SeekOrigin Enumeração

Definição

Especifica a posição em um fluxo a ser usada para busca.Specifies the position in a stream to use for seeking.

public enum class SeekOrigin
public enum SeekOrigin
[System.Serializable]
public enum SeekOrigin
[System.Serializable]
[System.Runtime.InteropServices.ComVisible(true)]
public enum SeekOrigin
type SeekOrigin = 
[<System.Serializable>]
type SeekOrigin = 
[<System.Serializable>]
[<System.Runtime.InteropServices.ComVisible(true)>]
type SeekOrigin = 
Public Enum SeekOrigin
Herança
SeekOrigin
Atributos

Campos

Begin 0

Especifica o início de um fluxo.Specifies the beginning of a stream.

Current 1

Especifica a posição atual em um fluxo.Specifies the current position within a stream.

End 2

Especifica o final de um fluxo.Specifies the end of a stream.

Exemplos

O exemplo a seguir mostra como ler para trás ao final do fluxo e como ler a partir de um ponto especificado no fluxo.The following example shows how to read backwards starting at the end of the stream, and how to read from a specified point in the stream.

using System;
using System.IO;

public class FSSeek
{
    public static void Main()
    {
        long offset;
        int nextByte;

        // alphabet.txt contains "abcdefghijklmnopqrstuvwxyz"
        using (FileStream fs = new FileStream(@"c:\temp\alphabet.txt", FileMode.Open, FileAccess.Read))
        {
            for (offset = 1; offset <= fs.Length; offset++)
            {
                fs.Seek(-offset, SeekOrigin.End);
                Console.Write(Convert.ToChar(fs.ReadByte()));
            }
            Console.WriteLine();

            fs.Seek(20, SeekOrigin.Begin);

            while ((nextByte = fs.ReadByte()) > 0)
            {
                Console.Write(Convert.ToChar(nextByte));
            }
            Console.WriteLine();
        }
    }
}
// This code example displays the following output:
//
// zyxwvutsrqponmlkjihgfedcba
// uvwxyz
Imports System.IO

Public Class FSSeek
    Public Shared Sub Main()
        Dim offset As Long
        Dim nextByte As Integer

        ' alphabet.txt contains "abcdefghijklmnopqrstuvwxyz"
        Using fs As New FileStream("c:\temp\alphabet.txt", FileMode.Open, FileAccess.Read)

            For offset = 1 To fs.Length
                fs.Seek(-offset, SeekOrigin.End)
                Console.Write(Convert.ToChar(fs.ReadByte()))
            Next offset
            Console.WriteLine()

            fs.Seek(20, SeekOrigin.Begin)

            nextByte = fs.ReadByte()
            While (nextByte > 0)
                Console.Write(Convert.ToChar(nextByte))
                nextByte = fs.ReadByte()
            End While
            Console.WriteLine()

        End Using
    End Sub
End Class

' This code example displays the following output:
'
' zyxwvutsrqponmlkjihgfedcba
' uvwxyz

Comentários

SeekOrigin é usado pelos Seek métodos de,,,, Stream BufferedStream FileStream MemoryStream BinaryWriter e outras classes.SeekOrigin is used by the Seek methods of Stream, BufferedStream, FileStream, MemoryStream, BinaryWriter, and other classes. Os Seek métodos usam um parâmetro offset relativo à posição especificada por SeekOrigin .The Seek methods take an offset parameter that is relative to the position specified by SeekOrigin.

Aplica-se a

Confira também