FileStream.CanSeek 属性
定义
重要
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获取一个值，该值指示当前流是否支持查找。
public:
virtual property bool CanSeek { bool get(); };public override bool CanSeek { get; }member this.CanSeek : boolPublic Overrides ReadOnly Property CanSeek As Boolean属性值
如果流支持查找，则为 true；如果流已关闭或者如果 FileStream 是从操作系统句柄（如管道或到控制台的输出）构造的，则为 false。
示例
下面的示例使用 属性 CanSeek 检查流是否支持寻找。
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);
}
}
}
}
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
注解
如果派生自 的类 Stream 不支持寻找，则调用 Length SetLength Position 、、 和 Seek ，并引发 NotSupportedException 。
如果流已关闭，则此属性返回 false 。