Was this page helpful?
Your feedback about this content is important. Let us know what you think.
Additional feedback?
1500 characters remaining
Export (0) Print
Expand All

StreamWriter Constructor (Stream)

Initializes a new instance of the StreamWriter class for the specified stream by using UTF-8 encoding and the default buffer size.

Namespace:  System.IO
Assemblies:   mscorlib (in mscorlib.dll)
  System.IO (in System.IO.dll)

public StreamWriter(
	Stream stream
)

Parameters

stream
Type: System.IO.Stream

The stream to write to.

ExceptionCondition
ArgumentException

stream is not writable.

ArgumentNullException

stream is null.

This constructor creates a StreamWriter with UTF-8 encoding without a Byte-Order Mark (BOM), so its GetPreamble method returns an empty byte array. The default UTF-8 encoding for this constructor throws an exception on invalid bytes. This behavior is different from the behavior provided by the encoding object in the Encoding.UTF8 property. To specify whether an exception is thrown on invalid bytes, use a constructor that accepts an encoding object as a parameter, such as StreamWriter. The BaseStream property is initialized using the stream parameter. The position of the stream is not reset.

The StreamWriter object calls Dispose() on the provided Stream object when StreamWriter.Dispose is called.

Caution noteCaution

When you compile a set of characters with a particular cultural setting and retrieve those same characters with a different cultural setting, the characters might not be interpretable and could cause an exception to be thrown.

For a list of common I/O tasks, see Common I/O Tasks.

The following code example demonstrates this constructor.

using System;
using System.IO;

namespace ConsoleApplication
{
    class Program
    {
        static void Main(string[] args)
        {
            string fileName = "test.txt";
            string textToAdd = "Example text in file";
            FileStream fs = null;
            try
            {
                fs = new FileStream(fileName, FileMode.CreateNew);
                using (StreamWriter writer = new StreamWriter(fs))
                {
                    writer.Write(textToAdd);
                }
            }
            finally
            {
                if (fs != null)
                    fs.Dispose();
            }
        }
    }
}

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0, 1.1

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

XNA Framework

Supported in: 3.0, 2.0, 1.0

.NET for Windows Phone apps

Supported in: Windows Phone 8.1, Windows Phone Silverlight 8.1, Windows Phone Silverlight 8

Portable Class Library

Supported in: Portable Class Library
Show:
© 2015 Microsoft