STL之string

原文地址：http://www.cplusplus.com/reference/string/string/

string

字符串是表示字符序列的对象。
标准字符串类使用类似于标准容器字节的接口来提供对这些对象的支持，但是添加专门用于以单字节字符串操作的功能。

使用string类之前必须加上<string>头文件：#include<string>;

构造函数

default (1)

string();

copy (2)

string (const string& str);

substring (3)

string (const string& str, size_t pos, size_t len = npos);

from c-string (4)

string (const char* s);

from buffer (5)

string (const char* s, size_t n);

fill (6)

string (size_t n, char c);

range (7)

template <class InputIterator>  string  (InputIterator first, InputIterator last);

initializer list (8)

string (initializer_list<char> il);

move (9)

string (string&& str) noexcept;

 

成员函数

Member functions

(constructor)

Construct string object (public member function )构造函数

(destructor)

String destructor (public member function )析构函数

operator=

String assignment (public member function )重载=

Iterators:

begin

Return iterator to beginning (public member function )获得begin迭代器

end

Return iterator to end (public member function )获得end迭代器

rbegin

Return reverse iterator to reverse beginning (public member function )

rend

Return reverse iterator to reverse end (public member function )

cbegin 

Return const_iterator to beginning (public member function )获得const begin迭代器

cend 

Return const_iterator to end (public member function )获得const end迭代器

crbegin 

Return const_reverse_iterator to reverse beginning (public member function )

crend 

Return const_reverse_iterator to reverse end (public member function )

Capacity:

size

Return length of string (public member function )字符串长度

length

Return length of string (public member function )

max_size

Return maximum size of string (public member function )

resize

Resize string (public member function )

capacity

Return size of allocated storage (public member function )

reserve

Request a change in capacity (public member function )

clear

Clear string (public member function )清空String类

empty

Test if string is empty (public member function )判断是否为空

shrink_to_fit 

Shrink to fit (public member function )

Element access:

operator[]

Get character of string (public member function )重载下标

at

Get character in string (public member function )下标索引

back 

Access last character (public member function )返回最后一个字符的左值

front 

Access first character (public member function )返回第一个字符的左值

Modifiers:

operator+=

Append to string (public member function )

append

Append to string (public member function )

push_back

Append character to string (public member function )添加字符串到字符串末尾

assign

Assign content to string (public member function )为字符串分配一个新值，替换其当前内容

insert

Insert into string (public member function )在指示下标前插入字符

erase

Erase characters from string (public member function )删除字符串

replace

Replace portion of string (public member function )替代字符串

swap

Swap string values (public member function )交换string的值

pop_back 

Delete last character (public member function )删除最后一个字符

String operations:

c_str

Get C string equivalent (public member function )

data

Get string data (public member function )

get_allocator

Get allocator (public member function )

copy

Copy sequence of characters from string (public member function )

find

Find content in string (public member function )搜索

rfind

Find last occurrence of content in string (public member function )

find_first_of

Find character in string (public member function )

find_last_of

Find character in string from the end (public member function )

find_first_not_of

Find absence of character in string (public member function )

find_last_not_of

Find non-matching character in string from the end (public member function )

substr

Generate substring (public member function )获得字串

compare

Compare strings (public member function )比较

数值和String的相互转换(非string成员函数)

to_string(val)

返回数值val的string表示

stoi(s,p,b)

返回s的字串的int数值，b表示转换基数，默认为10，p用来保存s中第一个非数值字符的下标，默认为0

stol(s,p,b)

返回s的字串的long数值

stoul(s,p,b)

返回s的字串的unsigned long数值

stoll(s,p,b) 

stof(s,p)

返回s的字串的float数值

stod(s,p)

返回s的字串的double数值

stold(s,p)

返回s的字串的long double数值