C# Files

C# Files

In C#, file handling allows you to read, write, and manipulate files on the disk.
C# provides classes in the System.IO namespace for file operations.

Common File Classes in System.IO

Writing to a File

Using File.WriteAllText

Using StreamWriter

Reading from a File

Using File.ReadAllText

Using StreamReader

Appending to a File

File Info

Checking File Existence

Deleting a File

Common Mistakes

❌ Forgetting to include System.IO namespace
❌ Not using using statement (can cause file locks)
❌ Ignoring exceptions (use try-catch)

Summary

• Use File and FileInfo for file operations

• Use StreamReader / StreamWriter for reading/writing text

• Always check if file exists before reading/deleting

• Supports text, binary, append, and metadata operations