How to use switch with character strings?

Question

I am trying to create a guessing game where if the player guesses one of many correct strings he will win. Although the switch statement will work with a single letter in the switch parenthesis but it wont work if i put my string in it.

#include "stdafx.h"
#include < iostream>

using namespace std;

class Player
{
public:

    void Guess();
};
void Guess()
{
char guess;
char* word1 = "Dog";
char* word2 = "Cat";


    cout <<"Welcome to guess the word. Get ready..." <<endl;
    cout <<"Guess the word: " <<endl;
    cin >>guess;

    for (int i = 0; i <= 3; i++) //give the player 3 trys at guessing
    {

    switch(guess)
        {
        case 'Dog':
            cout <<"Dog is correct." <<endl;
            i = 3;
            break;

        default:
            cout <<guess <<" is incorrect." <<endl;
            cin >>guess;




        }
    }
}

int main()
{
  Guess();
  char f;
  cin >>f;
  return 0;
}

Your code is very badly broken on many levels. It may be more productive to [read a good C++ book](http://stackoverflow.com/questions/388242/the-definitive-c-book-guide-and-list) first. — juanchopanza, Jan 01 '14 at 16:32

score 3 · Accepted Answer · answered Jan 01 '14 at 16:34

You cannot use switch with strings. This is incorrect:

case 'Dog': ...

Dog is a multibyte character constant, not a string. The compiler should issue a warning about it.

Moreover, guess is a single character. It needs to be a string as well. You should use std::string, like this:

std::string guess;
cout <<"Guess the word: " <<endl;
cin >>guess;
if (guess == "Dog") ...

score 2 · Answer 2 · answered Jan 01 '14 at 16:34

In C++, a switch statement can only compare basic data types, such as int or char. You would need to use a series of if statements to check whole strings, either using the equality operator (==) for std::string objects, or strcmp for C-style strings.

(Be careful not to use the equality operator for C-style strings, as that will only compare the pointer value and not the string content.)

Tobias · Answer 3 · 2014-01-01T17:45:37.980

1

Use std::string for the strings to compare.
Replace switch with if(...) { ... } else if(...) {...}

switch-case only works for integral types and 'Dog' is ~~not a single~~ a multi-byte character that could be converted to int but not a string. Note, that strings like "Dog" must be embraced in double-quotes.

edited Jan 01 '14 at 17:45

answered Jan 01 '14 at 16:30

Tobias

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“`'Dog'` is not a single character that could be converted to `int`.” Actually, it is, though the value is implementation-defined. – Jan 01 '14 at 16:49

How to use switch with character strings?

3 Answers3