How to: Read Text from a File
.NET Framework 3.0
The following code examples show how to read text from a text file. The second example notifies you when the end of the file is detected. This functionality can also be achieved by using the ReadAllLines or ReadAllText methods.
Example
using System; using System.IO; class Test { public static void Main() { try { // Create an instance of StreamReader to read from a file. // The using statement also closes the StreamReader. using (StreamReader sr = new StreamReader("TestFile.txt")) { String line; // Read and display lines from the file until the end of // the file is reached. while ((line = sr.ReadLine()) != null) { Console.WriteLine(line); } } } catch (Exception e) { // Let the user know what went wrong. Console.WriteLine("The file could not be read:"); Console.WriteLine(e.Message); } } }
using System; using System.IO; public class TextFromFile { private const string FILE_NAME = "MyFile.txt"; public static void Main(String[] args) { if (!File.Exists(FILE_NAME)) { Console.WriteLine("{0} does not exist.", FILE_NAME); return; } using (StreamReader sr = File.OpenText(FILE_NAME)) { String input; while ((input=sr.ReadLine())!=null) { Console.WriteLine(input); } Console.WriteLine ("The end of the stream has been reached."); sr.Close(); } }
Robust Programming
This code creates a StreamReader that points to MyFile.txt through a call to File.OpenText. StreamReader.ReadLine returns each line as a string. When there are no more characters to read, a message is displayed to that effect, and the stream is closed.
Note |
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| Visual Basic users may choose to use the methods and properties provided by the My.Computer.FileSystem object for file I/O. For more information, see My.Computer.FileSystem Object. |
See Also
Tasks
How to: Create a Directory ListingHow to: Read and Write to a Newly Created Data File
How to: Open and Append to a Log File
How to: Write Text to a File
How to: Read Characters from a String
How to: Write Characters to a String
Reference
StreamReaderFile.OpenText
StreamReader.ReadLine
Concepts
Basic File I/OCommunity Additions
ADD
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