QAnyStringView 类

QAnyStringView 类提供 Latin-1、UTF-8 或 UTF-16 的统一字符串视图，采用只读子集的 QString API. 更多...

头：	`#include <QAnyStringView>`
CMake:	`find_package(Qt6 REQUIRED COMPONENTS Core)` `target_link_libraries(mytarget PRIVATE Qt6::Core)`
qmake:	`QT += core`
Since:	Qt 6.0

此类 强烈可比较 .

此类 强烈可比较 采用 char16_t， QChar , const char16_t *, const char *, QByteArray , QByteArrayView , QString , QStringView , QUtf8StringView ，和 QLatin1StringView .

注意： 此类的所有函数可重入 .

公共类型

	difference_type
	size_type

公共函数

	QAnyStringView ()
	QAnyStringView (const Char & ch )
	QAnyStringView (const Char (&)[N] string )
	QAnyStringView (const Char * str )
	QAnyStringView (const Container & str )
	QAnyStringView (const QByteArray & str )
	QAnyStringView (const QString & str )
	QAnyStringView (std::nullptr_t)
	QAnyStringView (const Char * first , const Char * last )
	QAnyStringView (const Char * str , qsizetype len )
QChar	back () const
`(从 6.5 起)` void	chop (qsizetype n )
`(从 6.5 起)` QAnyStringView	chopped (qsizetype n ) const
const void *	data () const
bool	empty () const
`(从 6.5 起)` QAnyStringView	first (qsizetype n ) const
QChar	front () const
bool	isEmpty () const
bool	isNull () const
`(从 6.5 起)` QAnyStringView	last (qsizetype n ) const
qsizetype	length () const
`(从 6.8 起)` qsizetype	max_size () const
qsizetype	size () const
qsizetype	size_bytes () const
`(从 6.8 起)` QAnyStringView &	slice (qsizetype pos , qsizetype n )
`(从 6.8 起)` QAnyStringView &	slice (qsizetype pos )
`(从 6.5 起)` QAnyStringView	sliced (qsizetype pos ) const
`(从 6.5 起)` QAnyStringView	sliced (qsizetype pos , qsizetype n ) const
QString	toString () const
`(从 6.5 起)` void	truncate (qsizetype n )
decltype(auto)	visit (Visitor && v ) const

静态公共成员

int	compare (QAnyStringView lhs , QAnyStringView rhs , Qt::CaseSensitivity cs = Qt::CaseSensitive)
QAnyStringView	fromArray (const Char (&)[Size] string )

bool	operator!= (const QAnyStringView & lhs , const QAnyStringView & rhs )
bool	operator< (const QAnyStringView & lhs , const QAnyStringView & rhs )
`(从 6.7 起)` QDebug	operator<< (QDebug d , QAnyStringView s )
bool	operator<= (const QAnyStringView & lhs , const QAnyStringView & rhs )
bool	operator== (const QAnyStringView & lhs , const QAnyStringView & rhs )
bool	operator> (const QAnyStringView & lhs , const QAnyStringView & rhs )
bool	operator>= (const QAnyStringView & lhs , const QAnyStringView & rhs )

详细描述

QAnyStringView 引用它不拥有的字符串连续部分。它充当所有种类字符串的接口类型，不需要构造 QString 首先。

不像 QStringView and QUtf8StringView , QAnyStringView can hold strings of any of the following encodings: UTF-8, UTF-16, and Latin-1. The latter is supported because Latin-1, unlike UTF-8, can be efficiently compared to UTF-16 data: a length mismatch already means the strings cannot be equal. This is not true for UTF-8/UTF-16 comparisons, because UTF-8 is a variable-length encoding.

The string may be represented as an array (or an array-compatible data-structure such as QString , std::basic_string, etc.) of char , char8_t , QChar , ushort , char16_t or (on platforms, such as Windows, where it is a 16-bit type) wchar_t .

QAnyStringView is designed as an interface type; its main use-case is as a function parameter type. When QAnyStringViews are used as automatic variables or data members, care must be taken to ensure that the referenced string data (for example, owned by a QString ) outlives the QAnyStringView on all code paths, lest the string view ends up referencing deleted data.

例如，

QAnyStringView str = funcReturningQString(); // return value is a temp

would leave str referencing the deleted temporary (which constitutes undefined behavior). This is particularly true for the single-character constructors:

QAnyStringView ch = u' '; // u' ' is a temporary
// oops, ch references deleted temporary

In both cases, the solution is to "pin" the temporary to an lvalue and only then create a QAnyStringView from it:

const auto r = funcReturningQString();
QAnyStringView str = r; // ok, `r` outlives `str`
const auto sp = u' ';
QAnyStringView ch = sp; // ok, `sp` outlives `ch`

However, using QAnyStringView as the interface type that it is intended to be is always safe, provided the called function's documentation is not asking for a longer lifetime:

void func(QAnyStringView s);
func(u' ');
func(functionReturningQString());

This is why QAnyStringView supports these conversions in the first place.

When used as an interface type, QAnyStringView allows a single function to accept a wide variety of string data sources. One function accepting QAnyStringView thus replaces five function overloads (taking QString , (const QChar*, qsizetype) , QUtf8StringView , QLatin1StringView (but see above), and QChar ), while at the same time enabling even more string data sources to be passed to the function, such as u8"Hello World" ， char8_t 字符串文字。

Like elsewhere in Qt, QAnyStringView assumes char data is encoded in UTF-8, unless it is presented as a QLatin1StringView .

Since Qt 6.4, however, UTF-8 string literals that are pure US-ASCII are automatically stored as Latin-1. This is a compile-time check with no runtime overhead. The feature requires compiling in C++20, or with a recent GCC.

QAnyStringViews should be passed by value, not by reference-to-const:

    void myfun1(QAnyStringView sv);        // preferred
    void myfun2(const QAnyStringView &sv); // compiles and works, but slower

QAnyStringView can also be used as the return value of a function, but this is not recommended. QUtf8StringView or QStringView are better suited as function return values. If you call a function returning QAnyStringView, take extra care to not keep the QAnyStringView around longer than the function promises to keep the referenced string data alive. If in doubt, obtain a strong reference to the data by calling toString () to convert the QAnyStringView into a QString .

QAnyStringView 为 文字类型 .

兼容字符类型

QAnyStringView 接受各种字符类型的字符串：

char (有符号和无符号两者)
char8_t (仅 C++20)
char16_t
wchar_t (在此是 16 位类型，如 Windows)
ushort
QChar

The 8-bit character types are interpreted as UTF-8 data (except when presented as a QLatin1StringView ) while the 16-bit character types are interpreted as UTF-16 data in host byte order (the same as QString ).

The following character types are only supported by the single-character constructor:

QLatin1Char
QChar::SpecialCharacter
char32_t

These character types are internally decomposed into a UTF-16 sequence (using QChar::fromUcs4 () for the last).

大小和子字符串

All sizes and positions in QAnyStringView functions are in the encoding's code units (that is, UTF-16 surrogate pairs count as two for the purposes of these functions, the same as in QString , and UTF-8 multibyte sequences count as two, three or four, depending on their length).

另请参阅 QUtf8StringView and QStringView .

成员类型文档编制

QAnyStringView:: difference_type

别名化的 std::ptrdiff_t 。为兼容 STL (标准模板库) 提供。

QAnyStringView:: size_type

别名化的 qsizetype。为兼容 STL (标准模板库) 提供。

成员函数文档编制

`[constexpr noexcept]` QAnyStringView:: QAnyStringView ()

构造 null 字符串视图。

另请参阅 isNull ().

`[constexpr noexcept]` template <typename Char, QAnyStringView::if_compatible_char<Char> = true> QAnyStringView:: QAnyStringView (const Char & ch )

Constructs a string view on the single character ch . The length is usually 1 (but see below).

In general, you must assume that a QAnyStringView thus created will start to reference stale data at the end of the full-expression , when temporaries are deleted. That means that using it to pass a single character to a QAnyStringView-taking function is ok and safe (as long as the function documentation doesn't ask for a lifetime longer than the initial call):

int to_int(QAnyStringView);
int res = to_int(u'9'); // OK, data stays around for the duration of the call

But keeping the object around longer is undefined behavior:

QAnyStringView ch = u'9';
int res = to_int(ch); // (silent) ERROR: ch references deleted data

If you need this, prefer

const auto nine = u'9';
QAnyStringView ch(nine); // ok, references `nine`, which outlives `ch`
int res = to_int(ch); // 9

The above is true for all directly supported 兼容字符类型 .

若 ch is not one of these types, but merely converts to QChar ，如 QChar::SpecialCharacter or QLatin1Char , the QAnyStringView will bind to a temporary object that will have been deleted at the end of the full expression, just like in the second example.

若 ch cannot be represented in a single UTF-16 code unit (e.g. because it's a char32_t value), this constructor decomposes ch into two UFT-16 code units. The resulting QAnyStringView will have a size () of 2 in that case, and the temporary buffer in which the decomposition is stored is deleted at the end of the full-expression, similar to

[](char32_t ch, auto &&tmp = QChar::fromUcs4(ch)) {
    return QAnyStringView(tmp);
}

The equivalent safe version in this case would be

const auto decomposed = QChar::fromUcs4(ch);
QAnyStringView ch(decomposed);

另请参阅 QChar::fromUcs4 () 和兼容字符类型 .

`[constexpr noexcept]` template <typename Char, size_t N> QAnyStringView:: QAnyStringView (const Char (&)[ N ] string )

构造字符串视图按字符串文字 string 。视图覆盖数组，直到第 1 个 Char(0) 被遇到，或 N ，以先到的为准。若需要完整数组，使用 fromArray () 代替。

string 必须在此字符串视图对象的寿命内保持有效。

This constructor only participates in overload resolution if string is an actual array and Char is a compatible character type.

另请参阅 兼容字符类型 .

`[constexpr noexcept]` template <typename Char> QAnyStringView:: QAnyStringView (const Char * str )

构造字符串视图对 str . The length is determined by scanning for the first Char(0) .

str 必须在此字符串视图对象的寿命内保持有效。

传递 nullptr as str 是安全的且结果在 null 字符串视图中。

This constructor only participates in overload resolution if str is not an array and if Char is a compatible character type.

另请参阅 isNull () 和兼容字符类型 .

`[constexpr noexcept]` template <typename Container, QAnyStringView::if_compatible_container<Container> = true> QAnyStringView:: QAnyStringView (const 容器 & str )

构造字符串视图对 str 。长度取自 std::size(str) .

std::data(str) 必须在此字符串视图对象的寿命内保持有效。

This constructor only participates in overload resolution if Container is a container with a compatible character type as value_type .

The string view will be empty if and only if std::size(str) == 0 . It is unspecified whether this constructor can result in a null string view ( std::data(str) would have to return nullptr for this).

另请参阅 isNull () 和 isEmpty ().

`[noexcept]` QAnyStringView:: QAnyStringView (const QByteArray & str )

构造字符串视图对 str . The data in str is interpreted as UTF-8.

str.data() 必须在此字符串视图对象的寿命内保持有效。

字符串视图将为 null 当且仅当 str.isNull() .

`[noexcept]` QAnyStringView:: QAnyStringView (const QString & str )

构造字符串视图对 str .

str.data() 必须在此字符串视图对象的寿命内保持有效。

字符串视图将为 null 当且仅当 str.isNull() .

`[constexpr noexcept]` QAnyStringView:: QAnyStringView ( std::nullptr_t )

构造 null 字符串视图。

另请参阅 isNull ().

`[constexpr]` template <typename Char, QAnyStringView::if_compatible_char<Char> = true> QAnyStringView:: QAnyStringView (const Char * first , const Char * last )

构造字符串视图对 first 按长度 ( last - first ).

范围 [first,last) 必须在此字符串视图对象的寿命内保持有效。

传递 nullptr as first 是安全的若 last is nullptr , too, and results in a null string view.

行为未定义若 last precedes first ，或 first is nullptr and last is not.

This constructor only participates in overload resolution if Char is a compatible character type.

另请参阅 isNull () 和兼容字符类型 .

`[constexpr]` template <typename Char, QAnyStringView::if_compatible_char<Char> = true> QAnyStringView:: QAnyStringView (const Char * str , qsizetype len )

构造字符串视图对 str 按长度 len .

范围 [str,len) 必须在此字符串视图对象的寿命内保持有效。

传递 nullptr as str 是安全的若 len is 0, too, and results in a null string view.

行为未定义若 len is negative or, when positive, if str is nullptr .

This constructor only participates in overload resolution if Char is a compatible character type.

另请参阅 isNull () 和兼容字符类型 .

`[constexpr]` QChar QAnyStringView:: back () const

返回字符串视图中的最后一个字符。

此函数为兼容 STL (标准模板库) 提供。

警告： 在空字符串视图调用此函数，将构成未定义行为。

另请参阅 front () 和大小和子字符串 .

`[constexpr, since 6.5]` void QAnyStringView:: chop ( qsizetype n )

截取此字符串视图按 n 代码点。

如同 *this = first(size() - n) .

注意： 行为未定义当 n < 0 or n > size ().

该函数在 Qt 6.5 引入。

另请参阅 sliced (), first (), last (), chopped (), truncate (), slice ()，和大小和子字符串 .

`[constexpr, since 6.5]` QAnyStringView QAnyStringView:: chopped ( qsizetype n ) const

返回子字符串长度 size () - n 起始于此对象的开头。

如同 first(size() - n) .

注意： 行为未定义当 n < 0 or n > size ().

该函数在 Qt 6.5 引入。

另请参阅 sliced (), first (), last (), chop (), truncate (), slice ()，和大小和子字符串 .

`[static noexcept]` int QAnyStringView:: compare ( QAnyStringView lhs , QAnyStringView rhs , Qt::CaseSensitivity cs = Qt::CaseSensitive)

比较字符串视图 lhs with the string view rhs 并返回负整数若 lhs 小于 rhs ，正整数若大于 rhs ，和 0 若它们相等。

若 cs is Qt::CaseSensitive (the default), the comparison is case sensitive; otherwise the comparison is case-insensitive.

另请参阅 operator== (), operator< ()，和 operator> ().

`[constexpr noexcept]` const void *QAnyStringView:: data () const

Returns a const pointer to the first character in the string view.

注意： The character array represented by the return value is not null-terminated.

另请参阅 size_bytes ().

`[constexpr noexcept]` bool QAnyStringView:: empty () const

Returns whether this string view is empty - that is, whether size() == 0 .

此函数为兼容 STL (标准模板库) 提供。

另请参阅 isEmpty (), isNull ()，和 size ().

`[constexpr, since 6.5]` QAnyStringView QAnyStringView:: first ( qsizetype n ) const

Returns a string view that contains the first n code points of this string view.

注意： 行为未定义当 n < 0 or n > size ().

该函数在 Qt 6.5 引入。

另请参阅 last (), sliced (), chopped (), chop (), truncate (), slice ()，和大小和子字符串 .

`[static constexpr noexcept]` template <typename Char, size_t Size, QAnyStringView::if_compatible_char<Char> = true> QAnyStringView QAnyStringView:: fromArray (const Char (&)[ Size ] string )

Constructs a string view on the full character string literal string , including any trailing Char(0) . If you don't want the null-terminator included in the view then you can chop () it off when you are certain it is at the end. Alternatively you can use the constructor overload taking an array literal which will create a view up to, but not including, the first null-terminator in the data.

string 必须在此字符串视图对象的寿命内保持有效。

This function will work with any array literal if Char is a compatible character type. The compatible character types are: QChar , ushort , char16_t and (on platforms, such as Windows, where it is a 16-bit type) wchar_t .

`[constexpr]` QChar QAnyStringView:: front () const

Returns the first character in the string view.

此函数为兼容 STL (标准模板库) 提供。

警告： 在空字符串视图调用此函数，将构成未定义行为。

另请参阅 back () 和大小和子字符串 .

`[constexpr noexcept]` bool QAnyStringView:: isEmpty () const

Returns whether this string view is empty - that is, whether size() == 0 .

This function is provided for compatibility with other Qt containers.

另请参阅 empty (), isNull ()，和 size ().

`[constexpr noexcept]` bool QAnyStringView:: isNull () const

Returns whether this string view is null - that is, whether data() == nullptr .

This functions is provided for compatibility with other Qt containers.

另请参阅 empty (), isEmpty ()，和 size ().

`[constexpr, since 6.5]` QAnyStringView QAnyStringView:: last ( qsizetype n ) const

Returns a string view that contains the last n code points of this string view.

注意： 行为未定义当 n < 0 or n > size ().

该函数在 Qt 6.5 引入。

另请参阅 first (), sliced (), chopped (), chop (), truncate (), slice ()，和大小和子字符串 .

`[constexpr noexcept]` qsizetype QAnyStringView:: length () const

如同 size ().

This function is provided for compatibility with other Qt containers.

另请参阅 size ().

`[constexpr noexcept, since 6.8]` qsizetype QAnyStringView:: max_size () const

此函数为兼容 STL (标准模板库) 提供。

It returns the maximum number of elements that the string view can theoretically represent. In practice, the number can be much smaller, limited by the amount of memory available to the system.

注意： The returned value is calculated based on the currently used character type, so calling this function on two different views may return different results.

该函数在 Qt 6.8 引入。

`[constexpr noexcept]` qsizetype QAnyStringView:: size () const

Returns the size of this string view, in the encoding's code points.

另请参阅 empty (), isEmpty (), isNull (), size_bytes ()，和大小和子字符串 .

`[constexpr noexcept]` qsizetype QAnyStringView:: size_bytes () const

Returns the size of this string view, but in bytes, not code-points.

You can use this function together with data () for hashing or serialization.

此函数为兼容 STL (标准模板库) 提供。

另请参阅 size () 和 data ().

`[constexpr, since 6.8]` QAnyStringView &QAnyStringView:: slice ( qsizetype pos , qsizetype n )

Modifies this string view to start at position pos , extending for n 代码点。

注意： 行为未定义当 pos < 0, n < 0, or pos + n > size ().

该函数在 Qt 6.8 引入。

另请参阅 sliced (), first (), last (), chopped (), chop (), truncate ()，和大小和子字符串 .

`[constexpr, since 6.8]` QAnyStringView &QAnyStringView:: slice ( qsizetype pos )

这是重载函数。

Modifies this string view to start at position pos , extending to its end.

注意： 行为未定义当 pos < 0 or pos > size ().

该函数在 Qt 6.8 引入。

另请参阅 sliced (), first (), last (), chopped (), chop (), truncate ()，和大小和子字符串 .

`[constexpr, since 6.5]` QAnyStringView QAnyStringView:: sliced ( qsizetype pos ) const

Returns a string view starting at position pos in this object, and extending to its end.

注意： 行为未定义当 pos < 0 or pos > size ().

该函数在 Qt 6.5 引入。

另请参阅 first (), last (), chopped (), chop (), truncate (), slice ()，和大小和子字符串 .

`[constexpr, since 6.5]` QAnyStringView QAnyStringView:: sliced ( qsizetype pos , qsizetype n ) const

Returns a string view containing n code points of this string view, starting at position pos .

注意： 行为未定义当 pos < 0, n < 0, or pos + n > size ().

该函数在 Qt 6.5 引入。

另请参阅 first (), last (), chopped (), chop (), truncate (), slice ()，和大小和子字符串 .

QString QAnyStringView:: toString () const

Returns a deep copy of this string view's data as a QString .

The return value will be a null QString if and only if this string view is null.

`[constexpr, since 6.5]` void QAnyStringView:: truncate ( qsizetype n )

Truncates this string view to n 代码点。

如同 *this = first(n) .

注意： 行为未定义当 n < 0 or n > size ().

该函数在 Qt 6.5 引入。

另请参阅 sliced (), first (), last (), chopped (), chop ()，和大小和子字符串 .

`[constexpr]` template <typename Visitor> decltype ( auto ) QAnyStringView:: visit ( Visitor && v ) const

调用 v with either a QUtf8StringView , QLatin1String ，或 QStringView , depending on the encoding of the string data this string-view references.

This is how most functions taking QAnyStringView fork off into per-encoding functions:

void processImpl(QLatin1String s) { ~~~ }
void processImpl(QUtf8StringView s) { ~~~ }
void processImpl(QStringView s) { ~~~ }
void process(QAnyStringView s)
{
    s.visit([](auto s) { processImpl(s); });
}

Here, we're reusing the same name, s , for both the QAnyStringView object, as well as the lambda's parameter. This is idiomatic code and helps track the identity of the objects through visit() calls, for example in more complex situations such as

bool equal(QAnyStringView lhs, QAnyStringView rhs)
{
    // assuming operator==(QAnyStringView, QAnyStringView) didn't, yet, exist:
    return lhs.visit([rhs](auto lhs) {
        rhs.visit([lhs](auto rhs) {
            return lhs == rhs;
        });
    });
}

visit() requires that all lambda instantiations have the same return type. If they differ, you get a compile error, even if there is a common type. To fix, you can use explicit return types on the lambda, or cast in the return statements:

// wrong:
QAnyStringView firstHalf(QAnyStringView input)
{
    return input.visit([](auto input) {   // ERROR: lambdas return different types
        return input.sliced(0, input.size() / 2);
    });
}
// correct:
QAnyStringView firstHalf(QAnyStringView input)
{
    return input.visit([](auto input) -> QAnyStringView { // OK, explicit return type
        return input.sliced(0, input.size() / 2);
    });
}
// also correct:
QAnyStringView firstHalf(QAnyStringView input)
{
    return input.visit([](auto input) {
        return QAnyStringView(input.sliced(0, input.size() / 2)); // OK, cast to common type
    });
}

QAnyStringView 类

公共类型

公共函数

静态公共成员

相关非成员

详细描述

兼容字符类型

大小和子字符串

成员类型文档编制

QAnyStringView:: difference_type

QAnyStringView:: size_type

成员函数文档编制

[constexpr noexcept] QAnyStringView:: QAnyStringView ()

[constexpr noexcept] template <typename Char, QAnyStringView::if_compatible_char<Char> = true> QAnyStringView:: QAnyStringView (const Char & ch )

[constexpr noexcept] template <typename Char, size_t N> QAnyStringView:: QAnyStringView (const Char (&)[ N ] string )

[constexpr noexcept] template <typename Char> QAnyStringView:: QAnyStringView (const Char * str )

[constexpr noexcept] template <typename Container, QAnyStringView::if_compatible_container<Container> = true> QAnyStringView:: QAnyStringView (const 容器 & str )

[noexcept] QAnyStringView:: QAnyStringView (const QByteArray & str )

[noexcept] QAnyStringView:: QAnyStringView (const QString & str )

[constexpr noexcept] QAnyStringView:: QAnyStringView ( std::nullptr_t )

[constexpr] template <typename Char, QAnyStringView::if_compatible_char<Char> = true> QAnyStringView:: QAnyStringView (const Char * first , const Char * last )

[constexpr] template <typename Char, QAnyStringView::if_compatible_char<Char> = true> QAnyStringView:: QAnyStringView (const Char * str , qsizetype len )

[constexpr] QChar QAnyStringView:: back () const

[constexpr, since 6.5] void QAnyStringView:: chop ( qsizetype n )

[constexpr, since 6.5] QAnyStringView QAnyStringView:: chopped ( qsizetype n ) const

[static noexcept] int QAnyStringView:: compare ( QAnyStringView lhs , QAnyStringView rhs , Qt::CaseSensitivity cs = Qt::CaseSensitive)

[constexpr noexcept] const void *QAnyStringView:: data () const

[constexpr noexcept] bool QAnyStringView:: empty () const

[constexpr, since 6.5] QAnyStringView QAnyStringView:: first ( qsizetype n ) const

[static constexpr noexcept] template <typename Char, size_t Size, QAnyStringView::if_compatible_char<Char> = true> QAnyStringView QAnyStringView:: fromArray (const Char (&)[ Size ] string )

[constexpr] QChar QAnyStringView:: front () const

[constexpr noexcept] bool QAnyStringView:: isEmpty () const

[constexpr noexcept] bool QAnyStringView:: isNull () const

[constexpr, since 6.5] QAnyStringView QAnyStringView:: last ( qsizetype n ) const

[constexpr noexcept] qsizetype QAnyStringView:: length () const

[constexpr noexcept, since 6.8] qsizetype QAnyStringView:: max_size () const

[constexpr noexcept] qsizetype QAnyStringView:: size () const

[constexpr noexcept] qsizetype QAnyStringView:: size_bytes () const

[constexpr, since 6.8] QAnyStringView &QAnyStringView:: slice ( qsizetype pos , qsizetype n )

[constexpr, since 6.8] QAnyStringView &QAnyStringView:: slice ( qsizetype pos )

[constexpr, since 6.5] QAnyStringView QAnyStringView:: sliced ( qsizetype pos ) const

[constexpr, since 6.5] QAnyStringView QAnyStringView:: sliced ( qsizetype pos , qsizetype n ) const

QString QAnyStringView:: toString () const

[constexpr, since 6.5] void QAnyStringView:: truncate ( qsizetype n )

[constexpr] template <typename Visitor> decltype ( auto ) QAnyStringView:: visit ( Visitor && v ) const

相关非成员

[noexcept] bool operator!= (const QAnyStringView & lhs , const QAnyStringView & rhs )

[noexcept] bool operator< (const QAnyStringView & lhs , const QAnyStringView & rhs )

[noexcept] bool operator<= (const QAnyStringView & lhs , const QAnyStringView & rhs )

[noexcept] bool operator== (const QAnyStringView & lhs , const QAnyStringView & rhs )

[noexcept] bool operator> (const QAnyStringView & lhs , const QAnyStringView & rhs )

[noexcept] bool operator>= (const QAnyStringView & lhs , const QAnyStringView & rhs )

[since 6.7] QDebug operator<< ( QDebug d , QAnyStringView s )

内容

`[constexpr noexcept]` QAnyStringView:: QAnyStringView ()

`[constexpr noexcept]` template <typename Char, QAnyStringView::if_compatible_char<Char> = true> QAnyStringView:: QAnyStringView (const Char & ch )

`[constexpr noexcept]` template <typename Char, size_t N> QAnyStringView:: QAnyStringView (const Char (&)[ N ] string )

`[constexpr noexcept]` template <typename Char> QAnyStringView:: QAnyStringView (const Char * str )

`[constexpr noexcept]` template <typename Container, QAnyStringView::if_compatible_container<Container> = true> QAnyStringView:: QAnyStringView (const 容器 & str )

`[noexcept]` QAnyStringView:: QAnyStringView (const QByteArray & str )

`[noexcept]` QAnyStringView:: QAnyStringView (const QString & str )

`[constexpr noexcept]` QAnyStringView:: QAnyStringView ( std::nullptr_t )

`[constexpr]` template <typename Char, QAnyStringView::if_compatible_char<Char> = true> QAnyStringView:: QAnyStringView (const Char * first , const Char * last )

`[constexpr]` template <typename Char, QAnyStringView::if_compatible_char<Char> = true> QAnyStringView:: QAnyStringView (const Char * str , qsizetype len )

`[constexpr]` QChar QAnyStringView:: back () const

`[constexpr, since 6.5]` void QAnyStringView:: chop ( qsizetype n )

`[constexpr, since 6.5]` QAnyStringView QAnyStringView:: chopped ( qsizetype n ) const

`[static noexcept]` int QAnyStringView:: compare ( QAnyStringView lhs , QAnyStringView rhs , Qt::CaseSensitivity cs = Qt::CaseSensitive)

`[constexpr noexcept]` const void *QAnyStringView:: data () const

`[constexpr noexcept]` bool QAnyStringView:: empty () const

`[constexpr, since 6.5]` QAnyStringView QAnyStringView:: first ( qsizetype n ) const

`[static constexpr noexcept]` template <typename Char, size_t Size, QAnyStringView::if_compatible_char<Char> = true> QAnyStringView QAnyStringView:: fromArray (const Char (&)[ Size ] string )

`[constexpr]` QChar QAnyStringView:: front () const

`[constexpr noexcept]` bool QAnyStringView:: isEmpty () const

`[constexpr noexcept]` bool QAnyStringView:: isNull () const

`[constexpr, since 6.5]` QAnyStringView QAnyStringView:: last ( qsizetype n ) const

`[constexpr noexcept]` qsizetype QAnyStringView:: length () const

`[constexpr noexcept, since 6.8]` qsizetype QAnyStringView:: max_size () const

`[constexpr noexcept]` qsizetype QAnyStringView:: size () const

`[constexpr noexcept]` qsizetype QAnyStringView:: size_bytes () const

`[constexpr, since 6.8]` QAnyStringView &QAnyStringView:: slice ( qsizetype pos , qsizetype n )

`[constexpr, since 6.8]` QAnyStringView &QAnyStringView:: slice ( qsizetype pos )

`[constexpr, since 6.5]` QAnyStringView QAnyStringView:: sliced ( qsizetype pos ) const

`[constexpr, since 6.5]` QAnyStringView QAnyStringView:: sliced ( qsizetype pos , qsizetype n ) const

`[constexpr, since 6.5]` void QAnyStringView:: truncate ( qsizetype n )

`[constexpr]` template <typename Visitor> decltype ( auto ) QAnyStringView:: visit ( Visitor && v ) const

`[noexcept]` bool operator!= (const QAnyStringView & lhs , const QAnyStringView & rhs )

`[noexcept]` bool operator< (const QAnyStringView & lhs , const QAnyStringView & rhs )

`[noexcept]` bool operator<= (const QAnyStringView & lhs , const QAnyStringView & rhs )

`[noexcept]` bool operator== (const QAnyStringView & lhs , const QAnyStringView & rhs )

`[noexcept]` bool operator> (const QAnyStringView & lhs , const QAnyStringView & rhs )

`[noexcept]` bool operator>= (const QAnyStringView & lhs , const QAnyStringView & rhs )

`[since 6.7]` QDebug operator<< ( QDebug d , QAnyStringView s )