Working With Files
The File class from the System.IO namespace, allows us to work with files:
Example
csharp
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
java
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!