QBASIC is an Integrated Development Environment (or IDE) and compiler for the BASIC programming language that was developed by Microsoft. QuickBASIC runs mainly on DOS, though there was also a short-lived version for the classic Mac OS. It is loosely based on GW-BASIC but adds user-defined types, improved programming structures, better graphics and disk support and a compiler in addition to the interpreter.
File Handling in QBASIC
01. What is a program file?
Ans: A file that has a set of instructions and can perform a task when it is executed is known as a program file.
02. What is a data file?
Ans: Data file is the collection of related data stored in memory.
03. What are the different modes of file handling?
Ans: The different file modes are listed below:
OUTPUT mode: To create a new data file and write data in it.
INPUT mode: To retrieve read the contents of the existing data file.
APPEND mode: To add more records to the existing file.
04. Functions and statements used in file handling:
INPUT statement: It is used to read the data of a sequential file and stores them in variable
LINE INPUT- statement: It reads an entire line from a sequential file and assign to a string variable.
EOF () Function: This function is used to check the end of file.
INPUT $ Function: It is used to return a part of a string from a file.
FILES statement: This statement displays a list of files of a disk or a directory.
KILL statement: This statement is used to delete files.
NAME statement: This statement renames a file.
CHDIR statement: This statement changes a drive’s default directory.
MKDIR statement: This statement creates a new directory or subdirectory
RMDIR statement: This statement removes a subdirectory (folder)
SHELL Command: This command is used to exit temporarily from the QBASIC environment to DOS prompt.
SYSTEM command: This command closes all the files and exits permanently from the QBASIC