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Stream.CanWrite Property

When overridden in a derived class, gets a value indicating whether the current stream supports writing.

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

public abstract bool CanWrite { get; }

Property Value

Type: System.Boolean
true if the stream supports writing; otherwise, false.

If a class derived from Stream does not support writing, a call to Write, BeginWrite, or WriteByte throws a NotSupportedException.

If the stream is closed, this property returns false.

The following is an example of using the CanWrite property.

using System;
using System.IO;

class TestRW 
{
  public static void Main(String[] args)
  { 
    FileStream fs = new FileStream("MyFile.txt", FileMode.OpenOrCreate,
       FileAccess.Write);
    if (fs.CanRead && fs.CanWrite) {
        Console.WriteLine("MyFile.txt can be both written to and read from.");
    }
    else if (fs.CanWrite) {
        Console.WriteLine("MyFile.txt is writable.");
    }
  }
}
//This code outputs "MyFile.txt is writable." 
//To get the output message "MyFile.txt can be both written to and read from.",
//change the FileAccess parameter to ReadWrite in the FileStream constructor.

.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

Portable Class Library

Supported in: Portable Class Library

Supported in: Windows Phone 8.1

Supported in: Windows Phone Silverlight 8.1

Supported in: Windows Phone Silverlight 8
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