SeekOrigin 枚举
定义
指定流中的位置以供查找使用。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
- 继承
- 属性
字段
| Begin | 0 | 指定流的开始位置。Specifies the beginning of a stream. |
| Current | 1 | 指定流中的当前位置。Specifies the current position within a stream. |
| End | 2 | 指定流的结束位置。Specifies the end of a stream. |
示例
下面的示例演示如何从流的末尾开始向后读取,以及如何读取流中的指定点。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
注解
SeekOrigin 由、、、、 Seek Stream BufferedStream FileStream MemoryStream BinaryWriter 和其他类的方法使用。SeekOrigin is used by the Seek methods of Stream, BufferedStream, FileStream, MemoryStream, BinaryWriter, and other classes. Seek方法采用相对于指定的位置的 offset 参数 SeekOrigin 。The Seek methods take an offset parameter that is relative to the position specified by SeekOrigin.