I have to assign int values from arrays to a string so I can use the string to display output.
Im getting errors, and I cant find any information in my book or on the web how to do this. If you can just provide me with a tutorial link on how to do this Id be grateful.Code:string Polygon::ShowPolygon() { string displayPoly; for (int h = 0;h < num_points;h += 2) { displayPoly += "(" + points[h] + "," + points[h + 1] + ")"; if (h < num_points) displayPoly += ","; } return displayPoly; }
It helps if you post your errors.
http://faq.cprogramming.com/cgi-bin/...&id=1043284385
printf() outputs to the standard output.
_snprintf() is another useful function
Try to help all less knowledgeable than yourself, within
the limits provided by time, complexity and tolerance.
- Nor
Nor- here is the entire program with error output on the bottomOriginally Posted by Nor
http://codepad.org/TLWDe1ey
Which would be nice if I was using C, but Im using C++, and the little I know about C string functions only makes me wonder how the most used procedural language in the world does not have safe/fault tolerant IO by default.
Last edited by shintaro; 11-20-2008 at 09:49 PM.
Use a std::stringstream in place of the sprintf family of functions:
Code:#include <sstream> ... string Polygon::ShowPolygon() { std::stringstream displayPoly; for (int h = 0;h < num_points;h += 2) { displayPoly << "(" << points[h] << "," << points[h + 1] << ")"; if (h < num_points) displayPoly << ","; } return displayPoly.str(); }
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-Christopher Hitchens
hk_mp5kpdw- I appreciate the help, but there has got to be an easy(er) way to do this without resorting to exotic functions that my teacher has never heard of. Time for me to crack more books and see if I can find an instance of ints being assigned to a string.
Edit: I think the problem is that I cant concat an int with strings when assigning to a string. Im taking a Java and C++ class at the same time, I think Im getting stuff mixed up between these languages.
sry for not explaining clearly what I wanted
Last edited by shintaro; 11-20-2008 at 11:26 PM.
std::stringstream is part of the C++ standard. it is not exotic. It is the easiest way to do what you want.
stringstream is what you want.
Another possibility is that ShowPolygon is supposed to output directly to cout instead of creating a string. In that case you don't have to convert an int to a string because you can just send the ints to the output stream directly.
Raigne, Daved- Yes youre right, after some looking I came across info on converting numbers to strings. So I guess this is what I will have to put in my code:
Daved- the function has to return a string, so I cant do output inside the function.Code:double c; c = -3.4; ostringstream cnvrt; cnvrt << c; s = cnvrt.str();
thanks all
