来自c ++中其他目录中文件的ifstream对象

Question

I have saved all of the files that I intend to use as input streams in my application in a folder called "res". I am trying to use these files as input streams by building the string in the application and then opening them using something like this:

....
ifstream inputFile;
....
char fileName[30];
strcpy(fileName,"res/")
switch(num){
case 1:
    strcat(fileName,"file1");
case 2:
    strcat(fileName,"file2");
....
}

inputFile.open(fileName);
....

But the files are not opening and I don't know why; the inputFile.is_open() method is returning false. So I have 2 questions:

1. How do I refer to files in sub-directories and, for that matter, files in other folders in the parent directory?

2. Is there a better practice than the one I am using for doing what I'm trying to do above?? I am pretty sure there is!

I am using eclipse CDT on Ubuntu 12.04, and the g++-4.6 compiler, if that makes a difference.

Answer 1

actually, right answer is given by david in comment. you forgot breaks after cases and concatenate multiple names. also with your mad skillz you better avoid strcat and other low-level functions and use std::string, or your next question will be about your program dumping core