How to Get File Info in C#: Simple Guide

In C#, you can get file information using the FileInfo class from System.IO. Create a FileInfo object with the file path, then access properties like Length, CreationTime, and Attributes to get details about the file.

Syntax

The FileInfo class provides properties and methods to get details about a file. You create an instance by passing the file path as a string to its constructor.

• FileInfo file = new FileInfo(string filePath); - creates a new FileInfo object for the file.
• Use properties like file.Length for size, file.CreationTime for creation date, and file.Attributes for file attributes.

csharp

using System.IO;

FileInfo file = new FileInfo("path/to/your/file.txt");
long size = file.Length;
DateTime created = file.CreationTime;
FileAttributes attrs = file.Attributes;

Example

This example shows how to get and print the size, creation time, and attributes of a file using FileInfo.

csharp

using System;
using System.IO;

class Program
{
    static void Main()
    {
        string filePath = "example.txt";

        // Create a sample file to ensure it exists
        if (!File.Exists(filePath))
        {
            File.WriteAllText(filePath, "Hello, world!");
        }

        FileInfo file = new FileInfo(filePath);

        Console.WriteLine($"File: {file.Name}");
        Console.WriteLine($"Size (bytes): {file.Length}");
        Console.WriteLine($"Created: {file.CreationTime}");
        Console.WriteLine($"Attributes: {file.Attributes}");
    }
}

Output

File: example.txt
Size (bytes): 13
Created: 6/1/2024 10:00:00 AM
Attributes: Archive

Common Pitfalls

Common mistakes when getting file info include:

• Using a file path that does not exist, which causes exceptions.
• Not handling exceptions like FileNotFoundException or UnauthorizedAccessException.
• Confusing FileInfo properties with static File class methods.

Always check if the file exists before accessing its info and use try-catch blocks to handle errors gracefully.

csharp

using System;
using System.IO;

class Program
{
    static void Main()
    {
        string filePath = "missing.txt";

        // Wrong way: no check, may throw exception
        // FileInfo file = new FileInfo(filePath);
        // Console.WriteLine(file.Length);

        // Right way:
        if (File.Exists(filePath))
        {
            FileInfo file = new FileInfo(filePath);
            Console.WriteLine(file.Length);
        }
        else
        {
            Console.WriteLine("File does not exist.");
        }
    }
}

Output

File does not exist.

Quick Reference

Property/Method	Description
Length	Gets the size of the file in bytes.
CreationTime	Gets or sets the creation date and time of the file.
LastAccessTime	Gets or sets the last access date and time.
LastWriteTime	Gets or sets the last write date and time.
Attributes	Gets or sets the file attributes (e.g., ReadOnly, Hidden).
Exists	Checks if the file exists (bool).
Delete()	Deletes the file.

Key Takeaways

Use the FileInfo class to get detailed information about a file in C#.

Always check if the file exists before accessing its properties to avoid exceptions.

FileInfo provides properties like Length, CreationTime, and Attributes for common file info.

Handle exceptions to manage cases like missing files or permission issues.

FileInfo objects are created by passing the file path to the constructor.