I have designed a linklist based BookStore in which book's attributes will be stored in a node & so on. Plus at the end of program, I have to save all database into text file *(I tried binary reading but damn I got me killed & couldn't do it)* & then reload all info, of each book one by one & store it in nodes & re-make the LinkList.
Now saving is done & no issue at all. But Im having issues in reading from text file.
Saving structure in file is:::
BookID(int) - BookName(string) - Author(string) - BookType(string) - Copies(long) - Price(long) - '\n' (to go to next line)
1 ObjectOrientedParadigm R.Lafore Coding 5 900
2 ObjectOrientedParadigm R.Lafore Coding 5 900
and so on......
Here is the saving function.
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if(!is_Empty()) //if list is not empty
BOOK<mytype> *temp = head; //created a copy of head
ofstream file("database.txt", ios_base::app); //created file, to write at the end (append)
while(temp != tail) //while list ends
file<<temp->ID<<' '<<temp->bookName<<' '<<temp->author<<' '<<temp->book_type<<' '<<temp->copies<<' '<<temp->price<<' '; //write all info
temp = temp->next; //move temp to next node
file<<temp->ID<<' '<<temp->bookName<<' '<<temp->author<<' '<<temp->book_type<<' '<<temp->copies<<' '<<temp->price<<' '; //for last book's info
returntrue; //to confirm sucessfull writing
else //if list is empty
returnfalse; //to confirm error in writing
PROBLEM:: When I start reading, first line is read fine & stored in list, but for the next time, I can't make file to read from the next line, hence '\n'. & that creates the problem. File again reads the first line & 2nd node is created with same data.
int ID; //variable to store ID of a book
string bookName;//string to store name of a book
string author; //string to store name of author of book
string book_type;//string to store type of a book
long copies; //variable to store no. of copies a book
long price; //variable to store price of a book
string status; //to store status of a book, either its in stock or not
while(file) //I have tried file.eof but its not working, don't know why
file>>ID>>bookName>>author>>book_type>>copies>>price>>status; //read file
BOOK<mytype> *temp = new BOOK<mytype>(0, 0, bookName, author, book_type, copies, price); //create a new node in memory and save all the data
if(is_Empty()) //if list is empty, then make 1st node
head = tail = temp;
else //other wise make the next node
tail->next = temp;
temp->prev = tail;
tail = temp;
Reading is done 1 time less than the real record. i.e. If .txt has record of 4 books, then 3 nodes are created, (& info of only 1st is repeated in every node), whereas it should read & create 4 nodes!
Im a beginner, any good help will be much appreciated. Luv All!
Its solved. & Im not using getline to input strings, just cin>> .
1. I used stringstream mystr (#include<sstream>)
2. I was trying to read bookstatus in load function which was WRONG.
3. correct while condition -> while(file>>ID>>bookName>>author>>book_type>>copies>>price)
4. Into while, correct reading ->> mystr>>ID>>bookName>>author>>book_type>>copies>>price;