FileStream.CanSeek FileStream.CanSeek FileStream.CanSeek FileStream.CanSeek Property

定义

获取一个值,该值指示当前流是否支持查找。Gets a value that indicates whether the current stream supports seeking.

public:
 virtual property bool CanSeek { bool get(); };
public override bool CanSeek { get; }
member this.CanSeek : bool
Public 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 falsetrue if the stream supports seeking; false if the stream is closed or if the FileStream was constructed from an operating-system handle such as a pipe or output to the console.

示例

下面的示例使用CanSeek要检查流是否支持查找属性。The following example uses the CanSeek property to check whether a stream supports seeking.

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
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

如果一个类派生自Stream不支持查找,则调用LengthSetLengthPosition,并Seek引发NotSupportedExceptionIf a class derived from Stream does not support seeking, calls to Length, SetLength, Position, and Seek throw a NotSupportedException.

如果流已关闭,此属性返回falseIf the stream is closed, this property returns false.

适用于

另请参阅