C Strings in Structures.

Hi, I'm sorry I don't have my actual code to show give an example, at this time, but I'll try to recreate my problem for you.

Using Dev C++ as a compiler, I found that if I define a character array in a structure and initialized the array inside of main I would get an "Invalid conversion from 'const char*' to 'char'" error.

Can anyone tell me why this is and how it could be fixed?

Here is some example code:

Code:

#include <iostream.h>

struct foo {
       char foofoo[10];   // I also tried " char foofoo[] "
       };

int main() {
    foo footwo;
    
    footwo.foofoo[4] = "Foo";   // I also tried just " footwo.foofoo " without
                                  // the array.    
    cout << footwo.foofoo;
    
    cin.get();
    
    return 0;   
}

Code:

10 |  C:\Documents and Settings\Owner\My Documents\Source Code\RPG.cpp  |  invalid conversion from `const char*' to `char'

You can't copy C-strings like this:

Code:

    footwo.foofoo[4] = "Foo";   // I also tried just " footwo.foofoo " without
                                  // the array.

They do not work like std::string. Instead, try strcpy.

Also note that footwo.foofoo[4] is a single character, not a string. Here is an example of how to use strcpy():
http://www.cplusplus.com/ref/cstring/strcpy.html

Code:

#include <iostream.h>

struct foo {
       char foofoo[10];
       };

int main() {
    foo footwo;
    
    strcpy (footwo.foofoo, "Foo");
      
    cout << footwo.foofoo;
    
    cin.get();
    
    return 0;   
}

This worked perfectly, thanks guys.

Also, I do understand that footwo.foofoo[4] is just the fourth value of the array. The logic just didn't hit me, at first. Thanks for pointing it out.

Also, I do understand that footwo.foofoo[4] is just the fourth value of the array. The logic just didn't hit me, at first. Thanks for pointing it out.

It's the 5th.

No nitpicking, my brain isn't functioning correctly.

Sorry, more nitpicking. Has anybody told you yet that you are using an out of date and non-standard header that doesn't exist on some modern compilers? You should be using <iostream> instead of <iostream.h>.

Also, why did you decide against the C++ string class? Your original code would have worked as expected.

Because I want it to output the text one letter at a time using a timer.

for instance:

Code:

int x = 0;

while ( footwo.foofoo[x] != '\0' ) {
    cout << footwo.foofoo[x];
    x = x + 1;

    timer();
}

...and I know iostream.h is antiquated, but I'm not really posting this code for anyone to compile, and it compiles fine on mine, so I wasn't really worried.

You can do that with the string class as well:

Code:

int x = 0;

while ( x < footwo.foofoo.length() ) {
    cout << footwo.foofoo[x];
    x = x + 1;

    timer();
}

Cool, then, it works good. Thank you.

You mean this line?

Code:

cout << footwo.foofoo[x];

The [x] there is necessary to only write out a single letter at a time. It behaves the same way for the string class as it does for a character array- outputting the character at position x.

The string type allows square brackets:

Code:

string s = "hippo";

cout << s[1];  // prints 'i'

[edit] ugh, beaten again [/edit]

*cough*

Code:

struct foo {
       char foofoo[10];   // I also tried " char foofoo[] "
       };

int main() {
    foo footwo = { "Foo" };
    
    cout << footwo.foofoo;
    
    cin.get();
    
    return 0;   
}

*cough*

Code:

#include <iostream>

using std::cout;
using std::cin;

Meh I just copied an modified his code. Plus the standard clause is in effect: If one posts a code to illustrate a point but doesn't include headers or silly little using declarations, it is the reader's responsiblity to add them in.