[[email protected]]

Having trouble validating a file name. I am writing a program that reads in html file names and if it is valid it will store the title in a separate text file and I got everything else done except for this one park. If i enter nothing but valid file names everything works just fine but if it enter in invalid followed by a valid it keeps saying it is invalid.

I use a while loop "while ((isValid(my_file, file_name) == false))" to call a separate function isValid to check and see if it is valid and it works just fine in every situation except when I follow an invalid file with a valid and I have tried clearing it and it does not work and I cannot figure out what to do... Here is my code, I only included the main function and the isValid function the others are not important for this problem as far as I know.

//This function when called by main function will determine if file is valid
//It will do this by checking to make sure it ends in 'htm' and that the file exists
//and return true if it is a good file name and false if it is not.

//call library header file
#include "Libraries.h"

//declare function that will determine if file entered exists and is an html file using and ifstream and string parameter 
bool isValid(ifstream& file, string name)
{
	//use if statement to determine if file entered ends in 'htm' and if so it will return false
	//also will return false if file name entered does not even consist of 4 characters
	if ( (name.length() < 4) || (name.substr(name.length() - 4)) != (".htm"))
	{
		return false;
		
	}
	
	// another if statement that verifies file exists and if it does it returns true
	if (file.good())
	{
		return true;
		
	}

	// returns false if file does not exist
	else
	{
		return false;
	}

	//end function and header file
}


int main()
{
	//declare variable
	string file_name;
	
	//start infinite loop
	while (true)
	{
		//ask user for title and then store it in string and then change it to an ifstream
		cout <<"please enter a HTML file name or hit 'exit' to quit and " << endl; 
		cout << "if you want to clear file please enter 'clear': ";
		getline(cin,file_name);
		cout << "" << endl;
		ifstream my_file(file_name.c_str());
		
		//use if statement to determine if name entered was exit and if it was break out of infinite loop and end program
		if(file_name == "exit")
		{
			break;
		}

		//Use another if statement and it clear is entered call clear_file function and it will 
		// clear file, then notify you, and then continue back to top of loop
		if(file_name == "clear")
		{
			Clear_file();
			cout<< "You have just cleared you text file 'titles.txt'" << endl;
			cout <<"You may now continue running your program until you enter 'exit'." << endl;
			cout << "" << endl;
			continue;
			
		}
		
		//Use loop to call function isValid to see if it returned true or false, if false it will enter loop
		while ((isValid(my_file, file_name) == false))
		{
			
			//file_name.erase();
			//tell user file name was invalid and ask for another one amd keep asking and calling function to check if valid until valid name is given
			// and when one is store in string and convert to ifstream and exit loop
			cout <<"Invalid file name(must be an HTML(.htm)) file and it must exist." << endl;
			cout << "please enter a VALID file name: ";
			getline(cin,file_name);
			cout << "" << endl;
			//ifstream my_file(file_name.c_str());
		}
		
		// when it returns true call function to open file and then call output function(which in return will call another function to get
		// title of file and then the output function with output it to a text file)
		Open_file(file_name);
		Output_function(my_file);
		
		//close file when done and continue through loop until over and over again the word 'exit is entered.
		

		my_file.close();
		
	}

	//once user enters exit notify them that the program is done and all of the titles are stored in a separate file unless the cleared it
	cout << "" << endl;
	cout <<"Thank you for using this program! " << endl;
	cout << "Your titles are all stored in the file 'titles.txt', " << endl;
	cout << "unless you cleared that file.  Have a nice day!!" << endl;  
	cout << "" << endl;

	//pause and end program
	system("Pause");
	return 0;
}

[CTphpnwb]

You're checking the file name after you've attempted to open the file.