Why does my program crash from an access violation after accepting user input?

Question

i get this strange error while ruining my program with Visual C++ 2008 Express Edition:

'Ex2.exe': Loaded 'D:\studyMA\c++\visual studio\Ex2\Ex2\Debug\Ex2.exe', Symbols loaded.
'Ex2.exe': Loaded 'C:\WINDOWS\system32\ntdll.dll'
'Ex2.exe': Loaded 'C:\WINDOWS\system32\kernel32.dll'
'Ex2.exe': Loaded 'C:\WINDOWS\WinSxS\x86_Microsoft.VC90.DebugCRT_1fc8b3b9a1e18e3b_9.0.30729.1_x-ww_f863c71f\msvcp90d.dll'
'Ex2.exe': Loaded 'C:\WINDOWS\WinSxS\x86_Microsoft.VC90.DebugCRT_1fc8b3b9a1e18e3b_9.0.30729.1_x-ww_f863c71f\msvcr90d.dll'
First-chance exception at 0x1049615e in Ex2.exe: 0xC0000005: 
    Access violation reading location 0x333ee91c.
Unhandled exception at 0x1049615e in Ex2.exe: 0xC0000005: 
    Access violation reading location 0x333ee91c.
The program '[948] Ex2.exe: Native' has exited with code 0 (0x0).

class product looks like this:

 using namespace std; 

 class product
 { 
 public: 
     string Product_code;
     string Product_Name;
     string Product_Category;
     string Product_Vendor;
     string Product_Discription;
     string Product_Group;

    void input();
    void clear_product_cell();
 };

I have one more class (contained in bomba.h) which contains:

     product ProductList[100];

I've written code in bomba.cpp, asking the user for input:

 char ch;
 cout << "Please Select your option: ";
 cin >> ch;

 switch(ch)
   {
     case '1'://Add a product
     {
        ProductList[0].input();
             :
             :
        :

product.cpp looks like this:

 product::input()

     do{
     cout << "Please enter product code: ";
     getline(cin,Product_code);
     if (Product_code.empty())
      cout << "You Must Enter A Code!!!";
    } while(Product_code.empty());
    cout << endl;

In the console, I get:

Please Select your option: 1 Please enter product code:

...and when I type a number and after the number I type the CR key the program crashes and I get the errors I quoted above.

Answer 1

A 0xC0000005, or access violation, indicates that you are trying to access memory that doesn't belong to your process. This usually means you haven't allocated memory.

Unfortunately you have provided too little code to say where things are going wrong but my guess would be that Product_code is uninitialised.

Answer 2

Without any information to go on ("Product_code is a member variable in class product" isn't very helpful), I'd guess that Product_code is null when you access it using .empty(), and that's causing the access violation. (I'm guessing based on the '0xC0000005' error code, but it is just a guess.)

Answer 3

what does Product_code look like after cin >> Product_code; ? it could be that Product_code.empty() is calling a function that doesnt exist because it is null

Answer 4

i solved the problem tnx anyway