FileInfo.AppendText Methode

public:
 System::IO::StreamWriter ^ AppendText();

public System.IO.StreamWriter AppendText();

member this.AppendText : unit -> System.IO.StreamWriter

Public Function AppendText () As StreamWriter

Retouren

Een nieuwe StreamWriter.

Voorbeelden

In het volgende voorbeeld wordt tekst toegevoegd aan een bestand en wordt gelezen uit het bestand.

using System;
using System.IO;

class Test
{
    
    public static void Main()
    {
        FileInfo fi = new FileInfo(@"c:\MyTest.txt");

        // This text is added only once to the file.
        if (!fi.Exists)
        {
            //Create a file to write to.
            using (StreamWriter sw = fi.CreateText())
            {
                sw.WriteLine("Hello");
                sw.WriteLine("And");
                sw.WriteLine("Welcome");
            }	
        }

        // This text will always be added, making the file longer over time
        // if it is not deleted.
        using (StreamWriter sw = fi.AppendText())
        {
            sw.WriteLine("This");
            sw.WriteLine("is Extra");
            sw.WriteLine("Text");
        }	

        //Open the file to read from.
        using (StreamReader sr = fi.OpenText())
        {
            string s = "";
            while ((s = sr.ReadLine()) != null)
            {
                Console.WriteLine(s);
            }
        }
    }
}
//This code produces output similar to the following;
//results may vary based on the computer/file structure/etc.:
//
//Hello
//And
//Welcome
//This
//is Extra
//Text

//When you run this application a second time, you will see the following output:
//
//Hello
//And
//Welcome
//This
//is Extra
//Text
//This
//is Extra
//Text

Imports System.IO

Public Class Test

    Public Shared Sub Main()
        Dim fi As FileInfo = New FileInfo("c:\temp\MyTest.txt")
        Dim sw As StreamWriter

        ' This text is added only once to the file.
        If fi.Exists = False Then
            'Create a file to write to.
            sw = fi.CreateText()
            sw.WriteLine("Hello")
            sw.WriteLine("And")
            sw.WriteLine("Welcome")
            sw.Flush()
            sw.Close()
        End If

        ' This text will always be added, making the file longer over time
        ' if it is not deleted.
        sw = fi.AppendText()

        sw.WriteLine("This")
        sw.WriteLine("is Extra")
        sw.WriteLine("Text")
        sw.Flush()
        sw.Close()

        'Open the file to read from.
        Dim sr As StreamReader = fi.OpenText()
        Dim s As String
        Do While sr.Peek() >= 0
            s = sr.ReadLine()
            Console.WriteLine(s)
        Loop
        sr.Close()
    End Sub
End Class
'This code produces output similar to the following; 
'results may vary based on the computer/file structure/etc.:
'
'Hello
'And
'Welcome
'This
'is Extra
'Text

'When you run this application a second time, you will see the following output:
'
'Hello
'And
'Welcome
'This
'is Extra
'Text
'This
'is Extra
'Text

In het volgende voorbeeld ziet u hoe u tekst toevoegt aan het einde van een bestand en ook het resultaat van de toevoegbewerking aan de console weergeeft. De eerste keer dat deze routine wordt aangeroepen, wordt het bestand gemaakt als het niet bestaat. Daarna wordt de opgegeven tekst toegevoegd aan het bestand.

using System;
using System.IO;

public class AppendTextTest
{
    public static void Main()
    {
        FileInfo fi = new FileInfo("temp.txt");
        // Create a writer, ready to add entries to the file.
        StreamWriter sw = fi.AppendText();
        sw.WriteLine("Add as many lines as you like...");
        sw.WriteLine("Add another line to the output...");
        sw.Flush();
        sw.Close();
        // Get the information out of the file and display it.
        // Remember that the file might have other lines if it already existed.
        StreamReader sr = new StreamReader(fi.OpenRead());
        while (sr.Peek() != -1)
            Console.WriteLine( sr.ReadLine() );
    }
}
//This code produces output similar to the following;
//results may vary based on the computer/file structure/etc.:
//Add as many lines as you like...
//Add another line to the output...

Imports System.IO

Public Class AppendTextTest
    Public Shared Sub Main()
        Dim fi As New FileInfo("temp.txt")
        Dim sw As StreamWriter = fi.AppendText()
        sw.WriteLine("Add as many lines as you like...")
        sw.WriteLine("Add another line to the output...")
        sw.Flush()
        sw.Close()
        Dim sr As New StreamReader(fi.OpenRead())
        ' Get the information out of the file and display it.
        ' Remember that the file might have other lines if it already existed.
        While sr.Peek() <> -1
            Console.WriteLine(sr.ReadLine())
        End While
    End Sub
End Class
'This code produces output similar to the following;
'results may vary based on the computer/file structure/etc.:
'Add as many lines as you like...
'Add another line to the output...

Zie ook

• StreamWriter
• Bestands- en Stream-I/O
• Procedure: Tekst uit een bestand lezen
• Procedure: Tekst naar een bestand schrijven
• Procedure: lezen en schrijven naar een nieuw gegevensbestand