3 replies to this topic

[LukeyJ]

Hi,

I'm getting an assertion error in the following script. I'm playing around with strings and trying to identify the string lengths of various ones. The first two worked great. When I tried to do the same thing dynamically. I ran into an assertion error which I am unfamiliar with. The output in the background works, but its taking a dislike to something.

Here is the code:

#include <string.h>

#include <iostream>


using namespace std;


int main () {

	char* str1 = "123456";

	char str2 [] = "123456789";

	char* pstr1 = NULL;

	pstr1 = new char[] = "1234567";


	cout << "Pointer to char length: " << strlen(str1) << endl

		<< "Array length: " << strlen(str2) << endl

		<< "Dynamic char array: " << strlen(pstr1) << endl;


	delete [] pstr1;

	pstr1 = NULL;


	return 0;

}

Any help would be greatly appreciated.

Thanks in advance,

Luke

[dcs]

Quote

main.cpp: In function `int main()':
main.cpp:10: error: expected primary-expression before ']' token

Are you sure it builds?

pstr1 = new char[] = "1234567";

Char arrays are not std::strings; use strcpy.

[LukeyJ]

The assertion error info I got was:

Debug Assertion Failed!

Expression: _BLOCK_TYPE_IS_VALID(pHead->nBlockUse)

It does compile for me, but throws and assert error. The error will perhaps be on one of the following lines.

	char* pstr1 = NULL;
	pstr1 = new char[] = "1234567";

<< "Dynamic char array: " << strlen(pstr1) << endl;

	delete [] pstr1;
	pstr1 = NULL;

pstr1 = new char[] = "1234567"; is my guess.

Can you initiatate new memory for a character array without specifying a size? Would new char* = "12345"; be a better course of action?

[dcs]

I thought I mentioned using strcpy.

#include <string.h>
#include <iostream>

using namespace std;

int main ()
{
   char* str1 = "123456";
   char str2 [] = "123456789";
   [COLOR="Blue"]char* pstr1 = new char[sizeof("1234567")];
   strcpy(pstr1, "1234567");[/COLOR]

   cout << "Length of string pointed to by str1: " << strlen(str1) << endl
        << "Size of str2: " << sizeof(str2) << endl
        << "length of string in str2: " << strlen(str2) << endl
        << "Dynamic char array: " << strlen(pstr1) << endl;

   delete [] pstr1;
   pstr1 = NULL;

   return 0;
}

/* my output
Length of string pointed to by str1: 6
Size of str2: 10
length of string in str2: 9
Dynamic char array: 7
*/

BTW, I wouldn't recommend doing

char* pstr1 = new char[[COLOR="Magenta"]sizeof("1234567")[/COLOR]];

I'm just being lazy.