Qt::Literals::StringLiterals Namespace

namespace Qt :: Literals ::StringLiterals

The StringLiterals namespace declares literal operators for Qt string types. 更多...

頭：	#include <QString>
CMake:	find_package(Qt6 REQUIRED COMPONENTS Core) target_link_libraries(mytarget PRIVATE Qt6::Core)
qmake:	QT += core

函數

(從 6.4 起) QLatin1Char	operator""_L1 (char ch )
(從 6.4 起) QLatin1StringView	operator""_L1 (const char * str , size_t size )
(從 6.4 起) QByteArray	operator""_ba (const char * str , size_t size )
(從 6.4 起) QString	operator""_s (const char16_t * str , size_t size )

詳細描述

內聯 Qt::Literals::StringLiterals 名稱空間聲明用於 Qt 字符串類型的文字操作符。因為兩者 Literals and StringLiterals 名稱空間是以內聯方式聲明的，所以，來自此名稱空間的符號可以通過在代碼中添加下列之一訪問：

// Makes visible only the literal operators declared in StringLiterals
using namespace Qt::StringLiterals;
// same, but needlessly verbose:
using namespace Qt::Literals::StringLiterals;
// Makes visible literal operators declared in all inline namespaces
// inside Literals
using namespace Qt::Literals;
// Makes visible all symbols (including all literal operators) declared
// in the Qt namespace
using namespace Qt;
					

後者不受鼓勵，因為它不允許拾取想要的字麵操作符，以防 Qt 在不同命名空間添加衝突操作符按 Qt::Literals .

函數文檔編製

[constexpr noexcept, since 6.4] QLatin1Char operator""_L1 ( char ch )

文字運算符創建的 QLatin1Char out of ch .

以下代碼創建 QLatin1Char :

using namespace Qt::StringLiterals;
auto ch = 'a'_L1;
					

該函數在 Qt 6.4 引入。

另請參閱 Qt::Literals::StringLiterals .

[constexpr noexcept, since 6.4] QLatin1StringView operator""_L1 (const char * str , size_t size )

文字運算符創建的 QLatin1StringView out of the first size characters in the char string literal str .

以下代碼創建 QLatin1StringView :

using namespace Qt::StringLiterals;
auto str = "hello"_L1;
					

該函數在 Qt 6.4 引入。

另請參閱 Qt::Literals::StringLiterals .

[noexcept, since 6.4] QByteArray operator""_ba (const char * str , size_t size )

文字運算符創建的 QByteArray out of the first size characters in the char string literal str .

The QByteArray is created at compile time, and the generated string data is stored in the read-only segment of the compiled object file. Duplicate literals may share the same read-only memory. This functionality is interchangeable with QByteArrayLiteral , but saves typing when many string literals are present in the code.

以下代碼創建 QByteArray :

using namespace Qt::StringLiterals;
auto str = "hello"_ba;
					

該函數在 Qt 6.4 引入。

另請參閱 Qt::Literals::StringLiterals .

[noexcept, since 6.4] QString operator""_s (const char16_t * str , size_t size )

文字運算符創建的 QString out of the first size characters in the char16_t string literal str .

The QString is created at compile time, and the generated string data is stored in the read-only segment of the compiled object file. Duplicate literals may share the same read-only memory. This functionality is interchangeable with QStringLiteral , but saves typing when many string literals are present in the code.

以下代碼創建 QString :

using namespace Qt::StringLiterals;
auto str = u"hello"_s;
					

該函數在 Qt 6.4 引入。

另請參閱 Qt::Literals::StringLiterals .

內容

1. 函數

2. 詳細描述