Append a number to set of characters

[aeo3]

Hello Everybody;
I would like to append a number to set of char, I do not like to use string, because In my project I am using several files.
What I did but there is a problem with it is as follows
1. char filename[30];
2. int x=2;
3. filename="xxxxx ";

But i do not know how to append 2 to filename.
Thanks

[Savage]

Hello Everybody;
I would like to append a number to set of char, I do not like to use string, because In my project I am using several files.
What I did but there is a problem with it is as follows
1. char filename[30];
2. int x=2;
3. filename="xxxxx ";

But i do not know how to append 2 to filename.
Thanks

What's seems to be the most logical way to you?

How would you do it with string?

Savage

[aeo3]

What's seems to be the most logical way to you?

How would you do it with string?

Savage

With string we can use a function strcpy, but with character variable it is not available to do this
I mean, I would like to change my filename within a loop
filename1.txt
filname2.txt ...etc

[Savage]

With string we can use a function strcpy, but with character variable it is not available to do this
I mean, I would like to change my filename within a loop
filename1.txt
filname2.txt ...etc

But you can have two cstrings(you are working in c,right?),one will contain base filename and second it's number converted to char array using itoa.After that you just append second string to the first,and there you have it.

Savage

[aeo3]

But you can have two cstrings(you are working in c,right?),one will contain base filename and second it's number converted to char array using itoa.After that you just append second string to the first,and there you have it.

Savage

I was tried to use itoa, but compiler complains, Also, i am using c++ with Cgywin complier

[Savage]

I was tried to use itoa, but compiler complains, Also, i am using c++ with Cgywin complier

Can you show us that line of code?

Savage

[aeo3]

Can you show us that line of code?

Savage

This is the new trial that i am trying to use string but there is many problems so I thought to use char

string int2string(const int& number)
{
  ostringstream oss;
  oss << number;
  return oss.str();
}
 
 
 
string FILENAME;
 
 for(int i=0;i<numEco;i++)
 {
    FILENAME="inf_h_";
    FILENAME+=int2string(h);
    FILENAME.append("_f_");
    FILENAME+=int2string(f);
    FILENAME.append("_");
    FILENAME+=int2string(i);
    FILENAME.append(".txt");
   // strcpy(str,FILENAME);
    EcoArray[i]->Run_Economy();
}
 

and here is an attempt but by using char

 int h=5;
 char filename[30]="inf_"
 filename=filename+h;

[sicarie]

aeo3-

Please use code tags around your code, they are [code=cpp] and [/code]

[Savage]

This is the new trial that i am trying to use string but there is many problems so I thought to use char

string int2string(const int& number)
{
  ostringstream oss;
  oss << number;
  return oss.str();
}
 
 
 
string FILENAME;
 
 for(int i=0;i<numEco;i++)
 {
    FILENAME="inf_h_";
    FILENAME+=int2string(h);
    FILENAME.append("_f_");
    FILENAME+=int2string(f);
    FILENAME.append("_");
    FILENAME+=int2string(i);
    FILENAME.append(".txt");
   // strcpy(str,FILENAME);
    EcoArray[i]->Run_Economy();
}
 

and here is an attempt but by using char

 int h=5;
 char filename[30]="inf_"
 filename=filename+h;

What are the problems with c++ strings?

If you want to use c style strings you cannot use operator+,if you try to use you will get something as :Invalid pointer arithmetic...

If you want to append then use strcat