C++ create string of text and variables

c++ string variables std
Jack Farrow picture Jack Farrow · Apr 19, 2012 · Viewed 141.4k times · Source

I'm trying to do something very simple and yet, after an hour of so of searching a I can't find a suitable answer so I must be missing something fairly obvious.

I'm trying to dynamically create filenames for use with ifstream. Whilst I understand various methods are available of doing this, I have settled on creating a std::string, and the using stringname.c_str to convert to const.

The problem is however that I need to create the string with a mix of variables and predefined text values. I'm getting compiler errors, so this must be a syntax issue.

Pseudo 

std::string var = "sometext" + somevar + "sometext" + somevar;

Thanks!

Answer

mgiuffrida picture mgiuffrida · Apr 19, 2012

Have you considered using stringstreams?

#include <string>
#include <sstream>

std::ostringstream oss;
oss << "sometext" << somevar << "sometext" << somevar;
std::string var = oss.str();

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