// str3.cpp		By: Aiman Hanna -  ©1993-2006 Aiman Hanna
//
// This program illustrates more of the C++ string type. In specific, the program 
// illustrates how the two string types (the C-Style and the C++ string) can be mapped 
// to each others. 
//
// In general, mapping from a C-Style string to C++ string is straightforward. However,
// the reverse conversion is not implicitly supported. C++ string is actually an array
// of characters (not a variable pointer to a character); that is why const is enforced here.
// The program clearly explains what is meant by that. 
//
//		Key Points:	1) Standard C++ string type 
//				2) C-Style strings
// 				3) Conversions between C++ and C-Style strings 
//				4) The c_str() method



#include <string>
#include <iostream>


using namespace std;

int main()
{
	char *cs1 = "Converted from", *cs2 = " a C-Style string.";	// Two C-Style strings
	char* cs3 = ", ";			// A usual C-Style string
	char* cs4;

	string s1 = cs1;

	s1 += cs2;
	
	cout << "s1 is: " << s1 << endl;

	string s2 = "Hello", s3 = "there.", s4;	// s4 is an empty string
	
	if (s4.empty())
	{
		cout << "\ns4 is empty; will perform some string operations.\n";

		
		s4 = s2 + cs3 + s3;

		// The following will simply display s4
		cout << "\ns4 is: ";
		for (int i = 0; i < s4.size(); i++)
			cout << s4[i];
		
	}

	
	// Now try to convert from C++ string to a C-style string
	// The following line will not compile. Un-comment it out and try. why?
	// c_str() returns a pointer to a constant array in order to prevent the 
	// array from being manipulated. 

	// cs4 = s1.c_str();

	// As a result, the following is what we need to do

	const char* cs5 = s1.c_str();
	cout << "\n\ncs5 is: " << cs5 << endl;
	cout << "Well, it is actually converted from C++ string!\n";



	cout << endl;
	return 0;
}

/* The output
s1 is: Converted from a C-Style string.

s4 is empty; will perform some string operations.

s4 is: Hello, there.

cs5 is: Converted from a C-Style string.
Well, it is actually converted from C++ string!!

*/