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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
public abstract bool CanWrite { get; }
public: virtual property bool CanWrite { bool get () abstract; }
abstract CanWrite : bool
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, _ FileAccess.Write) If fs.CanRead And fs.CanWrite Then Console.WriteLine("MyFile.txt can be both written to and read from.") Else 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.
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.
using namespace System; using namespace System::IO; int main() { FileStream^ fs = gcnew 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: 4.5, 4, 3.5, 3.0, 2.0, 1.1, 1.0.NET Framework Client Profile
Supported in: 4, 3.5 SP1Portable Class Library
Supported in: Portable Class LibraryWindows 8 Release Preview, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 SP2, Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.