basic_string::operator=

Assigns new character values to the contents of a string.

basic_string<CharType, Traits, Allocator>& operator=(
   value_type _Ch
);
basic_string<CharType, Traits, Allocator>& operator=(
   const value_type* _Ptr
);
basic_string<CharType, Traits, Allocator>& operator=(
   const basic_string<CharType, Traits, Allocator>& _Right
);
basic_string<CharType, Traits, Allocator>& operator=(
   const basic_string<CharType, Traits, Allocator>&& _Right
);

Parameters

• _Ch
  The character value to be assigned.

• _Ptr
  A pointer to the characters of the C-string to be assigned to the target string.

• _Right
  The source string whose characters are to be assigned to the target string.

Return Value

A reference to the string object that is being assigned new characters by the member function.

Remarks

The strings may be assigned new character values. The new value may be either a string and C-string or a single character. The operator= may be used if the new value can be described by a single parameter, otherwise the member function assign, which has multiple parameters, may be used to specify which part of the string is to be assigned to a target string.

Example

// basic_string_op_assign.cpp
// compile with: /EHsc
#include <string>
#include <iostream>

int main( ) 
{
   using namespace std;

   // The first member function assigning a
   // character of a certain value to a string
   string str1a ( "Hello " );
   str1a = '0';
   cout << "The string str1 assigned with the zero character is: " 
        << str1a << endl << endl;

   // The second member function assigning the
   // characters of a C-string to a string
   string  str1b;
   const char *cstr1b = "Out There";
   cout << "The C-string cstr1b is: " << cstr1b <<  "." << endl;
   str1b = cstr1b;
   cout << "Assigning the C-string cstr1a to string str1 gives: " 
        << str1b << "." << endl << endl;

   // The third member function assigning the characters
   // from one string to another string in two equivalent
   // ways, comparing the assign and operator =
   string str1c ( "Hello" ), str2c ( "Wide" ), str3c ( "World" );
   cout << "The original string str1 is: " << str1c << "." << endl;
   cout << "The string str2c is: " << str2c << "." << endl;
   str1c.assign ( str2c );
   cout << "The string str1 newly assigned with string str2c is: " 
        << str1c << "." << endl;
   cout << "The string str3c is: " << str3c << "." << endl;
   str1c = str3c;
   cout << "The string str1 reassigned with string str3c is: " 
        << str1c << "." << endl << endl;
}

The string str1 assigned with the zero character is: 0

The C-string cstr1b is: Out There.
Assigning the C-string cstr1a to string str1 gives: Out There.

The original string str1 is: Hello.
The string str2c is: Wide.
The string str1 newly assigned with string str2c is: Wide.
The string str3c is: World.
The string str1 reassigned with string str3c is: World.

Requirements

Header: <string>

Namespace: std

See Also

Reference

basic_string Class

Other Resources

basic_string Members

Change History

Date	History	Reason
June 2010	Added a new format for the operator.	Information enhancement.