Reading a text file that contains a number and a string

Question

I am new to C++ and I am currently exploring things. Now I am on reading a text file. This is the code:

while (myfile.good()) {
        myfile >> tempNum;
        getline(myfile, tempName);
        getline(myfile, tempCourse);
        myfile >> tempTuition;
        if (myfile.eof()) break;
        Student temp(tempNum, tempName, tempCourse, tempTuition);
        students.push_back(temp);
    }

Now my file currently contains this:

201699856
Justin Chu
BSITDA
36889

Problem is, with my current code, it reads like this.

tempNum = 201699856
tempName = ""
tempCourse = "Justin Chu"
tempTuition = "BSITDA"

At tempTuition, my program freezes because it contains an invalid data. Why is the getline() skipping the 2nd line? And how can I fix the program to read correctly?

You loop is almost equivalent to `while(!myfile.eof())`, so please read [Why is iostream::eof inside a loop condition considered wrong?](https://stackoverflow.com/questions/5605125/why-is-iostreameof-inside-a-loop-condition-considered-wrong) — Some programmer dude, Feb 26 '18 at 12:30
Also see [How does reading file with while loops work in C++?](https://stackoverflow.com/q/14009737/608639) and [Why is iostream::eof inside a loop condition considered wrong?](https://stackoverflow.com/q/5605125/608639) — jww, Feb 26 '18 at 12:38
Thanks for the links. So I saw that you can chain the input like while(stream>>variable>>variable). But how will it work for variables that has an int and a string? String when read, gives a single word with no whitespace. — Ryon, Feb 27 '18 at 09:15

score 0 · Answer 1 · edited Feb 26 '18 at 12:44

0

From std::getline:

When used immediately after whitespace-delimited input, e.g. after int n; std::cin >> n;, getline consumes the endline character left on the input stream by operator>>, and returns immediately. A common solution is to ignore all leftover characters on the line of input with cin.ignore(std::numeric_limits<std::streamsize>::max(), '\n'); before switching to line-oriented input.

edited Feb 26 '18 at 12:44

Arnav Borborah

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answered Feb 26 '18 at 12:36

zteffi

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Is this applicable to reading lines in text file? I mean the cin.ignore() part? – Ryon Feb 27 '18 at 08:58

Reading a text file that contains a number and a string

1 Answers1