begin gets the iterator that points to the beginning of the string
end gets the iterator that points to the end of the string
Rbegin Gets the iterator that points to the beginning of the reverse string
Rend gets the iterator that points to the end of the reverse string
size to get string sizes
Length () is the same function as the size function
max_size The maximum possible size of a string
capacity The possible size of a string without reallocating memory
empty to determine if null
operator[] takes the first few elements, the equivalent of an array
C_str get C-style const char* string
data gets the string content address
operator= assignment operator
Reserve Space
Swap swap function
Insert Insertion Character
Append Append characters
push_back Append characters
Erase Deleting a string
clear clears all contents of the character container
Resize Reallocate Space
assign is the same as the assignment operator
Replace Replace
copy string to space
Find lookup, returns the 0-based index number
RFind Reverse Lookup
Find_first_of finds any character in the containing substring and returns to the first position
find_first_not_of Find does not contain any characters in a substring, return to the first position
Find_last_of finds any character in the containing substring, returning to the last position
find_last_not_of Find does not contain any characters in the substring, return to the last position
substr (n1,len) gets a substring of length Len starting with a string from N1
Compare strings (all relational operators are supported)
Compare comparing Strings
operator+ String Links
operator+= + = operator
operator== judge whether equal
operator!= judgment is not equal to
operator< Judging whether it is less than
operator>> reading a string from the input stream
operator<< String writes to the output stream
Getline reads a line from the input stream
C + + string
