std::basic_string
Defined in header <string> | | |
|---|---|---|
template< class CharT, class Traits = std::char_traits<CharT>, class Allocator = std::allocator<CharT> > class basic_string; | (1) | |
namespace pmr { template <class CharT, class Traits = std::char_traits<CharT>> using basic_string = std::basic_string< CharT, Traits, std::polymorphic_allocator<CharT>> } | (2) | (since C++17) |
类模板basic_string存储和操作char-像物体。类既不依赖于字符类型，也不依赖于对该类型的操作的性质。操作的定义通过Traits模板参数-一个专门化的std::char_traits或者是一个兼容的特征类。Traits::char_type和CharT必须命名相同类型；否则行为未定义。
The elements of a basic_string are stored contiguously, that is, for a basic_string s, &*(s.begin() + n) == &*s.begin() + n for any n in [0, s.size()), or, equivalently, a pointer to s0 can be passed to functions that expect a pointer to the first element of a CharT[] array. | (since C++11) |
|---|
std::basic_string满足…的要求AllocatorAwareContainer，，，SequenceContainer和ContiguousContainer%28自C++17%29。
提供了几种常见字符类型的类型：
在标头中定义<string>
*。
类型定义
STD：：String STD：：basic[医]弦<char>
std：：wstring std：：basic[医]字符串<wchar[医]T>
STD：：u16string%28C++11%29 std：：basic[医]字符串<char16[医]T>
STD：：u32string%28C++11%29 std：：basic[医]字符串<char32[医]T>
std：：pmr：：string%28C++17%29 std：：pmr：：basic[医]弦<char>
std：：pmr：：wstring%28C++17%29 std：：pmr：：basic[医]字符串<wchar[医]T>
std：：pmr：：u16string%28C++17%29 std：：pmr：：basic[医]字符串<char16[医]T>
std：：pmr：：u32string%28C++17%29 std：：pmr：：basic[医]字符串<char32[医]T>
模板参数
CharT | - | character type |
|---|---|---|
Traits | - | traits class specifying the operations on the character type |
Allocator | - | Allocator type used to allocate internal storage |
成员类型
Member type | Definition | ||||
|---|---|---|---|---|---|
traits_type | Traits | ||||
value_type | CharT | ||||
allocator_type | Allocator | ||||
size_type | Allocator::size_type (until C++11) std::allocator_traits<Allocator>::size_type (since C++11) | Allocator::size_type | (until C++11) | std::allocator_traits<Allocator>::size_type | (since C++11) |
Allocator::size_type | (until C++11) | ||||
std::allocator_traits<Allocator>::size_type | (since C++11) | ||||
difference_type | Allocator::difference_type (until C++11) std::allocator_traits<Allocator>::difference_type (since C++11) | Allocator::difference_type | (until C++11) | std::allocator_traits<Allocator>::difference_type | (since C++11) |
Allocator::difference_type | (until C++11) | ||||
std::allocator_traits<Allocator>::difference_type | (since C++11) | ||||
reference | Allocator::reference (until C++11) value_type& (since C++11) | Allocator::reference | (until C++11) | value_type& | (since C++11) |
Allocator::reference | (until C++11) | ||||
value_type& | (since C++11) | ||||
const_reference | Allocator::const_reference (until C++11) const value_type& (since C++11) | Allocator::const_reference | (until C++11) | const value_type& | (since C++11) |
Allocator::const_reference | (until C++11) | ||||
const value_type& | (since C++11) | ||||
pointer | Allocator::pointer (until C++11) std::allocator_traits<Allocator>::pointer (since C++11) | Allocator::pointer | (until C++11) | std::allocator_traits<Allocator>::pointer | (since C++11) |
Allocator::pointer | (until C++11) | ||||
std::allocator_traits<Allocator>::pointer | (since C++11) | ||||
const_pointer | Allocator::const_pointer (until C++11) std::allocator_traits<Allocator>::const_pointer (since C++11) | Allocator::const_pointer | (until C++11) | std::allocator_traits<Allocator>::const_pointer | (since C++11) |
Allocator::const_pointer | (until C++11) | ||||
std::allocator_traits<Allocator>::const_pointer | (since C++11) | ||||
iterator | RandomAccessIterator | ||||
const_iterator | Constant random access iterator | ||||
reverse_iterator | std::reverse_iterator<iterator> | ||||
const_reverse_iterator | std::reverse_iterator<const_iterator> |
成员函数
(constructor) | constructs a basic_string (public member function) |
|---|---|
(destructor) | destroys the string, deallocating internal storage if used (public member function) |
operator= | assigns values to the string (public member function) |
assign | assign characters to a string (public member function) |
get_allocator | returns the associated allocator (public member function) |
元素存取
访问指定字符时，检查%28公共成员函数%29
操作者。[访问指定字符%28公共成员函数%29
前端%28C++11%29访问第一个字符%28公共成员函数%29
Back%28C++11%29访问最后一个字符%28公共成员函数%29
数据返回指向字符串%28公共成员函数%29的第一个字符的指针。
丙[医]Str返回字符串%28公共成员函数%29的不可修改的标准C字符数组版本。
运算符BASIC[医]弦[医]视图%28C++17%29返回不可修改的字符串。[医]查看整个字符串%28公共成员函数%29
迭代器
初学者%28C++11%29返回一个迭代器到开头%28公共成员函数%29
End Cend%28C++11%29将迭代器返回到末尾%28公共成员函数%29
rback crback%28C++11%29将反向迭代器返回到起始%28公共成员函数%29
Rendcrend%28C++11%29将反向迭代器返回到结束%28公共成员函数%29
容量
空检查字符串是否为空%28公共成员函数%29
Szelength返回字符数%28公共成员函数%29
马克斯[医]Size返回最大字符数%28公共成员函数%29
储备储备储备%28公众会员功能%29
容量返回当前分配的存储空间%28公共成员函数%29中可以保存的字符数。
收缩[医]到[医]FIT%28C++11%29通过释放未使用内存%28公共成员函数%29来减少内存使用
操作
清除内容%28公共成员功能%29
插入字符%28公共成员函数%29
删除字符%28公共成员函数%29
推[医]向末尾%28公共成员函数%29追加一个字符
波普[医]后退%28C++11%29移除最后一个字符%28公共成员函数%29
将字符追加到末尾%28公共成员函数%29
运算符+=将字符追加到末尾%28公共成员函数%29
比较两个字符串%28公共成员函数%29
替换字符串%28公共成员函数%29的指定部分
子字符串%28公共成员函数%29
复制字符%28公共成员函数%29
调整大小更改存储的字符数%28公共成员函数%29
交换交换内容%28公共成员函数%29
搜索
在字符串%28公共成员函数%29中查找字符
查找子字符串%28公共成员函数%29的最后一次出现
找出[医]第一[医]第一次出现字符%28公共成员函数%29
找出[医]第一[医]不[医]查找第一次缺少字符%28公共成员函数%29
找出[医]最后[医]查找最后出现的字符%28公共成员函数%29
找出[医]最后[医]不[医]%28公共成员函数%29
常数
非营利组织静态特殊价值。确切意义取决于上下文%28公共静态成员常量%29
非会员职能
operator+ | concatenates two strings or a string and a char (function template) |
|---|---|
operator==operator!=operator<operator>operator<=operator>= | lexicographically compares two strings (function template) |
std::swap(std::basic_string) | specializes the std::swap algorithm (function template) |
输入/输出
运算符<<operator>>对字符串%28函数模板%29执行流输入和输出
将I/O流中的数据读取到字符串%28函数模板%29中
数值转换
斯托斯特洛斯托尔%28C++11%29%28C++11%29%28C+11%29将字符串转换为有符号整数%28函数%29
stoulstoull%28C++11%29%28C++11%29将字符串转换为无符号整数%28函数%29
stofstodstold%28C++11%29%28C++11%29%28C+11%29将字符串转换为浮点值%28函数%29
到[医]字符串%28C++11%29将整数或浮点值转换为字符串%28函数%29
到[医]wstring%28C++11%29将整数或浮点值转换为wstring%28函数%29。
文字
定义在内联命名空间std：：alals：：string中[医]文字
*。
运算符“s%28C++14%29将字符数组文字转换为Basic[医]字符串%28功能%29
帮助者类
std::hash<std::string>std::hash<std::u16string>std::hash<std::u32string>std::hash<std::wstring> (C++11)(C++11)(C++11)(C++11) | hash support for strings (class template specialization) |
|---|
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