int to string

epb · 10-26-2009, 02:33 AM

Hi,

I tried the following code to convert an int to a string:

Code:

int i = 5678;
string s;
stringstream out;
out << i;
s = out.str();

But it returns an empty string! If I print the "out" variable using

Code:

cout << out << endl;

It prints "0". What could possibly be wrong? I'm using Mac OS X 10.6.1 and gcc version 4.2.1.

**laserlight** · 10-26-2009, 05:06 AM

Try printing s instead of out and you will probably find that out.str() did not return an empty string.

joseCarlos · 10-26-2009, 05:39 AM

you can do lyke this

int val=2635;
char s[50];
cout<<itoa(val,s,10)<<endl;

is that you want?

JacobN · 10-26-2009, 06:07 AM

Quote:

Originally Posted by joseCarlos

you can do lyke this

int val=2635;
char s[50];
cout<<itoa(val,s,10)<<endl;

is that you want?

Except that's C and not defined in ANSI-C nor a part of C++?

epb · 10-26-2009, 06:55 AM

Quote:

Originally Posted by laserlight

Try printing s instead of out and you will probably find that out.str() did not return an empty string.

Sorry if I wasn't clear about this.. I have already tried printing out 's', and that revealed an empty string (which is why I concluded that the code returns an empty string).

Quote:

Originally Posted by joseCarlos

you can do lyke this

Code:

int val=2635;
char s[50];
cout<<itoa(val,s,10)<<endl;

is that you want?

No that is not what I want.. I want to convert the int directly to a C++ string (of the string class)

**laserlight** · 10-26-2009, 07:46 AM

Quote:

Originally Posted by epb

Sorry if I wasn't clear about this.. I have already tried printing out 's', and that revealed an empty string (which is why I concluded that the code returns an empty string).

Okay, so given this program:

Code:

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

int main()
{
    using namespace std;
    int i = 5678;
    string s;
    stringstream out;
    out << i;
    s = out.str();
    cout << s << endl;
}

Compile and run it. What output do you get?

epb · 10-26-2009, 08:10 AM

Quote:

Originally Posted by laserlight

Okay, so given this program:

Code:

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

int main()
{
    using namespace std;
    int i = 5678;
    string s;
    stringstream out;
    out << i;
    s = out.str();
    cout << s << endl;
}

Compile and run it. What output do you get?

I get no output. If I add

Code:

cout << out << endl;

after the assignment of 'i' to 'out' I get '0' as a single output.

RockyMarrone · 10-26-2009, 08:14 AM

Quote:

Originally Posted by epb

I get no output. If I add

Code:

cout << out << endl;

after the assignment of 'i' to 'out' I get '0' as a single output.

Check this out

Code:

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

int main()
{
  using namespace std;
  int i = 5678;
  string s;
  stringstream out;
  out << i;
  cout << out.str() << endl;
  s = out.str();
  cout << s << endl;
}

epb · 10-26-2009, 08:25 AM

Quote:

Originally Posted by RockyMarrone

Check this out

Code:

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

int main()
{
  using namespace std;
  int i = 5678;
  string s;
  stringstream out;
  out << i;
  cout << out.str() << endl;
  s = out.str();
  cout << s << endl;
}

This is also gives me an empty output

EDIT: The output is two empty lines, so I guess you can say that the output is not completely empty

RockyMarrone · 10-26-2009, 08:30 AM

Quote:

Originally Posted by epb

This is also gives me an empty output

EDIT: This gives me two empty lines, so I guess you can say that the output is not entirely empty

I don't know why you are not getting the output but see my shell here

and for your information i m on linux 2.6.29.4 and gcc 4.3.2

Quote:

[rocky@localhost test]$ ls
a.out test.cc
[rocky@localhost test]$ cat test.cc

Code:

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

int main()
{
  using namespace std;
  int i = 5678;
  string s;
  stringstream out;
  out << i;
  cout << out.str() << endl;
  s = out.str();
  cout << s << endl;
}

[rocky@localhost test]$ g++ test.cc
.[rocky@localhost test]$ ./a.out
5678
5678

JacobN · 10-26-2009, 08:32 AM

According to this thread:

Cocoabuilder - (Dmitry Markman) ostringstream problem with Xcode 3.2

Assuming you're using Xcode, try setting it to build as Release rather than Debug?

**laserlight** · 10-26-2009, 08:32 AM

Quote:

Originally Posted by epb

after the assignment of 'i' to 'out' I get '0' as a single output.

hmm... that should imply that the stringstream is in a failed state, which is strange.

epb · 10-26-2009, 08:34 AM

Quote:

Originally Posted by JacobN

According to this thread:

Cocoabuilder - (Dmitry Markman) ostringstream problem with Xcode 3.2

Assuming you're using Xcode, try setting it to build as Release rather than Debug?

Yes I am using Xcode. And that worked! Thanks

10-26-2009, 02:33 AM	#1
epb Registered User Join Date: Oct 2009 Posts: 5	int to string - found method not working Hi, I tried the following code to convert an int to a string: Code: int i = 5678; string s; stringstream out; out << i; s = out.str(); But it returns an empty string! If I print the "out" variable using Code: cout << out << endl; It prints "0". What could possibly be wrong? I'm using Mac OS X 10.6.1 and gcc version 4.2.1.
epb is offline

10-26-2009, 05:06 AM	#2
laserlight C++ Witch Join Date: Oct 2003 Location: Singapore Posts: 10,368	Try printing s instead of out and you will probably find that out.str() did not return an empty string. __________________ C + C++ Compiler: MinGW port of GCC Build + Version Control System: SCons + Bazaar Look up a C/C++ Reference and learn How To Ask Questions The Smart Way
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10-26-2009, 05:39 AM	#3
joseCarlos Registered User Join Date: Oct 2009 Posts: 11	you can do lyke this int val=2635; char s[50]; cout<<itoa(val,s,10)<<endl; is that you want?
joseCarlos is offline

10-26-2009, 08:32 AM	#11
JacobN Registered User Join Date: Nov 2007 Posts: 29	According to this thread: Cocoabuilder - (Dmitry Markman) ostringstream problem with Xcode 3.2 Assuming you're using Xcode, try setting it to build as Release rather than Debug?
JacobN is offline

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