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C#Files


Working With Files

TheFile class from theSystem.IO namespace, allows us to work with files:

Example

using System.IO;  // include the System.IO namespaceFile.SomeFileMethod();  // use the file class with methods

TheFile class has many useful methods for creating and getting information about files. For example:

MethodDescription
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 toMicrosoft .Net File Class Reference.



Write To a File and Read It

In the following example, we use theWriteAllText() method to create a file named "filename.txt" and write some content to it. Then we use theReadAllText() method to read the contents of the file:

Example

using System.IO;  // include the System.IO namespacestring writeText = "Hello World!";  // Create a text stringFile.WriteAllText("filename.txt", writeText);  // Create a file and write the content of writeText to itstring readText = File.ReadAllText("filename.txt");  // Read the contents of the fileConsole.WriteLine(readText);  // Output the content

The output will be:

Hello World!
Run example »



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