📅 最后修改于: 2020-10-16 07:13:12 🧑 作者: Mango
在C++中， 字符串是std :: 字符串类的对象，它表示字符序列。我们可以对字符串执行许多操作，例如连接，比较，转换等。
让我们看一下C++ 字符串的简单示例。
#include
using namespace std;
int main( ) {
string s1 = "Hello";
char ch[] = { 'C', '+', '+'};
string s2 = string(ch);
cout< 输出：
Hello
C++
让我们看一下使用strcmp()函数进行字符串比较的简单示例。
#include
#include
using namespace std;
int main ()
{
char key[] = "mango";
char buffer[50];
do {
cout<<"What is my favourite fruit? ";
cin>>buffer;
} while (strcmp (key,buffer) != 0);
cout<<"Answer is correct!!"< 输出：
What is my favourite fruit? apple
What is my favourite fruit? banana
What is my favourite fruit? mango
Answer is correct!!
让我们看一下使用strcat()函数进行字符串连接的简单示例。
#include
#include
using namespace std;
int main()
{
char key[25], buffer[25];
cout << "Enter the key string: ";
cin.getline(key, 25);
cout << "Enter the buffer string: ";
cin.getline(buffer, 25);
strcat(key, buffer);
cout << "Key = " << key << endl;
cout << "Buffer = " << buffer< 输出：
Enter the key string: Welcome to
Enter the buffer string: C++ Programming.
Key = Welcome to C++ Programming.
Buffer = C++ Programming.
让我们看一下使用strcpy()函数复制字符串的简单示例。
#include
#include
using namespace std;
int main()
{
char key[25], buffer[25];
cout << "Enter the key string: ";
cin.getline(key, 25);
strcpy(buffer, key);
cout << "Key = "<< key << endl;
cout << "Buffer = "<< buffer< 输出：
Enter the key string: C++ Tutorial
Key = C++ Tutorial
Buffer = C++ Tutorial
让我们看一下使用strlen()函数查找字符串长度的简单示例。
#include
#include
using namespace std;
int main()
{
char ary[] = "Welcome to C++ Programming";
cout << "Length of String = " << strlen(ary)< 输出：
Length of String = 26
| Function | Description |
|---|---|
| int compare(const string& str) | It is used to compare two string objects. |
| int length() | It is used to find the length of the string. |
| void swap(string& str) | It is used to swap the values of two string objects. |
| string substr(int pos,int n) | It creates a new string object of n characters. |
| int size() | It returns the length of the string in terms of bytes. |
| void resize(int n) | It is used to resize the length of the string up to n characters. |
| string& replace(int pos,int len,string& str) | It replaces portion of the string that begins at character position pos and spans len characters. |
| string& append(const string& str) | It adds new characters at the end of another string object. |
| char& at(int pos) | It is used to access an individual character at specified position pos. |
| int find(string& str,int pos,int n) | It is used to find the string specified in the parameter. |
| int find_first_of(string& str,int pos,int n) | It is used to find the first occurrence of the specified sequence. |
| int find_first_not_of(string& str,int pos,int n ) | It is used to search the string for the first character that does not match with any of the characters specified in the string. |
| int find_last_of(string& str,int pos,int n) | It is used to search the string for the last character of specified sequence. |
| int find_last_not_of(string& str,int pos) | It searches for the last character that does not match with the specified sequence. |
| string& insert() | It inserts a new character before the character indicated by the position pos. |
| int max_size() | It finds the maximum length of the string. |
| void push_back(char ch) | It adds a new character ch at the end of the string. |
| void pop_back() | It removes a last character of the string. |
| string& assign() | It assigns new value to the string. |
| int copy(string& str) | It copies the contents of string into another. |
| char& back() | It returns the reference of last character. |
| Iterator begin() | It returns the reference of first character. |
| int capacity() | It returns the allocated space for the string. |
| const_iterator cbegin() | It points to the first element of the string. |
| const_iterator cend() | It points to the last element of the string. |
| void clear() | It removes all the elements from the string. |
| const_reverse_iterator crbegin() | It points to the last character of the string. |
| const_char* data() | It copies the characters of string into an array. |
| bool empty() | It checks whether the string is empty or not. |
| string& erase() | It removes the characters as specified. |
| char& front() | It returns a reference of the first character. |
| string& operator+=() | It appends a new character at the end of the string. |
| string& operator=() | It assigns a new value to the string. |
| char operator[](pos) | It retrieves a character at specified position pos. |
| int rfind() | It searches for the last occurrence of the string. |
| iterator end() | It references the last character of the string. |
| reverse_iterator rend() | It points to the first character of the string. |
| void shrink_to_fit() | It reduces the capacity and makes it equal to the size of the string. |
| char* c_str() | It returns pointer to an array that contains null terminated sequence of characters. |
| const_reverse_iterator crend() | It references the first character of the string. |
| reverse_iterator rbegin() | It reference the last character of the string. |
| void reserve(inr len) | It requests a change in capacity. |
| allocator_type get_allocator(); | It returns the allocated object associated with the string. |