Simple formatting question..

[Mr Moe]

New here, thought I'd start off with something easy.

Ok I have this function that converts an (int) into a 4 octect IP address, storing each octet of the IP into an array. To output this as a normal IP address, I have to add the dots between each number. The code goes as thus ( all you really need to note is the cout statement at the bottom )-

    int i = 0;
    int n = 24;
    IP octet[4];  //unsigned int

    for ( i = 0 ; i < 4 ; i++)
    {
        octet[i] = ( ( address >> n ) & 255 );
        n -=8;
    }

cout << octet[0] << "." << octet[1] << "." << octet[2] << "." << octet[3];

So the output looks something like 192.24.159.1, just as an example.

My question is, I am going to output this in a list with multiple lines, and will be outputting items after this on the same line. So I need to set width to 16 and align this IP to the left, then output the rest of the line uniformly. However, I am unsure how to do this, since the setw() function only grabs the next item on the output stream ( in this case, octet[0] ), and the rest will be pushed a dozen or so spaces over. I need to find a way to make it so this entire bit of code ( the cout statement of this function, basically ) is aligned to the left of a 16-space spot. Not sure if this would involve changing my output, but I'm up for any suggestions.

Sorry if this description is not adequate, I can sure repost if necessary. Thanks for any help.

[major_small]

is using tabs after your last octet acceptable? depending on your environment, one tab may be enough to do what you want...

in other words, have you tried

cout << octet[0] << "." << octet[1] << "." << octet[2] << "." << octet[3]<<'\t';

if not, what about blank spaces? by that I mean can you output this:

192.168.  0. 12

if so, try using width()

[Mr Moe]

Actually the tab will work perfectly. Thanks! I knew it had to be something simple that just wasn't coming to mind.

[Scribbler]

Seems like a perfect opportunity to use a class. I don't know your specific implementation but you could probably adapt it or come up with something similar (could probably be improved upon as well ie..another constructor to accept an array of 4 ints, I whipped it up real quick).

OctetAddress.h

#ifndef OCTETADDRESS_H
#define OCTETADDRESS_H

#include <iostream>
#include <string>
#include <sstream>

using std::cout;
using std::ostringstream;
using std::string;

class OctetAddress {
	
	private:
		string octetString;
		int octetField[4];
		void setOctetString();
	
	public:
		OctetAddress( int = 0, int = 0, int = 0, int = 0 );
		void setOctet( int = 0, int = 0, int = 0, int = 0 );
		string getOctetString() const;

};

OctetAddress::OctetAddress( int a, int b, int c, int d )
{
	setOctet( a, b, c, d );
}

void OctetAddress::setOctet( int a, int b, int c, int d )
{
	octetField[0] = ( a > 255 || a < 0 ? 0 : a );	//
	octetField[1] = ( b > 255 || b < 0 ? 0 : b );	// Ensure values
	octetField[2] = ( c > 255 || c < 0 ? 0 : c );	// are in range
	octetField[3] = ( d > 255 || d < 0 ? 0 : d );	//
	setOctetString();
}

void OctetAddress::setOctetString()
{
	ostringstream buildString;
	buildString << octetField[0] << "." << octetField[1] << "." << octetField[2] << "." << octetField[3];
	octetString = buildString.str();
}

string OctetAddress::getOctetString() const
{
	return octetString;
}

#endif

And a simple example how it's easy to provide organized output.

sampleUse.cpp

#include <iostream>
#include <iomanip>
#include "OctetAddress.h"

using std::cout;
using std::cin;
using std::setw;
using std::left;
using std::endl;

int main()
{
	
	int octet[4];
	
	cout << "Enter 4 ints:" << endl;
	for (int n = 0 ; n < 4 ; n++ )
		cin >> octet[n];
	
	OctetAddress ipAddress1( octet[0], octet[1], octet[2], octet[3] );
	OctetAddress ipAddress2;
	
	
	cout << setw(16) << left << ipAddress1.getOctetString() << "random text" << endl;
	cout << setw(16) << left << ipAddress2.getOctetString() << "random text" << endl;
	
	ipAddress2.setOctet( 192, 168, 0, 1 );
	cout << setw(16) << left << ipAddress2.getOctetString() << "random text" << endl;
	
	return 0;
}

[7stud]

If you want more control over the output than a tab, you could also do it like this:

int octet[] = {192, 24, 159, 1};

//Create a variable that allows you use the << operator to append non-string types:
stringstream combined_string; 
combined_string << octet[0] << "." << octet[1] << "." << octet[2] << "." << octet[3];

//Use the str() function to get the contents of the variable:
cout << combined_string.str()<< "xxxx" <<endl;  

//Use setw() and left to format the output for the variable, then return to default settings:
cout<<setw(16)<<left<<combined_string.str()<<setw(0)<<right<<"xxxx"<<" yyyy"<<endl;

You need to include <sstream> and <iomanip>.

[Mr Moe]

Thanks a bunch guys, I'll give some of that a shot. I really appreciate the help