BinaryWriter 类
以二进制形式将基元类型写入流，并支持用特定的编码写入字符串。
**命名空间:**System.IO
**程序集:**mscorlib（在 mscorlib.dll 中）
语法
声明
<SerializableAttribute> _
<ComVisibleAttribute(True)> _
Public Class BinaryWriter
Implements IDisposable
用法
Dim instance As BinaryWriter
[SerializableAttribute]
[ComVisibleAttribute(true)]
public class BinaryWriter : IDisposable
[SerializableAttribute]
[ComVisibleAttribute(true)]
public ref class BinaryWriter : IDisposable
/** @attribute SerializableAttribute() */
/** @attribute ComVisibleAttribute(true) */
public class BinaryWriter implements IDisposable
SerializableAttribute
ComVisibleAttribute(true)
public class BinaryWriter implements IDisposable
备注
派生类可重写该类的方法，以提供唯一的字符编码。
下表列出了其他典型或相关的 I/O 任务的示例。
若要执行此操作... |
请参见本主题中的示例... |
|---|---|
创建文本文件。 |
|
写入文本文件。 |
|
读取文本文件。 |
|
读取二进制文件。 |
|
写入二进制文件。 |
示例
下面的代码示例阐释了如何在文件中存储应用程序设置以及如何检索这些设置。
Imports Microsoft.VisualBasic
Imports System
Imports System.IO
Imports System.Security.Permissions
Public Class Test
Shared Sub Main()
' Load application settings.
Dim appSettings As New AppSettings()
Console.WriteLine("App settings." & vbcrLf & "Aspect " & _
"Ratio: {0}, Lookup directory: {1}," & vbcrLf & "Auto " & _
"save time: {2} minutes, Show status bar: {3}" & vbCrLf, _
New Object(3){appSettings.AspectRatio.ToString(), _
appSettings.LookupDir, _
appSettings.AutoSaveTime.ToString(), _
appSettings.ShowStatusBar.ToString()})
' Change the settings.
appSettings.AspectRatio = 1.250
appSettings.LookupDir = "C:\Temp"
appSettings.AutoSaveTime = 10
appSettings.ShowStatusBar = True
' Save the new settings.
appSettings.Close()
End Sub
End Class
' Store and retrieve application settings.
Public Class AppSettings
Const fileName As String = "AppSettings#@@#.dat"
Dim aspRatio As Single
Dim lkupDir As String
Dim saveTime As Integer
Dim statusBar As Boolean
Property AspectRatio As Single
Get
Return aspRatio
End Get
Set
aspRatio = Value
End Set
End Property
Property LookupDir As String
Get
Return lkupDir
End Get
Set
lkupDir = Value
End Set
End Property
Property AutoSaveTime As Integer
Get
Return saveTime
End Get
Set
saveTime = Value
End Set
End Property
Property ShowStatusBar As Boolean
Get
Return statusBar
End Get
Set
statusBar = Value
End Set
End Property
Sub New()
' Create default application settings.
aspRatio = 1.3333
lkupDir = "C:\AppDirectory"
saveTime = 30
statusBar = False
If File.Exists(fileName) Then
Dim binReader As New BinaryReader( _
File.Open(fileName, FileMode.Open))
Try
' If the file is not empty,
' read the application settings.
If binReader.PeekChar() <> -1 Then
aspRatio = binReader.ReadSingle()
lkupDir = binReader.ReadString()
saveTime = binReader.ReadInt32()
statusBar = binReader.ReadBoolean()
Return
End If
' If the end of the stream is reached before reading
' the four data values, ignore the error and use the
' default settings for the remaining values.
Catch ex As EndOfStreamException
Console.WriteLine("{0} caught and ignored. " & _
"Using default values.", ex.GetType().Name)
Finally
binReader.Close()
End Try
End If
End Sub
' Create a file and store the application settings.
Sub Close()
Dim binWriter As New BinaryWriter( _
File.Open(fileName, FileMode.Create))
Try
binWriter.Write(aspRatio)
binWriter.Write(lkupDir)
binWriter.Write(saveTime)
binWriter.Write(statusBar)
Finally
binWriter.Close()
End Try
End Sub
End Class
using System;
using System.IO;
using System.Security.Permissions;
class Test
{
static void Main()
{
// Load application settings.
AppSettings appSettings = new AppSettings();
Console.WriteLine("App settings.\nAspect Ratio: {0}, " +
"Lookup directory: {1},\nAuto save time: {2} minutes, " +
"Show status bar: {3}\n",
new Object[4]{appSettings.AspectRatio.ToString(),
appSettings.LookupDir, appSettings.AutoSaveTime.ToString(),
appSettings.ShowStatusBar.ToString()});
// Change the settings.
appSettings.AspectRatio = 1.250F;
appSettings.LookupDir = @"C:\Temp";
appSettings.AutoSaveTime = 10;
appSettings.ShowStatusBar = true;
// Save the new settings.
appSettings.Close();
}
}
// Store and retrieve application settings.
class AppSettings
{
const string fileName = "AppSettings#@@#.dat";
float aspectRatio;
string lookupDir;
int autoSaveTime;
bool showStatusBar;
public float AspectRatio
{
get{ return aspectRatio; }
set{ aspectRatio = value; }
}
public string LookupDir
{
get{ return lookupDir; }
set{ lookupDir = value; }
}
public int AutoSaveTime
{
get{ return autoSaveTime; }
set{ autoSaveTime = value; }
}
public bool ShowStatusBar
{
get{ return showStatusBar; }
set{ showStatusBar = value; }
}
public AppSettings()
{
// Create default application settings.
aspectRatio = 1.3333F;
lookupDir = @"C:\AppDirectory";
autoSaveTime = 30;
showStatusBar = false;
if(File.Exists(fileName))
{
BinaryReader binReader =
new BinaryReader(File.Open(fileName, FileMode.Open));
try
{
// If the file is not empty,
// read the application settings.
if(binReader.PeekChar() != -1)
{
aspectRatio = binReader.ReadSingle();
lookupDir = binReader.ReadString();
autoSaveTime = binReader.ReadInt32();
showStatusBar = binReader.ReadBoolean();
}
}
// If the end of the stream is reached before reading
// the four data values, ignore the error and use the
// default settings for the remaining values.
catch(EndOfStreamException e)
{
Console.WriteLine("{0} caught and ignored. " +
"Using default values.", e.GetType().Name);
}
finally
{
binReader.Close();
}
}
}
// Create a file and store the application settings.
public void Close()
{
using(BinaryWriter binWriter =
new BinaryWriter(File.Open(fileName, FileMode.Create)))
{
binWriter.Write(aspectRatio);
binWriter.Write(lookupDir);
binWriter.Write(autoSaveTime);
binWriter.Write(showStatusBar);
}
}
}
using namespace System;
using namespace System::IO;
using namespace System::Security::Permissions;
// Store and retrieve application settings.
ref class AppSettings
{
private:
static String^ fileName = "AppSettings#@@#.dat";
float aspectRatio;
String^ lookupDir;
int autoSaveTime;
Boolean showStatusBar;
public:
property float AspectRatio
{
float get()
{
return aspectRatio;
}
void set( float value )
{
aspectRatio = value;
}
}
property String^ LookupDir
{
String^ get()
{
return lookupDir;
}
void set( String^ value )
{
lookupDir = value;
}
}
property int AutoSaveTime
{
int get()
{
return autoSaveTime;
}
void set( int value )
{
autoSaveTime = value;
}
}
property Boolean ShowStatusBar
{
Boolean get()
{
return showStatusBar;
}
void set( Boolean value )
{
showStatusBar = value;
}
}
AppSettings()
{
// Create default application settings.
aspectRatio = 1.3333F;
lookupDir = "C:\\AppDirectory";
autoSaveTime = 30;
showStatusBar = false;
if ( File::Exists( fileName ) )
{
BinaryReader^ binReader = gcnew BinaryReader( File::Open( fileName, FileMode::Open ) );
try
{
// If the file is not empty,
// read the application settings.
if ( binReader->PeekChar() != -1 )
{
aspectRatio = binReader->ReadSingle();
lookupDir = binReader->ReadString();
autoSaveTime = binReader->ReadInt32();
showStatusBar = binReader->ReadBoolean();
return;
}
}
// If the end of the stream is reached before reading
// the four data values, ignore the error and use the
// default settings for the remaining values.
catch ( EndOfStreamException^ e )
{
Console::WriteLine( "{0} caught and ignored. "
"Using default values.", e->GetType()->Name );
}
finally
{
binReader->Close();
}
}
}
// Create a file and store the application settings.
void Close()
{
BinaryWriter^ binWriter = gcnew BinaryWriter( File::Open( fileName, FileMode::Create ) );
try
{
binWriter->Write( aspectRatio );
binWriter->Write( lookupDir );
binWriter->Write( autoSaveTime );
binWriter->Write( showStatusBar );
}
finally
{
binWriter->Close();
}
}
};
int main()
{
// Load application settings.
AppSettings^ appSettings = gcnew AppSettings;
array<Object^>^someObject = {appSettings->AspectRatio.ToString(),appSettings->LookupDir,appSettings->AutoSaveTime.ToString(),appSettings->ShowStatusBar.ToString()};
Console::WriteLine( "App settings.\nAspect Ratio: {0}, "
"Lookup directory: {1},\nAuto save time: {2} minutes, "
"Show status bar: {3}\n", someObject );
// Change the settings.
appSettings->AspectRatio = 1.250F;
appSettings->LookupDir = "C:\\Temp";
appSettings->AutoSaveTime = 10;
appSettings->ShowStatusBar = true;
// Save the new settings.
appSettings->Close();
}
import System.*;
import System.IO.*;
import System.Security.Permissions.*;
class Test
{
public static void main(String[] args)
{
// Load application settings.
AppSettings appSettings = new AppSettings();
Console.WriteLine("App settings.\nAspect Ratio: {0}, "
+ "Lookup directory: {1},\nAuto save time: {2} minutes, "
+ "Show status bar: {3}\n",
new Object[]{System.Convert.ToString(appSettings.get_AspectRatio()),
appSettings.get_LookupDir(),
System.Convert.ToString(appSettings.get_AutoSaveTime()),
System.Convert.ToString(appSettings.get_ShowStatusBar())});
// Change the settings.
appSettings.set_AspectRatio(1.25F);
appSettings.set_LookupDir("C:\\Temp");
appSettings.set_AutoSaveTime ( 10);
appSettings.set_ShowStatusBar( true);
// Save the new settings.
appSettings.Close();
} //main
} //Test
// Store and retrieve application settings.
class AppSettings
{
private String fileName = "AppSettings#@@#.dat";
private float aspectRatio;
private String lookupDir;
private int autoSaveTime;
private boolean showStatusBar;
/** @property
*/
public float get_AspectRatio()
{
return aspectRatio ;
}//get_AspectRatio
/** @property
*/
public void set_AspectRatio ( float value )
{
aspectRatio = value;
}//set_AspectRatio
/** @property
*/
public String get_LookupDir()
{
return lookupDir ;
}//get_LookupDir
/** @property
*/
public void set_LookupDir ( String value )
{
lookupDir = value;
}//set_LookupDir
/** @property
*/
public int get_AutoSaveTime()
{
return autoSaveTime ;
}//get_AutoSaveTime
/** @property
*/
public void set_AutoSaveTime ( int value )
{
autoSaveTime = value;
}//set_AutoSaveTime
/** @property
*/
public boolean get_ShowStatusBar()
{
return showStatusBar ;
}//get_ShowStatusBar
/** @property
*/
public void set_ShowStatusBar ( boolean value )
{
showStatusBar = value;
}//set_ShowStatusBar
public AppSettings()
{
// Create default application settings.
aspectRatio = 1.3333F;
lookupDir = "C:\\AppDirectory";
autoSaveTime = 30;
showStatusBar = false;
if ( File.Exists(fileName) ) {
BinaryReader binReader =
new BinaryReader(File.Open(fileName, FileMode.Open));
try {
// If the file is not empty,
// read the application settings.
if ( binReader.PeekChar() !=-1 ) {
aspectRatio = binReader.ReadSingle();
lookupDir = binReader.ReadString();
autoSaveTime = binReader.ReadInt32();
showStatusBar = binReader.ReadBoolean();
}
}
// If the end of the stream is reached before reading
// the four data values, ignore the error and use the
// default settings for the remaining values.
catch(EndOfStreamException e) {
Console.WriteLine("{0} caught and ignored. "
+ "Using default values.", e.GetType().get_Name());
}
finally {
binReader.Close();
}
}
} //AppSettings
// Create a file and store the application settings.
public void Close()
{
BinaryWriter binWriter =
new BinaryWriter(File.Open(fileName, FileMode.Create));
try {
binWriter.Write(aspectRatio);
binWriter.Write(lookupDir);
binWriter.Write(autoSaveTime);
binWriter.Write(showStatusBar);
}
finally {
if ( binWriter != null ) {
binWriter= null;
}
}
} //Close
} //AppSettings
继承层次结构
System.Object
System.IO.BinaryWriter
线程安全
此类型的任何公共静态（Visual Basic 中的 Shared）成员都是线程安全的，但不保证所有实例成员都是线程安全的。
平台
Windows 98、Windows 2000 SP4、Windows CE、Windows Millennium Edition、Windows Mobile for Pocket PC、Windows Mobile for Smartphone、Windows Server 2003、Windows XP Media Center Edition、Windows XP Professional x64 Edition、Windows XP SP2、Windows XP Starter Edition
.NET Framework 并不是对每个平台的所有版本都提供支持。有关受支持版本的列表，请参见系统要求。
版本信息
.NET Framework
受以下版本支持：2.0、1.1、1.0
.NET Compact Framework
受以下版本支持：2.0、1.0
请参见
参考
BinaryWriter 成员
System.IO 命名空间
Encoding