How do I read in characters until the end (or right before the end) of a file?

Question

What I need to do:

Read a text file of type ifstream called textFile one character ch at a time until ch is equal to a single quotation mark '. If ch is never equal to a quotation mark, print out fail and break out of the loop.

//read a character from the file into ch;
textFile.get(ch);
            // while ch is not a single quote
            while (ch != '\'')
            {
                //read in another character
                textFile.get(c);

                if (textFile.peek(), textFile.eof())
                  {
                     cout << "FAIL";
                     break;
                  }
            }

The textFile.txt that I am reading from has NO single quotes, therefore the output should be FAIL.

However when I print it, it prints fail twice. Any help is appreciated

`if (textFile.peek(), textFile.eof())` Not sure what you expected this to do — Lightness Races in Orbit, Mar 12 '16 at 00:33

MikeCAT · Accepted Answer · 2016-03-12T00:53:03.020

ifstream::get(char& c) will return the ifstream object that is used to read, and it can be used as condition to check if the reading was successful. Use it.

Your code should be like this:

char c, ch;
// while ch is not a single quote
do
{
    //read in another character
    // you can use ch directly here and remove the assignment ch = c; below if you want
    if(!textFile.get(c))
    {
       cout << "FAIL";
       break;
    }
    ch = c;
} while(ch != '\'');

How do I read in characters until the end (or right before the end) of a file?

1 Answers1