delete operator used to deallocate an object that takes extra flags to specify special operations If the pointer is invalid, nothing will happen. More...
static UtilExport void	operator delete[] (void *ptr)
	Standard delete operator used to deallocate an array of objects If the pointer is invalid, an exception will be thrown. More...
static UtilExport void	operator delete[] (void *ptr, const std::nothrow_t &e)
	Standard delete operator used to deallocate an array of objects If the pointer is invalid, nothing will happen. More...
static UtilExport void	operator delete[] (void *ptr, const char *filename, int line)
	Delete operator used to deallocate an array of objects that takes the filename and line number where the delete was called If the pointer is invalid, an exception will be thrown. More...
static UtilExport void	operator delete[] (void *ptr, int block_type, const char *filename, int line)
	Delete operator used to deallocate an array of objects that takes the type of memory, filename and line number where the delete was called If the pointer is invalid, an exception will be thrown. More...
static UtilExport void	operator delete[] (void *ptr, const std::nothrow_t &e, const char *filename, int line)
	Delete operator used to deallocate an array of objects that takes the filename and line number where the delete was called If the pointer is invalid, nothing will happen. More...
static UtilExport void	operator delete[] (void *ptr, unsigned long flags)
	Delete operator used to deallocate an array of objects that takes extra flags to specify special operations If the pointer is invalid, an exception will be thrown. More...
static UtilExport void	operator delete[] (void *ptr, const std::nothrow_t &e, unsigned long flags)
	Delete operator used to deallocate an array of objects that takes extra flags to specify special operations If the pointer is invalid, an exception will be thrown. More...
static UtilExport void *	operator new (size_t size, void *placement_ptr)
	Placement new operator. More...
static UtilExport void	operator delete (void *ptr, void *placement_ptr)
	Placement delete operator. More...
static UtilExport void *	aligned_malloc (size_t size, size_t alignment)
	Allocates memory on a specified alignment boundary. More...
static UtilExport void *	aligned_realloc (void *ptr, size_t size, size_t alignment)
	Reallocates memory on a specified alignment boundary. More...
static UtilExport void	aligned_free (void *ptr)
	Frees a block of memory that was allocated with aligned_malloc/aligned_realloc. More...

Detailed Description

See also

Class CStr, UTF8Str and MaxString, Guidelines for Handling Character Strings.

Description:

A wide character string class. This class uses 16 bits to hold each character. Methods and operators are provided for calculating lengths, concatenation, substring operations, character searching, case conversion, comparison, and formatted writing. All methods are implemented by the system.

OLE file IO requires the wide characters of WStr.

Note

The memory occupied by a WStr object is cannot be larger than 2Gb.

Constructor & Destructor Documentation

WStr() [1/6]

WStr

(

)

Remarks

Constructor. The string is set to NULL.

WStr() [2/6]

WStr

(

const wchar_t *

wcstr

)

Remarks

Constructor. The string is initialized to the string passed.

WStr() [3/6]

WStr

(

const WStr &

ws

)

Remarks

Constructor. The string is initialized to the string passed.

WStr() [4/6]

WStr

(

const MaxSDK::Util::MaxString &

ws

)

Remarks

Constructor. The string is initialized to the string passed.

WStr() [5/6]

WStr

(

const MaxSDK::Util::MaxStringCast< WCHAR > &

ws

)

Remarks

Constructor. The string is initialized to the string passed.

WStr() [6/6]

WStr

(

const QString &

qstring

)

Conversion constructor, from QString.

~WStr()

~WStr

(

)

Remarks

Destructor. The string is deleted.

Member Function Documentation

dataForWrite()

wchar_t* dataForWrite

(

size_t

nchars = (size_t) -1

)

Returns a pointer to this string which can be written to with up to 'nchars' characters.

Remarks

The terminating null character is not included in nchars, so technically up to nchars+1 characters may be written.

Parameters

nchars

The minimum number of characters to allocate in the string buffer (excluding the terminating null character). A value of -1 specifies that the existing buffer should be re-used.

data()

const wchar_t* data

(

)

const

Remarks

Returns a const pointer to the string. If the string is NULL, a pointer to 0 is returned.

operator const wchar_t *()

operator const wchar_t *

(

)

const

Remarks

Returns a const pointer to the string. If the string is NULL, a pointer to 0 is returned.

operator QString()

operator QString

(

)

const

Conversion operator to QString.

Resize()

void Resize

(

int

nchars

)

Remarks

Reallocates the string to contain nchars characters. If the string is enlarged it is padded with blanks.

Parameters:

int nchars

Specifies the new number of characters for the string.

Length()

int Length

(

)

const

Remarks

Returns the number of WCHAR that are used to represents this string, including spaces, but excluding the terminal NULL character.

length()

int length ( ) const

inline

Remarks

Returns the number of WCHAR that are used to represents this string, including spaces, but excluding the terminal NULL character.

{ return Length(); }

ByteCount()

int ByteCount

(

)

const

Remarks

Returns the number of bytes used to store the string in memory, including spaces, but excluding the terminating NULL character.

LanguageCharacterCount()

int LanguageCharacterCount

(

)

const

Remarks

Returns the number of natural language characters the string is represented on, including spaces, but excluding the terminal NULL character.

This may be equal or less than the amount of WCHAR used to store the string in memory. For example, a chinese character might take two WCHARs. Length() will count the character as two distinct WCHARs. LanguageCharacterCount() will count it as a single character.

AllocatedChars()

size_t AllocatedChars

(

)

const

Remarks

Returns the total number of WCHAR allocated to store the string. Including the NULL character and any unused WCHAR.

isNull()

bool isNull ( ) const

inline

Remarks

Returns TRUE if the string length is 0; otherwise FALSE.

{ return data()[0]==0; }

operator=() [1/4]

WStr& operator=

(

const WStr &

ws

)

Remarks

Assignment operator. In release 3.0 and later this operator checks for self-assignment.

operator=() [2/4]

WStr& operator=

(

const MaxSDK::Util::MaxString &

mstr

)

Remarks

Assignment operator.

operator=() [3/4]

WStr& operator=

(

const wchar_t *

wcstr

)

Remarks

Assignment operator.

operator=() [4/4]

WStr& operator=

(

const MaxSDK::Util::MaxStringCast< WCHAR > &

mstr

)

Remarks

Assignment operator.

operator+()

WStr operator+

(

const WStr &

ws

)

const

Remarks

Concatenation operator. Returns a new string that is this string with string ws appended.

operator+=()

WStr& operator+=

(

const WStr &

ws

)

Remarks

Concatenation. Returns this string with ws appended.

Append()

WStr& Append ( const WStr &  ws )

inline

Remarks

Concatenation. Returns this string with ws appended.

{ return ((*this) += ws); }

append()

WStr& append ( const WStr &  ws )

inline

Remarks

Concatenation. Returns this string with ws appended.

{ return ((*this) += ws); }

remove() [1/2]

WStr& remove

(

int

pos

)

Remarks

Returns this string with N characters removed from pos to the end.

Parameters:

int pos

Specifies the position to begin removing characters.

int N

Specifies the number of characters to remove.

remove() [2/2]

WStr& remove	(	int	pos,
		int	N
	)

Substr()

WStr Substr	(	int	start,
		int	nchars
	)		const

Remarks

Returns a substring of this string, beginning at position start, of length nchars.

operator[]()

wchar_t operator[]

(

int

i

)

const

Returns the nth character of this string.

Warning: In some environment, this function may return a partial character, especially for Asiatic languages. If you intend to do any advance transformation or interpretation of the returned data, you should consider calling WStr::MultiByteCharacterSubString instead.

Parameters

i	Index of that character.

first()

int first

(

wchar_t

c

)

const

Remarks

Returns the index of the first occurrence of character c in this string. Returns -1 if not found.

last()

int last

(

wchar_t

c

)

const

Remarks

Returns the index of the last occurrence of character c in this string. Returns -1 if not found.

operator==() [1/2]

bool operator==

(

const WStr &

ws

)

const

Remarks

Equality operator.

Returns

true if the strings are equal; otherwise false.

operator==() [2/2]

bool operator==

(

wchar_t

c

)

const

Remarks

Returns true if this string contain only the character c.

operator!=() [1/2]

bool operator!=

(

const WStr &

ws

)

const

Remarks

Inequality operator.

Returns

False if the strings are equal; otherwise true.

operator!=() [2/2]

bool operator!=

(

wchar_t

c

)

const

Remarks

Returns true if this string does not contain only the character c.

operator<()

bool operator<

(

const WStr &

ws

)

const

Remarks

Returns true if this string is less than ws; otherwise false.

operator<=()

bool operator<=

(

const WStr &

ws

)

const

Remarks

Returns true if this string is less than or equal to ws; otherwise false.

operator>()

bool operator>

(

const WStr &

ws

)

const

Remarks

Returns true if this string is greater than ws; otherwise false.

operator>=()

bool operator>=

(

const WStr &

ws

)

const

Remarks

Returns true if this string is greater than or equal to ws; otherwise false.

toUpper()

void toUpper

(

)

Remarks

Converts all character of this string to uppercase.

toLower()

void toLower

(

)

Remarks

Converts all character of this string to lowercase.

printf()

int printf	(	const wchar_t *	format,
			...
	)

Write a formatted string into this WStr.

Writes the format string, filled in by the optional arguments into this WStr. See the ISO C++ documentation for more information on printf and format strings.

Parameters

format	Specifies how to format the destination string.
...	optional arguments to format into the destination string.

Precondition

format is not null.

There are the correct number of elliptical arguments to fill the format string.

Postcondition

This string is replaced with the formatted string.

Returns

The number of characters written to this string, not including the null terminating character, or a negative value if an error occurs.

printf_l()

int printf_l	(	const wchar_t *	format,
		const _locale_t	theLocale,
			...
	)

Write a formatted string into this WStr using specified locale.

Writes the format string, filled in by the optional arguments into this WStr. See the ISO C++ documentation for more information on printf_l and format strings.

Parameters

format	Specifies how to format the destination string.
theLocale	The locale to use.
...	optional arguments to format into the destination string.

Precondition

format is not null.

There are the correct number of elliptical arguments to fill the format string.

Postcondition

This string is replaced with the formatted string.

Returns

The number of characters written to this string, not including the null terminating character, or a negative value if an error occurs.

vprintf()

int vprintf	(	const wchar_t *	format,
		va_list	args
	)

Write a formatted string into this WStr.

This method is similar to WStr::printf. Instead of taking a variable list of arguments as parameter, it takes a structure representing a variable list of arguments. This allows WStr objects to be used to build strings based on a format string and a variable number of arguments:

void LogMessage(const wchar_t* format, ...) {
va_list args;
va_start(args, format);
WStr buf;
buf.vprintf(format, args);
va_end(args);
// log the message contained by buf
}

vprintf_l()

int vprintf_l	(	const wchar_t *	format,
		const _locale_t	theLocale,
		va_list	args
	)

Write a formatted string into this WStr specified locale.

This method is similar to WStr::printf_l. Instead of taking a variable list of arguments as parameter, it takes a structure representing a variable list of arguments. This allows WStr objects to be used to build strings based on a format string, a locale, and a variable number of arguments:

void LogMessage_l(const wchar_t* format, const _locale_t theLocale, ...) {
va_list args;
va_start(args, format);
WStr buf;
buf.vprintf(format, theLocale, args);
va_end(args);
// log the message contained by buf
}

MultiByteCharacterSubString()

WStr MultiByteCharacterSubString	(	int	firstCharacterIndex,
		int	numberOfMBCharacters
	)		const

ToBSTR()

wchar_t* ToBSTR

(

)

const

Remarks

Returns the string in memory allocated by SysAllocString. Caller is responsible for freeing memory using SysFreeString.

FromBSTR()

static WStr FromBSTR ( const wchar_t *  string, size_t  length = (size_t) -1  )

static

ToCP()

MaxSDK::Util::MaxStringCastCP ToCP	(	UINT	cp,
		size_t *	length = NULL
	)		const

FromCP()

static WStr FromCP ( UINT  cp, const char *  string, size_t  length = (size_t) -1  )

static

ToACP()

MaxSDK::Util::MaxStringCast<char> ToACP

(

size_t *

length = NULL

)

const

FromACP()

static WStr FromACP ( const char *  string, size_t  length = (size_t) -1  )

static

ToUTF8()

MaxSDK::Util::MaxStringCastUTF8 ToUTF8

(

size_t *

length = NULL

)

const

FromUTF8()

static WStr FromUTF8 ( const char *  string, size_t  length = (size_t) -1  )

static

ToOLESTR()

MaxSDK::Util::MaxStringCast<WCHAR> ToOLESTR

(

size_t *

length = NULL

)

const

FromOLESTR()

static WStr FromOLESTR ( const wchar_t *  string, size_t  length = (size_t) -1  )

static

ToUTF16()

MaxSDK::Util::MaxStringCast<WCHAR> ToUTF16

(

size_t *

length = NULL

)

const

FromUTF16()

static WStr FromUTF16 ( const wchar_t *  string, size_t  length = (size_t) -1  )

static

ToUTF32()

MaxSDK::Util::MaxStringCast<unsigned int> ToUTF32

(

size_t *

length = NULL

)

const

FromUTF32()

static WStr FromUTF32 ( const unsigned int *  string, size_t  length = (size_t) -1  )

static

ToMaxString() [1/2]

MaxSDK::Util::MaxString ToMaxString

(

)

const

ToMaxString() [2/2]

void ToMaxString

(

MaxSDK::Util::MaxString &

)

const

FromMaxString()

static WStr FromMaxString ( MaxSDK::Util::MaxString &  string )

inlinestatic

{ return WStr(string); }

ToCStr()

CStr ToCStr

(

)

const

FromCStr()

static WStr FromCStr ( const CStr &  string )

static

ToWStr()

WStr ToWStr ( ) const

inline

{ return *this; }

FromWStr()

static WStr FromWStr ( const WStr &  string )

inlinestatic

{ return WStr(string); }

ToMCHAR()

const wchar_t* ToMCHAR ( size_t *  length = NULL ) const

inline

{ return ToUTF16(length); }

FromMCHAR()

static WStr FromMCHAR ( const wchar_t *  string, size_t  length = (size_t)-1  )

inlinestatic

{ return FromUTF16(string, length); }

ToMSTR()

WStr ToMSTR ( ) const

inline

{ return *this; }

FromMSTR()

static WStr FromMSTR ( const WStr &  string )

inlinestatic

{ return WStr(string); }

EndsWith() [1/2]

bool EndsWith	(	const WStr &	s,
		bool	caseSensitive = true
	)

Returns true if the string ends with s; otherwise returns false.

Parameters

s	The string to be searched.
caseSensitive	If it is true(default), the search is case sensitive; otherwise the search is case insensitive.

EndsWith() [2/2]

bool EndsWith	(	wchar_t	c,
		bool	caseSensitive = true
	)

Returns true if the string ends with c; otherwise returns false.

This function overloads EndsWith().

Parameters

c	The character to be searched.
caseSensitive	If it is true(default), the search is case sensitive; otherwise the search is case insensitive.

StartsWith() [1/2]

bool StartsWith	(	const WStr &	s,
		bool	caseSensitive = true
	)

Returns true if the string starts with s; otherwise returns false.

Parameters

s	The string to be searched.
caseSensitive	If it is true(default), the search is case sensitive; otherwise the search is case insensitive.

StartsWith() [2/2]

bool StartsWith	(	wchar_t	c,
		bool	caseSensitive = true
	)

Returns true if the string starts with c; otherwise returns false.

This function overloads StartsWith().

Parameters

c	The character to be searched.
caseSensitive	If it is true(default), the search is case sensitive; otherwise the search is case insensitive.

NumberOfLines()

size_t NumberOfLines

(

)

const

Returns the number of line feeds inside a string.

Replace()

size_t Replace	(	const wchar_t *	pFind,
		const wchar_t *	pReplaceBy,
		bool	firstOnly = false,
		size_t	startPosition = 0
	)

Replaces one substring with another in this string.

Parameters

pFind	The substring to be replaced.
pReplaceBy	The string the substring is to be replaced with.
firstOnly	If true, only first occurrence of 'from' is replaced, otherwise all occurrences are replaced
startPosition	The character position to start searching from

Returns

Returns the number of replacements made.