C# StreamWriter

In c#, StreamWriter is a class of System.IO namespace and it is useful to write characters to the stream with a particular encoding. The StreamWriter class has been derived from TextWriter to provide the implementation of members for writing to a stream and by default, it will use UTF8Encoding unless we specify other encodings.


Now, we will see how to use the StreamWriter class in c# to write a text to the file with examples.

C# StreamWriter Example

Following is the example of writing a text to file using the StreamWriter object in c#.


using System.IO;


namespace TutlaneExamples


    class Program


        static void Main(string[] args)


            string fpath = @"D:\Test.txt";

            // Check file if exists

            if (File.Exists(fpath))




            // Create the file

            FileStream fs = new FileStream(fpath, FileMode.Create);

            using (StreamWriter sw = new StreamWriter(fs))



                sw.WriteLine("\r\nWelcome to Tutlane");

                sw.WriteLine("\r\nStreamWriter Example");





If you observe the above example, we imported a System.IO namespace in our example to access File, FileStream & StreamWriter objects to delete, create and write a text to file.


When we execute the above example, it will create a new “Test.txt” file in D drive with required text like as shown following.


C# StreamWriter Example Result


This is how we can create, delete and add text to files using File, FileStream & StreamWriter objects in c#.

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