Stream.CanWrite Properti

Definisi

Ruang nama:

System.IO

Rakitan:

System.Runtime.dll

Sumber:

Stream.cs

Ketika ditimpa di kelas turunan, mendapatkan nilai yang menunjukkan apakah aliran saat ini mendukung penulisan.

public:
 abstract property bool CanWrite { bool get(); };

public abstract bool CanWrite { get; }

member this.CanWrite : bool

Public MustOverride ReadOnly Property CanWrite As Boolean

Nilai Properti

Boolean

true jika aliran mendukung penulisan; jika tidak, false.

Contoh

Berikut ini adalah contoh penggunaan CanWrite properti .

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.

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.

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.

Keterangan

Jika kelas yang berasal dari Stream tidak mendukung penulisan, panggilan ke Write, BeginWrite, atau WriteByte melempar NotSupportedException. Dalam kasus seperti itu, Flush biasanya diimplementasikan sebagai metode kosong untuk memastikan kompatibilitas penuh dengan jenis lain Stream karena valid untuk membersihkan aliran baca-saja.

Lihat juga

• I/O File dan Aliran
• Cara: Membaca Teks dari File
• Cara: Menulis Teks ke File