Modifying Operations

C++ gives us a variety of tools to modify and manipulate strings.

Strings have many operations that can modify them. str.assign assigns a new string to the string str. With str.swap we can swap two strings. To remove a character from a string use str.pop_back or str.erase. On the contrary, str.clear or str.erase deletes the whole string. To append new characters to a string, use +=, std.append or str.push_back. We can use str.insert to insert new characters or str.replace to replace them.

Methods Description
str= str2 Assigns str2 to str.
str.assign(...) Assigns a new string to str.
str.swap(str2) Swaps str and str2.
str.pop_back() Removes the last character from str.
str.erase(...) Removes characters from str.
str.clear() Clears the str.
str.append(...) Appends characters to str.
str.push_back(s) Appends the character s to str.
str.insert(pos, ...) Inserts characters in str starting at pos.
str.replace(pos, len, ...) Replaces the len characters from str starting at pos

Methods for modifying a string

The operations have many overloaded versions. The methods str.assign, str.append, str.insert, and str.replace are very similar. All four can not only be invoked with C++ strings and substrings but also characters, C strings, C string arrays, ranges, and initializer lists. str.erase can not only erase a single character and whole ranges, but also many characters starting at a given position.

The following code snippet shows many of the variations. For the sake of simplicity, only the effects of the strings modifications are displayed:

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