In C while editing the following code How can you check to s

In C++, while editing the following code. How can you check to see if the file is open or not. If not ask for the file name again untill they enter a valid txt file name. It needs to loop until a valid name is inputed.

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void Pokedex::readdata()

{  

   char filename[20];

   int i = 0;

   cout << \"What is the name of the file?(pokemon.txt): \";

   cin.getline(filename, 20);

   ifstream inputfile;

   inputfile.open(filename);

inputfile.get(creatures[i].name,SIZE,\',\');

   while(!inputfile.eof() && i < SIZE)

   {

       inputfile.ignore(SIZE, \',\');

       inputfile.get(creatures[i].type,SIZE,\',\');

       inputfile.ignore(SIZE,\',\');

       inputfile >> creatures[i].hitpoints;

       inputfile.ignore(SIZE, \',\');

       inputfile >> creatures[i].attack;

       inputfile.ignore(SIZE, \',\');

       inputfile >>creatures[i].defense;

       inputfile.ignore(SIZE, \',\');

       inputfile >>creatures[i].ability;

       inputfile.ignore(SIZE, \'\ \');

       ++i;

       ++count;

       inputfile.get(creatures[i].name,SIZE,\',\');          

   }

   cout << \"You have loaded \" << count <<\" pokemon.\";

   inputfile.close();

}

Solution

void Pokedex::readdata()
{
char filename[20];
int i = 0;
cout << \"What is the name of the file?(pokemon.txt): \";
cin>>filename;
ifstream inputfile;
inputfile.open(filename);
while(inputfile.fail())//checks whether file is opened or availble or not
   {
       inputfile.clear();
       cout<<\"file not found,please enter again:\";
       cin>>filename;
       inputfile.open(filename);
   }  
inputfile.get(creatures[i].name,SIZE,\',\');
while(!inputfile.eof() && i < SIZE)
{
inputfile.ignore(SIZE, \',\');
inputfile.get(creatures[i].type,SIZE,\',\');
inputfile.ignore(SIZE,\',\');
inputfile >> creatures[i].hitpoints;
inputfile.ignore(SIZE, \',\');
inputfile >> creatures[i].attack;
inputfile.ignore(SIZE, \',\');
inputfile >>creatures[i].defense;
inputfile.ignore(SIZE, \',\');
inputfile >>creatures[i].ability;
inputfile.ignore(SIZE, \'\ \');
++i;
++count;
inputfile.get(creatures[i].name,SIZE,\',\');
}
cout << \"You have loaded \" << count <<\" pokemon.\";
inputfile.close();
}