C Sharp (C#) - File IO
You want to create a backup of a file only if it exists, without overwriting an existing backup. Which code snippet correctly uses
File class static methods to do this?You want to create a backup of a file only if it exists, without overwriting an existing backup. Which code snippet correctly uses File class static methods to do this?
hard🚀 Application Q15 of 15
Step-by-Step Solution
Solution:
Step 1: Understand the requirements
Backup only if original file exists and do not overwrite existing backup file.Step 2: Analyze each option
if (File.Exists("file.txt")) File.Copy("file.txt", "backup.txt", true); overwrites backup.txt because of 'true' overwrite flag. if (File.Exists("file.txt") && !File.Exists("backup.txt")) File.Copy("file.txt", "backup.txt"); checks existence of both files and copies only if backup.txt does not exist. File.Copy("file.txt", "backup.txt"); copies without checks, risking errors or overwrites. File.Copy("file.txt", "backup.txt", false); copies without overwrite but does not check if original file exists.Final Answer:
if (File.Exists("file.txt") && !File.Exists("backup.txt")) File.Copy("file.txt", "backup.txt"); -> Option CQuick Check:
Check both files before copy to avoid overwrite [OK]
Quick Trick: Check both files exist before copying without overwrite [OK]
Common Mistakes:
MISTAKES- Not checking if backup file exists
- Using overwrite flag incorrectly
- Copying without checking original file existence
Master "File IO" in C Sharp (C#)
Want More Practice?
15+ quiz questions · All difficulty levels · Free
Free Signup - Practice All QuestionsMore C Sharp (C#) Quizzes