FileStream.CanSeek Propriété
Définition
Important
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Obtient une valeur qui indique si le flux en cours prend en charge la recherche.
public:
virtual property bool CanSeek { bool get(); };
public override bool CanSeek { get; }
member this.CanSeek : bool
Public Overrides ReadOnly Property CanSeek As Boolean
Valeur de propriété
true
si le flux prend en charge la recherche ; false
si le flux est fermé ou si l'élément FileStream
a été construit à partir d'un handle de système d'exploitation comme un canal ou une sortie console.
Exemples
L’exemple suivant utilise la CanSeek
propriété pour case activée si un flux prend en charge la recherche.
using namespace System;
using namespace System::IO;
using namespace System::Text;
int main()
{
String^ path = "c:\\temp\\MyTest.txt";
// Delete the file if it exists.
if ( File::Exists( path ) )
{
File::Delete( path );
}
//Create the file.
FileStream^ fs = File::Create( path );
try
{
if ( fs->CanSeek )
{
Console::WriteLine( "The stream connected to {0} is seekable.", path );
}
else
{
Console::WriteLine( "The stream connected to {0} is not seekable.", path );
}
}
finally
{
if ( fs )
delete (IDisposable^)fs;
}
}
using System;
using System.IO;
using System.Text;
class Test
{
public static void Main()
{
string path = @"c:\temp\MyTest.txt";
// Delete the file if it exists.
if (File.Exists(path))
{
File.Delete(path);
}
//Create the file.
using (FileStream fs = File.Create(path))
{
if (fs.CanSeek)
{
Console.WriteLine("The stream connected to {0} is seekable.", path);
}
else
{
Console.WriteLine("The stream connected to {0} is not seekable.", path);
}
}
}
}
open System.IO
let path = @"c:\temp\MyTest.txt"
// Delete the file if it exists.
if File.Exists path then
File.Delete path
//Create the file.
do
use fs = File.Create path
if fs.CanSeek then
printfn $"The stream connected to {path} is seekable."
else
printfn $"The stream connected to {path} is not seekable."
Imports System.IO
Public Class Test
Public Shared Sub Main()
Dim path As String = "c:\temp\MyTest.txt"
' Delete the file if it exists.
If File.Exists(path) Then
File.Delete(path)
End If
'Create the file.
Dim fs As FileStream = File.Create(path)
If fs.CanSeek Then
Console.WriteLine("The stream connected to {0} is seekable.", path)
Else
Console.WriteLine("The stream connected to {0} is not seekable.", path)
End If
fs.Close()
End Sub
End Class
Remarques
Si une classe dérivée de Stream ne prend pas en charge la recherche, appelle , LengthSetLength, Positionet Seek lève un NotSupportedException.
Si le flux est fermé, cette propriété retourne false
.