Programming Question c++: How to add a number after a \0 in a char array?

[Topper]

Hello,
i want to parse a connected char array to an array of strings.
In the char array, '\0' is used to seperate the string.
After the '\0' is a number, in this case 456.
The problem is that \0456 will be replaced by the assci sign 456.
So how I can initialize the char array right instead of this?:






Background:

char charArray[]  = "ABC\0456\0"
void getStringArraysFromCharArray()
{  
  
  int n_woerter = 0;
  for (int i=0; i<sizeof(charArray); i++)
  {
    if (charArray[i] == '\0') n_woerter++;
  }
  String *woerter = new String[n_woerter];
  int d_ptr = 0;
  
  for (int i=0; i<n_woerter; i++)
  {
    woerter[i].concat(&charArray[d_ptr]);
    d_ptr += woerter[i].length() + 1;
  }
...
}

 

[Urwumpe]

You mean: Not escaping the number with the \nnnnn? What about using a \u0000 there instead of a \0?

\0456 is not turned into unicode, btw, but interpreted as octal byte. How the result looks like depends on the compiler though, since you are using a value too large for a byte in that example. \x00 would also work maybe, but again, you could get compiler specific issues, since \x00456 could still be a legal 32bit character...

Or alternative: Use a different delimiter if allowed.

 

[kuddel]

I would let the preprocessor's string-literal concatenation work for you:

char foo[] = "Hello" "-" "World"; // equals: "Hello-World" (+ terminating zero)

so for your casse

char charArray[] = "ABC\0" "456\0";

The 2nd "\0" (after your three-digit number) is redundant however,
but it is needed in case you don't know the array size at compile-time.
Then a "terminating-zero" indicates a word delimiter and the "double-terminating-zero" indicates the end of list. Microsoft Foundation Classes (MFC) resources used this technique a lot in list initializers (.rc files).

---------- Post added at 21:46 ---------- Previous post was at 21:44 ----------

Memory looks like this then:

41 42 43 00 34 35 36 00 00 | ABC.456..

---------- Post added at 21:49 ---------- Previous post was at 21:46 ----------

The preprocessor's string-literal concatenation also has the nice benefit of letting you do a more "logical" formatting of your words, like:

char input[] =
  "First\0"
  "Second\0"
  "3rd\0"
  "last";

 

[Topper]

@Urwumpe, if I replace the delimiter by another one, String.concat would not work anymore...
I also tried the other solutions, they also not work, because i gues e.g. "\0x00456" is also a valid hex code or isnt it?



kuddel that solution works.


Thank you!

 

[kuddel]

And while we're at it, I would do the splitting a little different:

#include<vector>

char charArray[] = "ABC\0" "456\0"; // the last zero is *ESSENTIAL* here!

void splitStringList ()
{
	std::vector<std::string> words;
	const char* p = charArray;
	do {
		words.push_back(std::string(p));
		p += words.back().size() + 1;
	} while (*p != 0);
	// ...
}