C# Files
Working With Files
The File class from the
System.IO namespace, allows us to work with files:
Example
using System.IO; // include the System.IO namespace
File.SomeFileMethod(); // use the file class with methods
The File class has many useful methods for creating and getting information
about files.
For example:
| Method | Description |
|---|---|
AppendText() |
Appends text at the end of an existing file |
Copy() |
Copies a file |
Create() |
Creates or overwrites a file |
Delete() |
Deletes a file |
Exists() |
Tests whether the file exists |
ReadAllText() |
Reads the contents of a file |
Replace() |
Replaces the contents of a file with the contents of another file |
WriteAllText() |
Creates a new file and writes the contents to it. If the file already exists, it will be overwritten. |
For a full list of File methods, go to Microsoft .Net File Class Reference.
Write To a File and Read It
In the
following example, we use the WriteAllText() method
to create a file named "filename.txt" and write some content to it. Then we use the ReadAllText()
method to read the contents of the file:
Example
using System.IO; // include the System.IO namespace
string writeText = "Hello World!"; // Create a text string
File.WriteAllText("filename.txt", writeText); // Create a file and write the content of writeText to it
string readText = File.ReadAllText("filename.txt"); // Read the contents of the file
Console.WriteLine(readText); // Output the content
The output will be:
Hello World!