String

字符串类

一个简单的可自定义实现的字符串类实现，该类别模仿std :: String的功能，包括迭代器。

使用语句

 using size_type = size_t; // size_type for positions of char in cstring
using const_pointer = const_iterator;
using pointer = iterator;
using const_reverse_pointer = const_reverse_iterator;
using reverse_pointer = reverse_iterator;

构造函数

 String(); // default constructor  
String(const String &); // copy constructor  
String(const String& other, size_type pos, size_t len = npos); // substring constructor  
String(String &&); // move constructor  
String(const char *); // from c-string  
String(const char* s, size_t n); // from buffer  
String(size_t n, char c);// fill constructor  
String(const const_iterator first, const const_iterator second); // range constructor 

平等操作员

 String & operator= (const String &); // copy assignment   
String & operator = (String &&); // move assignment

驱动器

 ~String(); 

迭代器

将迭代器/const_iter返回到第一个字符

 iterator begin(); 
const_iterator begin() const;   

返回迭代器/const_iterator指向字符串的过去字符

 iterator end();  
const_iterator end() const; 

返回指向字符串的第一个字符 /过去字符的const_iterator

 const_iterator cbegin() const;  
const_iterator cend() const; 

返回reverse_iterator/const_reverse_iterator到最后一个字符

 reverse_iterator rbegin();  
const_reverse_iterator rbegin() const; 

返回reverse_iterator/const_reverse_iterator指向字符串的过去末端字符

 reverse_iterator rend(); 
const_reverse_iterator rend() const; 

返回const_reverse_iterator指向字符串的最后一个字符 /反向过去字符

 const_reverse_iterator crbegin() const; 
const_reverse_iterator crend() const; 

元素访问

获取字符串的字符

 const char & operator [] (size_type) const;
char & operator [] (size_type);

在字符串中获取字符

 const char & at(size_type) const;
char & at(size_type);

访问第一个字符

 const char & front() const;
char & front();

访问最后一个字符

 const char & back() const;
char & back();

修饰符

附加到字符串

 String & operator += (const String &); // string (1)
String & operator += (const char *); // c - string (2)
String & operator += (char); // char (3)

附加到字符串

 String& append(const String& str); // string (1)
String& append(const String& str, size_type subpos, size_t sublen = npos); // substring (2)
String& append(const char* s); // c - string (3)
String& append(const char* s, size_t n); // buffer(4)
String& append(size_type n, char c); // fill(5)
String& append(const const_iterator first, const const_iterator second); // range(6)

将字符附加到字符串

 String & push_back(char);

插入字符串

 String& insert(size_type pos, const String& other); 	// string(1)
String& insert(size_type pos, const String& other, size_type subpos, size_t sublen = npos); 	// substring(2)
String& insert(size_type pos, const char* other); // c - string(3)
String& insert(size_type pos, const char* s, size_t n); 	// buffer(4)
String& insert(size_type pos, size_t n, char c); 	// fill(5)
void insert(iterator p, size_t n, char c); 	// fill(6)
iterator insert(iterator p, char c); 	// single character(7)
void insert(iterator p, const const_iterator first, const const_iterator last); 	// range(8)  

从字符串中删除字符

 String& erase(size_type pos = 0, size_t len = npos); 	// sequence(1)
iterator erase(const_iterator p); // character(2)
iterator erase(const_iterator first, const_iterator last); // range(3)  

更换字符串的部分

 String& replace(size_type pos, size_t len, const String& other); // string(1)
String& replace(const_iterator i1, const_iterator i2, const String& other); // string(2)
String& replace(size_type pos, size_t len, const String& other, size_type subpos, size_t sublen = npos); // substring(3)
String& replace(size_type pos, size_t len, const char* s); // c - string(4)
String& replace(const_iterator i1, const_iterator i2, const char* other);  // c - string(5)
String& replace(size_type pos, size_t len, const char* other, size_t n); // buffer(6)
String& replace(const_iterator i1, const_iterator i2, const char* other, size_t n); // buffer(7)	
String& replace(size_type pos, size_t len, size_t n, char c); // fill(8)
String& replace(const_iterator i1, const_iterator i2, size_type n, char c); // fill(9)
String& replace(const_iterator i1, const_iterator i2, const_iterator first, const_iterator second); // range(10)  

交换字符串值

 void swap(String &);

删除最后一个字符

 String & pop_back();  

字符串操作

获取c字符串等效

 const char * c_str() const;

从字符串复制字符序列

 size_t copy(char* s, size_t len, size_type pos = 0) const;

在字符串中查找内容

 size_type find(const String& other, size_type pos = 0) const; //string(1)
size_type find(const char* s, size_type pos = 0) const; // c - string(2)
size_type find(const char* s, size_type pos, size_type n) const; // buffer(3)
size_type find(char c, size_type pos = 0) const; // character(4)

在字符串中查找内容的最后出现

 size_type rfind(const String& other, size_type pos = npos) const; // string(1)
size_type rfind(const char* s, size_type pos = npos) const; // c - string(2)
size_type rfind(const char* s, size_type pos, size_t n) const; // buffer(3)
size_type rfind(char c, size_type pos = npos) const; // character(4)

在字符串中找到字符

 size_type find_first_of(const String& other, size_type pos = 0) const; // string(1)
size_type find_first_of(const char* other, size_type pos = 0) const; 	// c - string(2)
size_type find_first_of(const char* other, size_type pos, size_t n) const; 	// buffer(3)
size_type find_first_of(char c, size_type pos = 0) const; // character(4)

从末端找到字符串中的字符

 size_type find_last_of(const String& other, size_type pos = String::npos) const; // string(1)
size_type find_last_of(const char* other, size_type pos = String::npos) const; // c - string(2)
size_type find_last_of(const char* other, size_type pos, size_t n) const; // buffer(3)
size_type find_last_of(char c, size_type pos = String::npos) const; 	// character(4)

在字符串中找到缺乏字符

 size_type find_first_not_of(const String& other, size_type pos = 0) const; // string(1)
size_type find_first_not_of(const char* other, size_type pos = 0) const; 	// c - string(2)
size_type find_first_not_of(const char* other, size_type pos, size_t n) const; // buffer(3)
size_type find_first_not_of(char c, size_type pos = 0) const; // character(4)

从末尾找到字符串中的非匹配字符

 size_type find_last_not_of(const String& other, size_type pos = String::npos) const; // string(1)
size_type find_last_not_of(const char* other, size_type pos = String::npos) const; // c - string(2)
size_type find_last_not_of(const char* other, size_type pos, size_t n) const; // buffer(3)
size_type find_last_not_of(char c, size_type pos = String::npos) const; // character(4)

生成子字符串

 String substr(size_type pos = 0, size_t len = npos) const;

容量

返回字符串长度

 size_t length() const;
size_t size() const;

返回字符串的最大尺寸

 size_t max_size() const;

调整字符串

 void resize(size_t n);
void resize(size_type n, char c);

分配存储的返回大小

 size_t capacity() const;

要求更改容量

 void reserve(size_t n = 0);

清除字符串

 void clear();

返回true是字符串是空的

 bool empty() const;

收缩适合

 void shrink_to_fit();

会员常数

 static const size_t npos = -1; // Maximum value for size_t

非会员功能超载

比较

 // Size is compared and if equal then comapred lexicographically
friend bool operator == (const String &, const String &);   
friend bool operator != (const String &, const String &);   
friend bool operator < (const String &, const String &);  
friend bool operator > (const String &, const String &);  
friend bool operator <= (const String &, const String &);  
friend bool operator >= (const String &, const String &);

交换两个字符串的值

 void swap(String& x, String& y);

返回串联字符串

 String operator+ (const String& lhs, const String& rhs);
String operator+ (const String& lhs, const char*   rhs);
String operator+ (const char*   lhs, const String& rhs);
String operator+ (const String& lhs, char rhs);
String operator+ (char lhs, const String& rhs);

将字符串插入流中

 std::ostream& operator<< (std::ostream& os, const _JD String& str);

从流中提取字符串

 std::istream& operator>> (std::istream& is, _JD String& str);

将线从流到字符串中获取

 std::istream& getline(std::istream& is, _JD String& str, char delim);
std::istream& getline(std::istream& is, _JD String& str);