CanWrite Property

Stream.CanWrite Property


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

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

Public MustOverride ReadOnly Property CanWrite As Boolean

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.

Imports System
Imports System.IO

Class TestRW    

    Public Shared Sub Main()
        Dim fs As New FileStream("MyFile.txt", FileMode.OpenOrCreate, _
        If fs.CanRead And fs.CanWrite Then
            Console.WriteLine("MyFile.txt can be both written to and read from.")
            If fs.CanWrite Then
                Console.WriteLine("MyFile.txt is writable.")
            End If
        End If
    End Sub
End Class

'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.

Universal Windows Platform
Available since 4.5
.NET Framework
Available since 1.1
Portable Class Library
Supported in: portable .NET platforms
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1
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