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class food- problem in debuging- in Destructor and toString

msadr (12)



1 problem in destructor :

Error : in file " dbgdel.cpp" on this code,it breaks in debuging with break -points

/* verify block type */
_ASSERTE(_BLOCK_TYPE_IS_VALID(pHead->nBlockUse));

************

Error : problem in Foods::toString ,in file " output.c " on ""while loop"" , it breaks in debugging with break-pionts.


{
if (text.sz == NULL) /* NULL passed, use special string */
text.sz = __nullstring;
p = text.sz;
while (i-- && *p)
++p;
textlen = (int)(p - text.sz); /* length of the string *
}
*****************

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class Foods
{
public:
	Foods(void);
	Foods(char* c, char* n, char* p);
	~Foods(void);
	
private:
	char* code;
	char* name;
	char* price;
	char* to_string;
	char* file_to_string;
	char** foods_pointers;

public:
	void setCode(char* c);
	void setName(char* n);
	void setPrice(char* p);
	
	char* getCode(void);
	char* getName(void);
	char* getPrice(void);
	char* getToString(void);
	char* getFileToString(void);
	char** getFoodsPointers(void);

	void init(char* c, char* n, char* p);
	void init(void);
	
	void toString(void);
	void print(void);
	
	int readFromFile(void);
	char* searchInFoods(char* food_code_to_search);
};

 

Foods::~Foods(void)
{
   
        if ( code!= NULL )
        {
            delete [] code;
            code = NULL;
        }
        ......
        ......
        .....
 }



Foods::Foods(void)
{
    price = NULL;
    name = NULL ;
    code = NULL;
    to_string = NULL;
    file_to_string = NULL;
    foods_pointers = NULL;
}


void Foods::setCode(char* c)
{  
       .....
       .....

         if ( Foods::searchInFoods (c) == "0")
        {
            code = strdup ( c );
        }
        else
        {
            cout << "This Food code is already exist\n\n";
            return;
        }

       .....
       .....
}



void Foods::toString()
{
    to_string = new char [100];        
    sprintf ( to_string, "%s\t\t%s\t\t%s\n", getCode(), getName(), getPrice() );
}
coder777 (8444)
strdup() is not a standard function.

it's very likely that malloc() is used to get the memory and hence you must use free() to discard it. Using delete in this case will fail
msadr (12)
why ? i didn't know it fail here, but why?
msadr (12)
why strdup is not standard ? what do you mean ?

so i must use strcpy () ? I think it's just like that
coder777 (8444)
malloc()/free() and new/delete are not compatible
msadr (12)
thanks too much
coder777 (8444)
yes, you need strcpy ().

Like so:
1
2
 
char *s = new[strlen(c) + 1]; // Note +1 for the terminating 0
strcpy (s, c);
msadr (12)
i used malloc and free,
the last problem in destructor ,not happend, but it breaks in another file,

it breaks in file " dbgheap.c" in part " if " from this code that i wrote below :


extern "C" static int __cdecl CheckBytes(
unsigned char * pb,
unsigned char bCheck,
size_t nSize
)
{
int bOkay = TRUE;
while (nSize--)
{
if (*pb++ != bCheck)
{
msadr (12)
thanks too much, the problem was from constructor with parametr, when i use it to make an object, before set every thing, i must call defult constructor in cinstructor with parametr to NULL every parameter.

I don't know why i must do that, but when i did this, it was no Error

thanks so mach.
coder777 (8444)
well yes, you must initialize a pointer otherwise you will face a crash.

From the code you showed here I cannot see what happend
msadr (12)
yes, it's true

thanks too much
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