Const string arrays

[Toe001]

Can you please help me understand why I do not see the answer expected (Parity: Odd). Can I have an array of strings as constants? How do I index each string in the array?

const Parity[3] = {'None', 'Odd', 'Even'};
char string[];

sprintf(string, "Parity: %s", Parity[1]);
printf(string);

Thanks

[RRick]

You got the right idea but your code has syntax problems. Does this compile for you? I doubt it.

Your Parity definition says its a "const Parity" but it does not tell the compiler what it is ( i.e. int, char, pointer to something?) Put that something between the const and Parity. Also, use the double quote instead of the single quote for strings. The single quote defines a single char, not a string.

Finally, your string variable needs some size. Pick a value bigger than the largest string in Parity.

[Toe001]

Thank you for the help.

Yes it did compile without errors (it is a Z8 micro compiler), so this is why I was confused!

I have followed your suggestions and changed to:

const char Parity[3][4] = {"None", "Odd", "Even"};
char string[];

sprintf(string, "Parity: %s", Parity[1]);
printf(string);

And it now seems to work. However, this does not seem very elegant to have to use a multi-dimension array to hold these three constants (strings), is there a better way? Maybe I should I be using ennumerated types rather?

[weaknessforcats]

If you don't need the items as strings, then an enum is the way to go.

All an enum is a list of named integer values. You use enums to avoid hard-coded values in your program:

enum Value {NONE, ODD, EVEN}; 
 
if (something == ODD)
{
  //etc...
}
 

Since an enum is a named integer value and not an actual integer, an enum is a declaration and that means you can put it in a header file and use it in all of your source files.

[Toe001]

Thank you for this further explanation of enum types. It seems a better way to go about things and I will try this.

For my education - and I am a beginner - can one not have in C a simple array with three elements to hold three strings, and so as not to allow these strings to be altered, add the qualifier "const". Something like:

const char Parity[3] = {"None", "Odd", "Even"};

It seems straight forward, but does not work?

I would expect Parity[1] to hold the string "Odd" etc.

Thanks

[ilikepython]

Thank you for this further explanation of enum types. It seems a better way to go about things and I will try this.

For my education - and I am a beginner - can one not have in C a simple array with three elements to hold three strings, and so as not to allow these strings to be altered, add the qualifier "const". Something like:

const char Parity[3] = {"None", "Odd", "Even"};

It seems straight forward, but does not work?

I would expect Parity[1] to hold the string "Odd" etc.

Thanks

Each element is a char so 1 letter. You need an array of char *s:

char *Parity[3] = {"None", "Odd", "Even"};
 

[Toe001]

Aah, now I understand!

Thank you all.