TStringView< CharType > Class Template Reference

#include <StringView.h>

Public Types
using	ElementType = CharType
using	ViewType = TStringView< CharType >

Public Member Functions
constexpr	TStringView ()=default
constexpr	TStringView (const CharType *InData UE_LIFETIMEBOUND)
constexpr	TStringView (const CharType *InData UE_LIFETIMEBOUND, int32 InSize)
template<UE::CCompatibleCharType< CharType > OtherCharType>
	TStringView (const OtherCharType *InData UE_LIFETIMEBOUND)
template<UE::CCompatibleCharType< CharType > OtherCharType>
constexpr	TStringView (const OtherCharType *InData UE_LIFETIMEBOUND, int32 InSize)
template<UE::CNotCVRefTo< ViewType > CharRangeType> requires (!std::is_pointer_v<std::decay_t<CharRangeType>> && UE::CCompatibleStringViewable<CharRangeType, CharType>)
constexpr	TStringView (const CharRangeType &InRange UE_LIFETIMEBOUND)
const CharType &	operator[] (int32 Index) const
constexpr const CharType *	GetData () const
constexpr SIZE_T	NumBytes () const
constexpr int32	Len () const
constexpr bool	IsEmpty () const
void	RemovePrefix (int32 CharCount)
void	RemoveSuffix (int32 CharCount)
void	Reset ()
int32	CopyString (CharType *Dest, int32 CharCount, int32 Position=0) const
ViewType	SubStr (int32 Position, int32 CharCount) const
ViewType	Left (int32 CharCount) const
ViewType	LeftChop (int32 CharCount) const
ViewType	Right (int32 CharCount) const
ViewType	RightChop (int32 CharCount) const
ViewType	Mid (int32 Position, int32 CharCount=MAX_int32) const
ViewType	TrimStartAndEnd () const
ViewType	TrimStart () const
ViewType	TrimEnd () const
void	LeftInline (int32 CharCount)
void	LeftChopInline (int32 CharCount)
void	RightInline (int32 CharCount)
void	RightChopInline (int32 CharCount)
void	MidInline (int32 Position, int32 CharCount=MAX_int32)
void	TrimStartAndEndInline ()
void	TrimStartInline ()
void	TrimEndInline ()
template<UE::CCharType OtherCharType>
bool	Equals (TStringView< OtherCharType > OtherView, ESearchCase::Type SearchCase=ESearchCase::CaseSensitive) const
template<UE::CStringViewable OtherRangeType>
bool	Equals (const OtherRangeType &Other, ESearchCase::Type SearchCase=ESearchCase::CaseSensitive) const
template<UE::CCharType OtherCharType>
bool	Equals (const OtherCharType *Other, ESearchCase::Type SearchCase=ESearchCase::CaseSensitive) const
template<UE::CStringViewable OtherRangeType>
int32	Compare (const OtherRangeType &Other, ESearchCase::Type SearchCase=ESearchCase::CaseSensitive) const
template<UE::CCharType OtherCharType>
int32	Compare (TStringView< OtherCharType > Other, ESearchCase::Type SearchCase=ESearchCase::CaseSensitive) const
template<UE::CCharType OtherCharType>
int32	Compare (const OtherCharType *Other, ESearchCase::Type SearchCase=ESearchCase::CaseSensitive) const
bool	StartsWith (CharType Prefix) const
bool	StartsWith (ViewType Prefix, ESearchCase::Type SearchCase=ESearchCase::IgnoreCase) const
bool	EndsWith (CharType Suffix) const
bool	EndsWith (ViewType Suffix, ESearchCase::Type SearchCase=ESearchCase::IgnoreCase) const
int32	Find (ViewType Search, int32 StartPosition=0, ESearchCase::Type SearchCase=ESearchCase::CaseSensitive) const
bool	Contains (ViewType Search, ESearchCase::Type SearchCase=ESearchCase::CaseSensitive) const
bool	FindChar (CharType Search, int32 &OutIndex) const
bool	FindLastChar (CharType Search, int32 &OutIndex) const
UE_FORCEINLINE_HINT bool	IsValidIndex (int32 Index) const
bool	UEOpEquals (TStringView Rhs) const
bool	UEOpLessThan (TStringView Rhs) const
template<UE::CConvertibleTo< TStringView > CharRangeType>
UE_REWRITE auto	UEOpEquals (CharRangeType &&Rhs) const
template<UE::CConvertibleTo< TStringView > CharRangeType>
UE_REWRITE auto	UEOpLessThan (CharRangeType &&Rhs)
template<UE::CConvertibleTo< TStringView > CharRangeType>
UE_REWRITE auto	UEOpGreaterThan (CharRangeType &&Rhs)
UE_REWRITE bool	UEOpEquals (const CharType *Rhs) const
constexpr const CharType *	begin () const
constexpr const CharType *	end () const
constexpr TReversePointerIterator< const CharType >	rbegin () const
constexpr TReversePointerIterator< const CharType >	rend () const

Protected Attributes
const CharType *	DataPtr = nullptr
int32	Size = 0

Friends
constexpr auto	GetNum (TStringView String)
uint32	GetTypeHash (TStringView View)

Detailed Description

template<UE::CCharType CharType>
class TStringView< CharType >

A string view is a non-owning view of a range of characters.

Ensure that the underlying string is valid for the lifetime of the string view.

Be careful when constructing a string view from a temporary. Make a local copy if necessary.

FStringView View = Object->GetPathName(); // Invalid

FString PathName = Object->GetPathName(); // Valid FStringView View = PathName;

void ProcessPath(FStringView Path); // Valid ProcessPath(Object->GetPathName());

A string view is implicitly constructible from null-terminated strings, from contiguous ranges of characters such as FString and TStringBuilder, and from literals such as TEXTVIEW("...").

A string view is cheap to copy and is meant to be passed by value. Avoid passing by reference.

A string view is not guaranteed to represent a null-terminated string.

Log or format a string view using UE_LOG(TEXT("%.*s"), View.Len(), View.GetData());

A string view is a good fit for function parameters where the function has no requirements for how the string is stored. A caller may use FString, FStringView, TStringBuilder, a char array, a null-terminated string, or any other type which can convert to a string view.

The UE::String namespace contains many functions that can operate on string views. Most of these functions can be found in String/___.h in Core.

void UseString(FStringView InString);
 
FString String(TEXT("ABC"));
const TCHAR* CString = *String;
TStringBuilder<16> StringBuilder;
StringBuilder.Append(TEXT("ABC"));
 
UseString(String);
UseString(CString);
UseString(StringBuilder);
UseString(TEXT("ABC"));
UseString(TEXTVIEW("ABC"));

Member Typedef Documentation

ElementType

template<UE::CCharType CharType>

using TStringView< CharType >::ElementType = CharType

ViewType

template<UE::CCharType CharType>

using TStringView< CharType >::ViewType = TStringView<CharType>

Constructor & Destructor Documentation

TStringView() [1/6]

template<UE::CCharType CharType>

constexpr TStringView< CharType >::TStringView ( )

constexprdefault

Construct an empty view.

TStringView() [2/6]

template<UE::CCharType CharType>

constexpr TStringView< CharType >::TStringView ( const CharType *InData  UE_LIFETIMEBOUND )

inlineconstexpr

Construct a view of the null-terminated string pointed to by InData.

TStringView() [3/6]

template<UE::CCharType CharType>

constexpr TStringView< CharType >::TStringView ( const CharType *InData  UE_LIFETIMEBOUND, int32  InSize  )

inlineconstexpr

Construct a view of InSize characters beginning at InData.

TStringView() [4/6]

template<UE::CCharType CharType>

template<UE::CCompatibleCharType< CharType > OtherCharType>

TStringView< CharType >::TStringView ( const OtherCharType *InData  UE_LIFETIMEBOUND )

inline

Construct a view of the null-terminated string pointed to by InData.

TStringView() [5/6]

template<UE::CCharType CharType>

template<UE::CCompatibleCharType< CharType > OtherCharType>

constexpr TStringView< CharType >::TStringView ( const OtherCharType *InData  UE_LIFETIMEBOUND, int32  InSize  )

inlineconstexpr

Construct a view of InSize characters beginning at InData.

TStringView() [6/6]

template<UE::CCharType CharType>

template<UE::CNotCVRefTo< ViewType > CharRangeType>
requires (!std::is_pointer_v<std::decay_t<CharRangeType>> && UE::CCompatibleStringViewable<CharRangeType, CharType>)

constexpr TStringView< CharType >::TStringView ( const CharRangeType &InRange  UE_LIFETIMEBOUND )

inlineconstexpr

Construct a view from a contiguous range of characters, such as FString or TStringBuilder.

Member Function Documentation

begin()

template<UE::CCharType CharType>

constexpr const CharType * TStringView< CharType >::begin ( ) const

inlineconstexpr

DO NOT USE DIRECTLY STL-like iterators to enable range-based for loop support.

Compare() [1/3]

template<UE::CCharType CharType>

template<UE::CCharType OtherCharType>

int32 TStringView< CharType >::Compare ( const OtherCharType *  Other, ESearchCase::Type  SearchCase = ESearchCase::CaseSensitive  ) const

inline

Compare this view with a null-terminated string.

Parameters

Other	A null-terminated string that is comparable with the character type of this view.
SearchCase	Whether the comparison should ignore case.

Returns

0 is equal, negative if this view is less, positive if this view is greater.

Compare() [2/3]

template<UE::CCharType CharType>

template<UE::CStringViewable OtherRangeType>

int32 TStringView< CharType >::Compare ( const OtherRangeType &  Other, ESearchCase::Type  SearchCase = ESearchCase::CaseSensitive  ) const

inline

Compare this view with a character range.

Parameters

Other	A character range that is comparable with the character type of this view.
SearchCase	Whether the comparison should ignore case.

Returns

0 is equal, negative if this view is less, positive if this view is greater.

Compare() [3/3]

template<UE::CCharType CharType>

template<UE::CCharType OtherCharType>

int32 TStringView< CharType >::Compare ( TStringView< OtherCharType >  Other, ESearchCase::Type  SearchCase = ESearchCase::CaseSensitive  ) const

inline

Compare this view with a string view.

Parameters

Other	A string view that is comparable with the character type of this view.
SearchCase	Whether the comparison should ignore case.

Returns

0 is equal, negative if this view is less, positive if this view is greater.

Contains()

template<UE::CCharType CharType>

bool TStringView< CharType >::Contains ( ViewType  Search, ESearchCase::Type  SearchCase = ESearchCase::CaseSensitive  ) const

inline

Returns whether this view contains the specified substring.

Parameters

Search	Text to search for
SearchCase	Indicates whether the search is case sensitive or not

Returns

True if the view contains the search string, otherwise false.

CopyString()

template<UE::CCharType CharType>

int32 TStringView< CharType >::CopyString ( CharType *  Dest, int32  CharCount, int32  Position = 0  ) const

inline

Copy characters from the view into a destination buffer without null termination.

Parameters

Dest	Buffer to write into. Must have space for at least CharCount characters.
CharCount	The maximum number of characters to copy.
Position	The offset into the view from which to start copying.

Returns

The number of characters written to the destination buffer.

end()

template<UE::CCharType CharType>

constexpr const CharType * TStringView< CharType >::end ( ) const

inlineconstexpr

EndsWith() [1/2]

template<UE::CCharType CharType>

bool TStringView< CharType >::EndsWith ( CharType  Suffix ) const

inline

Returns whether this view ends with the suffix character compared case-sensitively.

EndsWith() [2/2]

template<UE::CCharType CharType>

bool TStringView< CharType >::EndsWith ( ViewType  Suffix, ESearchCase::Type  SearchCase = ESearchCase::IgnoreCase  ) const

inline

Returns whether this view ends with the suffix with optional case sensitivity.

Equals() [1/3]

template<UE::CCharType CharType>

template<UE::CCharType OtherCharType>

bool TStringView< CharType >::Equals ( const OtherCharType *  Other, ESearchCase::Type  SearchCase = ESearchCase::CaseSensitive  ) const

inline

Check whether this view is equivalent to a string view.

Parameters

Other	A string that is comparable with the character type of this view.
SearchCase	Whether the comparison should ignore case.

Equals() [2/3]

template<UE::CCharType CharType>

template<UE::CStringViewable OtherRangeType>

bool TStringView< CharType >::Equals ( const OtherRangeType &  Other, ESearchCase::Type  SearchCase = ESearchCase::CaseSensitive  ) const

inline

Check whether this view is equivalent to a character range.

Parameters

Other	A character range that is comparable with the character type of this view.
SearchCase	Whether the comparison should ignore case.

Equals() [3/3]

template<UE::CCharType CharType>

template<UE::CCharType OtherCharType>

bool TStringView< CharType >::Equals ( TStringView< OtherCharType >  OtherView, ESearchCase::Type  SearchCase = ESearchCase::CaseSensitive  ) const

inline

Check whether this view is equivalent to another view.

Parameters

OtherView	A string view that is comparable with the character type of this view.
SearchCase	Whether the comparison should ignore case.

Returns

0 is equal, negative if this view is less, positive if this view is greater.

Find()

template<UE::CCharType CharType>

int32 TStringView< CharType >::Find ( ViewType  Search, int32  StartPosition = 0, ESearchCase::Type  SearchCase = ESearchCase::CaseSensitive  ) const

inline

Search the view for the first occurrence of a search string.

Parameters

Search	The string to search for. Comparison is lexicographic.
StartPosition	The character position to start searching from.
SearchCase	Indicates whether the search is case sensitive or not

Returns

The index of the first occurrence of the search string if found, otherwise INDEX_NONE.

FindChar()

template<UE::CCharType CharType>

bool TStringView< CharType >::FindChar ( CharType  Search, int32 &  OutIndex  ) const

inline

Search the view for the first occurrence of a character.

Parameters

Search	The character to search for. Comparison is lexicographic.
OutIndex	[out] The position at which the character was found, or INDEX_NONE if not found.

Returns

True if the character was found in the view, otherwise false.

FindLastChar()

template<UE::CCharType CharType>

bool TStringView< CharType >::FindLastChar ( CharType  Search, int32 &  OutIndex  ) const

inline

Search the view for the last occurrence of a character.

Parameters

Search	The character to search for. Comparison is lexicographic.
OutIndex	[out] The position at which the character was found, or INDEX_NONE if not found.

Returns

True if the character was found in the view, otherwise false.

GetData()

template<UE::CCharType CharType>

constexpr const CharType * TStringView< CharType >::GetData ( ) const

inlineconstexpr

Returns a pointer to the start of the view. This is NOT guaranteed to be null-terminated!

IsEmpty()

template<UE::CCharType CharType>

constexpr bool TStringView< CharType >::IsEmpty ( ) const

inlineconstexpr

Returns whether the string view is empty.

IsValidIndex()

template<UE::CCharType CharType>

UE_FORCEINLINE_HINT bool TStringView< CharType >::IsValidIndex ( int32  Index ) const

inline

Tests if index is valid, i.e. greater than or equal to zero, and less than the number of characters in the string view.

Parameters

Index

Index to test.

Returns

True if index is valid. False otherwise.

Left()

template<UE::CCharType CharType>

TStringView< CharType > TStringView< CharType >::Left ( int32  CharCount ) const

inline

Returns the left-most part of the view by taking the given number of characters from the left.

LeftChop()

template<UE::CCharType CharType>

TStringView< CharType > TStringView< CharType >::LeftChop ( int32  CharCount ) const

inline

Returns the left-most part of the view by chopping the given number of characters from the right.

LeftChopInline()

template<UE::CCharType CharType>

void TStringView< CharType >::LeftChopInline ( int32  CharCount )

inline

Modifies the view by chopping the given number of characters from the right.

LeftInline()

template<UE::CCharType CharType>

void TStringView< CharType >::LeftInline ( int32  CharCount )

inline

Modifies the view to be the given number of characters from the left.

Len()

template<UE::CCharType CharType>

constexpr int32 TStringView< CharType >::Len ( ) const

inlineconstexpr

Returns the length of the string view.

Mid()

template<UE::CCharType CharType>

TStringView< CharType > TStringView< CharType >::Mid ( int32  Position, int32  CharCount = MAX_int32  ) const

inline

Returns the middle part of the view by taking up to the given number of characters from the given position.

MidInline()

template<UE::CCharType CharType>

void TStringView< CharType >::MidInline ( int32  Position, int32  CharCount = MAX_int32  )

inline

Modifies the view to be the middle part by taking up to the given number of characters from the given position.

NumBytes()

template<UE::CCharType CharType>

constexpr SIZE_T TStringView< CharType >::NumBytes ( ) const

inlineconstexpr

Returns

Number of bytes used for the characters in the string view

operator[]()

template<UE::CCharType CharType>

const CharType & TStringView< CharType >::operator[] ( int32  Index ) const

inline

Access the character at the given index in the view.

rbegin()

template<UE::CCharType CharType>

constexpr TReversePointerIterator< const CharType > TStringView< CharType >::rbegin ( ) const

inlineconstexpr

RemovePrefix()

template<UE::CCharType CharType>

void TStringView< CharType >::RemovePrefix ( int32  CharCount )

inline

Modifies the view to remove the given number of characters from the start.

RemoveSuffix()

template<UE::CCharType CharType>

void TStringView< CharType >::RemoveSuffix ( int32  CharCount )

inline

Modifies the view to remove the given number of characters from the end.

rend()

template<UE::CCharType CharType>

constexpr TReversePointerIterator< const CharType > TStringView< CharType >::rend ( ) const

inlineconstexpr

Reset()

template<UE::CCharType CharType>

void TStringView< CharType >::Reset ( )

inline

Resets to an empty view

Right()

template<UE::CCharType CharType>

TStringView< CharType > TStringView< CharType >::Right ( int32  CharCount ) const

inline

Returns the right-most part of the view by taking the given number of characters from the right.

RightChop()

template<UE::CCharType CharType>

TStringView< CharType > TStringView< CharType >::RightChop ( int32  CharCount ) const

inline

Returns the right-most part of the view by chopping the given number of characters from the left.

RightChopInline()

template<UE::CCharType CharType>

void TStringView< CharType >::RightChopInline ( int32  CharCount )

inline

Modifies the view by chopping the given number of characters from the left.

RightInline()

template<UE::CCharType CharType>

void TStringView< CharType >::RightInline ( int32  CharCount )

inline

Modifies the view to be the given number of characters from the right.

StartsWith() [1/2]

template<UE::CCharType CharType>

bool TStringView< CharType >::StartsWith ( CharType  Prefix ) const

inline

Returns whether this view starts with the prefix character compared case-sensitively.

StartsWith() [2/2]

template<UE::CCharType CharType>

bool TStringView< CharType >::StartsWith ( ViewType  Prefix, ESearchCase::Type  SearchCase = ESearchCase::IgnoreCase  ) const

inline

Returns whether this view starts with the prefix with optional case sensitivity.

SubStr()

template<UE::CCharType CharType>

ViewType TStringView< CharType >::SubStr ( int32  Position, int32  CharCount  ) const

inline

Alias for Mid.

TrimEnd()

template<UE::CCharType CharType>

TStringView< CharType > TStringView< CharType >::TrimEnd ( ) const

inline

Returns the left part of the view before any whitespace at the end.

TrimEndInline()

template<UE::CCharType CharType>

void TStringView< CharType >::TrimEndInline ( )

inline

Modifies the view to be the left part before any whitespace at the end.

TrimStart()

template<UE::CCharType CharType>

TStringView< CharType > TStringView< CharType >::TrimStart ( ) const

inline

Returns the right part of the view after any whitespace at the start.

TrimStartAndEnd()

template<UE::CCharType CharType>

TStringView< CharType > TStringView< CharType >::TrimStartAndEnd ( ) const

inline

Returns the middle part of the view between any whitespace at the start and end.

TrimStartAndEndInline()

template<UE::CCharType CharType>

void TStringView< CharType >::TrimStartAndEndInline ( )

inline

Modifies the view to be the middle part between any whitespace at the start and end.

TrimStartInline()

template<UE::CCharType CharType>

void TStringView< CharType >::TrimStartInline ( )

inline

Modifies the view to be the right part after any whitespace at the start.

UEOpEquals() [1/3]

template<UE::CCharType CharType>

template<UE::CConvertibleTo< TStringView > CharRangeType>

UE_REWRITE auto TStringView< CharType >::UEOpEquals ( CharRangeType &&  Rhs ) const

inline

UEOpEquals() [2/3]

template<UE::CCharType CharType>

UE_REWRITE bool TStringView< CharType >::UEOpEquals ( const CharType *  Rhs ) const

inline

UEOpEquals() [3/3]

template<UE::CCharType CharType>

bool TStringView< CharType >::UEOpEquals ( TStringView< CharType >  Rhs ) const

inline

UEOpGreaterThan()

template<UE::CCharType CharType>

template<UE::CConvertibleTo< TStringView > CharRangeType>

UE_REWRITE auto TStringView< CharType >::UEOpGreaterThan ( CharRangeType &&  Rhs )

inline

UEOpLessThan() [1/2]

template<UE::CCharType CharType>

template<UE::CConvertibleTo< TStringView > CharRangeType>

UE_REWRITE auto TStringView< CharType >::UEOpLessThan ( CharRangeType &&  Rhs )

inline

UEOpLessThan() [2/2]

template<UE::CCharType CharType>

bool TStringView< CharType >::UEOpLessThan ( TStringView< CharType >  Rhs ) const

inline

Friends And Related Symbol Documentation

GetNum

template<UE::CCharType CharType>

constexpr auto GetNum ( TStringView< CharType >  String )

friend

GetTypeHash

template<UE::CCharType CharType>

uint32 GetTypeHash ( TStringView< CharType >  View )

friend

Case insensitive string hash function.

Member Data Documentation

DataPtr

template<UE::CCharType CharType>

const CharType* TStringView< CharType >::DataPtr = nullptr

protected

Size

template<UE::CCharType CharType>

int32 TStringView< CharType >::Size = 0

protected

---

The documentation for this class was generated from the following files:

• Engine/Source/Runtime/Core/Public/Containers/StringFwd.h
• Engine/Source/Runtime/Core/Public/Containers/StringView.h