StreamReader Class
Reads characters from a stream in a particular encoding.
Namespace:
Assembly:
mscorlib.dll (in mscorlib.dll)
Inheritance
Object > TextReader > StreamReader
Remarks
The StreamReader class supports seeking.
StreamReader is used to read from any stream that can seek and is less than 4 gigabytes in size.
You can use StreamReader to read from a FileStream or any other stream that supports seeking.
If the underlying stream is not readable, or if the stream has been closed, StreamReader throws an ArgumentException.
Constructors
The StreamReader class has the following constructors:
| Constructor | Description |
|---|---|
| StreamReader(Stream stream) | Initializes a new instance of the StreamReader class for the specified stream and detects the encoding of the input data. |
| StreamReader(Stream stream, bool detectEncodingFromByteOrderMarks) | Initializes a new instance of the StreamReader class for the specified stream, with an option to detect encoding. |
| StreamReader(string path) | Initializes a new instance of the StreamReader class for the specified file path. |
| StreamReader(string path, System.Text.Encoding encoding) | Initializes a new instance of the StreamReader class for the specified file path and character encoding. |
Methods
The StreamReader class has the following public methods:
| Method | Description |
|---|---|
| Close() | Closes the underlying stream and the StreamReader object. |
| DiscardBufferedData() | Clears the internal buffer. |
| Peek() | Returns the next available character, but does not consume it from the input stream. |
| Read() | Reads the next character from the input stream and advances the character position by one. |
| Read(char[] buffer, int index, int count) | Reads a specified maximum number of characters from the current stream and writes the data to a buffer, starting at the given index. |
| ReadToEnd() | Reads all characters from the current position to the end of the stream and returns them as one string. |
Example
using System;
using System.IO;
using System.Text;
public class Example
{
public static void Main()
{
string filePath = @"C:\temp\mytextfile.txt";
try
{
// Create a file to write to
using (StreamWriter sw = File.CreateText(filePath))
{
sw.WriteLine("This is the first line.");
sw.WriteLine("This is the second line.");
}
// Create a StreamReader to read the file
using (StreamReader sr = new StreamReader(filePath, Encoding.UTF8))
{
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)
{
Console.WriteLine("The process failed: {0}", e.ToString());
}
}
}