Stream.CanWrite
Property
Definition
When overridden in a derived class, gets a value indicating whether the current stream supports writing.
public abstract bool CanWrite { get; }
Property Value
true if the stream supports writing; otherwise, false.
Examples
The following is an example of using the CanWrite property.
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
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.
Remarks
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.