BinaryReader.ReadBoolean Metod
Definition
Viktigt
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Läser ett Boolean värde från den aktuella strömmen och för fram strömmens aktuella position med en byte.
public:
virtual bool ReadBoolean();
public virtual bool ReadBoolean();
abstract member ReadBoolean : unit -> bool
override this.ReadBoolean : unit -> bool
Public Overridable Function ReadBoolean () As Boolean
Returer
trueom bytet inte är noll. annars . false
Undantag
Strömmens slut nås.
Strömmen är stängd.
Ett I/O-fel uppstod.
Exempel
Följande kodexempel visar hur du lagrar och hämtar programinställningar i en fil.
using System;
using System.IO;
using System.Text;
class ConsoleApplication
{
const string fileName = "AppSettings.dat";
static void Main()
{
WriteDefaultValues();
DisplayValues();
}
public static void WriteDefaultValues()
{
using (var stream = File.Open(fileName, FileMode.Create))
{
using (var writer = new BinaryWriter(stream, Encoding.UTF8, false))
{
writer.Write(1.250F);
writer.Write(@"c:\Temp");
writer.Write(10);
writer.Write(true);
}
}
}
public static void DisplayValues()
{
float aspectRatio;
string tempDirectory;
int autoSaveTime;
bool showStatusBar;
if (File.Exists(fileName))
{
using (var stream = File.Open(fileName, FileMode.Open))
{
using (var reader = new BinaryReader(stream, Encoding.UTF8, false))
{
aspectRatio = reader.ReadSingle();
tempDirectory = reader.ReadString();
autoSaveTime = reader.ReadInt32();
showStatusBar = reader.ReadBoolean();
}
}
Console.WriteLine("Aspect ratio set to: " + aspectRatio);
Console.WriteLine("Temp directory is: " + tempDirectory);
Console.WriteLine("Auto save time set to: " + autoSaveTime);
Console.WriteLine("Show status bar: " + showStatusBar);
}
}
}
open System.IO
open System.Text
let fileName = "AppSettings.dat"
let writeDefaultValues () =
use stream = File.Open(fileName, FileMode.Create)
use writer = new BinaryWriter(stream, Encoding.UTF8, false)
writer.Write 1.250F
writer.Write @"c:\Temp"
writer.Write 10
writer.Write true
let displayValues () =
if File.Exists fileName then
use stream = File.Open(fileName, FileMode.Open)
use reader = new BinaryReader(stream, Encoding.UTF8, false)
let aspectRatio = reader.ReadSingle()
let tempDirectory = reader.ReadString()
let autoSaveTime = reader.ReadInt32()
let showStatusBar = reader.ReadBoolean()
printfn $"Aspect ratio set to: {aspectRatio}"
printfn $"Temp directory is: {tempDirectory}"
printfn $"Auto save time set to: {autoSaveTime}"
printfn $"Show status bar: {showStatusBar}"
writeDefaultValues ()
displayValues ()
Imports System.IO
Module Module1
Const fileName As String = "AppSettings.dat"
Sub Main()
WriteDefaultValues()
DisplayValues()
End Sub
Sub WriteDefaultValues()
Using writer As BinaryWriter = New BinaryWriter(File.Open(fileName, FileMode.Create))
writer.Write(1.25F)
writer.Write("c:\Temp")
writer.Write(10)
writer.Write(True)
End Using
End Sub
Sub DisplayValues()
Dim aspectRatio As Single
Dim tempDirectory As String
Dim autoSaveTime As Integer
Dim showStatusBar As Boolean
If (File.Exists(fileName)) Then
Using reader As BinaryReader = New BinaryReader(File.Open(fileName, FileMode.Open))
aspectRatio = reader.ReadSingle()
tempDirectory = reader.ReadString()
autoSaveTime = reader.ReadInt32()
showStatusBar = reader.ReadBoolean()
End Using
Console.WriteLine("Aspect ratio set to: " & aspectRatio)
Console.WriteLine("Temp directory is: " & tempDirectory)
Console.WriteLine("Auto save time set to: " & autoSaveTime)
Console.WriteLine("Show status bar: " & showStatusBar)
End If
End Sub
End Module
Kommentarer
BinaryReader återställer inte filpositionen efter en misslyckad läsning.
En lista över vanliga I/O-uppgifter finns i Vanliga I/O-uppgifter.