StreamReader and StreamWriter in .Net (C#)

StreamReader and StreamWriter classes are available in System.IO namespace. StreamWriter class used to write text (string) in file. StreamWriter class inherits from abstract TextWriter class. StreamReader class used to read text (string) from file. StreamReader class inherits from abstract TextReader class. 


Below are some useful methods of StreamReader and StreamWriter class.

Methods	Description
StreamWriter.Write	Writes text to file.
StreamWriter.WriteLine	Writes text to file, followed by line terminator.
StreamReader.Read	Reads text from file.
StreamReader.ReadLine	Reads line from file.

Read/Write text to file using StreamWriter.WriteLine and StreamReader.ReadLine

string[] names = new string[] { "Mitesh", "Jayesh", "Pritesh", "Kalpesh" };

void ReadWriteText()

{

    //write names to test.txt file

    using (StreamWriter sw = new StreamWriter(@"d:\Temp\Test.txt"))

    {

        foreach (string name in names)

            sw.WriteLine(name);

    }

    //read names from test.txt file

    using (StreamReader sr = new StreamReader(@"d:\Temp\Test.txt"))

    {

        string name = string.Empty;

        while ((name = sr.ReadLine()) != null)

        {

            Console.WriteLine(name);

        }

    }

}

Output –

Read/Write text from file using StreamReader.ReadLine and StreamWriter.Write

void ReadWriteText()

{

//write string/charactors to test.txt file

using (StreamWriter sw = new StreamWriter(@"d:\Temp\Test.txt"))

{

    foreach (char character in "Hello World!")

        sw.Write(character);

}

//read string/charactors from test.txt file

using (StreamReader sr = new StreamReader(@"d:\Temp\Test.txt"))

{

    string name = string.Empty;

    while ((name = sr.ReadLine()) != null)

    {

        Console.WriteLine(name);

    }

}

}

Output –

See Also - 
Working with performance counters in C#

How to create stopwatch application in WPF?

Working with ThreadPool in C#