using string with ints?

[jimberger]

hello i am trying to create an appended string

int i = 5;
char * ch = 3;
string st;

can i do....

st += ch;
st += i;

that is, append a integer or another data type to a string like this..
i know i can use sstream to do this but i need to be able to use string.

cheers

 

[Zyrenthian]

I would format using sprintf (havent used "string" in a while and you may need to get a writeable buffer, i forget)

sprintf(string,"%c%d",ch,i);

Matt

 

[PerFnurt]

If possible I'd still recommend sstream, as its the C++ way to do it, which type checks and so on.

sprintf has no type checking at all.

>i need to be able to use string.

sstream to string is trivial

/Per

_{"It was a work of art, flawless, sublime. A triumph equaled only by its monumental failure."}

 

[uolj]

sprintf doesn't work with string anyway. And char * ch = 3; is not right either. You'll just have to use a stringstream if you use a string. Note that even eith c-style strings you cannot use += either, you must use strcat or sprintf.

 

[chipperMDW]

> i know i can use sstream to do this but i need to be able to use string.

sstream (i.e. stringstream) is string-based. You just haven't looked at a reference for how to use it.

So:

stringstream s;

s << 5 << " bleat " << 4.78 << '?';

string str = s.str();

/* ... */

string woof( "I like eating " );

stringstream r( woof );

r << get_num_cats() << " cats a day\n";

 

[ArkM]

There is a very strange code in the 1st post:

char * ch = 3;

Assign int to pointer?...
Proposed 'solution

sprintf(string,"%c%d",ch,i);

crashes your string, that's all...
Use sprintf via temp buffer:

void operator +=(string& s, int i)
{
  char temp[12];
  sprintf(temp,"%d",i);
  s += temp;
}

Now you may use string += int as you wish...