FileInfo.AppendText Metoda

Reference

Definice

Obor názvů:: System.IO

Sestavení:: mscorlib.dll, System.IO.FileSystem.dll

Sestavení:: System.IO.FileSystem.dll

Sestavení:: System.Runtime.dll

Sestavení:: mscorlib.dll

Sestavení:: netstandard.dll

Zdroj:: FileInfo.cs

Zdroj:: FileInfo.cs

Zdroj:: FileInfo.cs

Důležité

Některé informace platí pro předběžně vydaný produkt, který se může zásadně změnit, než ho výrobce nebo autor vydá. Microsoft neposkytuje žádné záruky, výslovné ani předpokládané, týkající se zde uváděných informací.

Vytvoří StreamWriter text, který připojí text k souboru reprezentované touto instancí objektu FileInfo.

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

public System.IO.StreamWriter AppendText ();

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

Public Function AppendText () As StreamWriter

Návraty

StreamWriter

Nový StreamWriter.

Příklady

Následující příklad přidá text do souboru a přečte ze souboru.

using namespace System;
using namespace System::IO;

int main()
{
   FileInfo^ fi = gcnew FileInfo( "c:\\MyTest.txt" );
   
   // This text is added only once to the file.
   if (  !fi->Exists )
   {
      //Create a file to write to.
      StreamWriter^ sw = fi->CreateText();
      try
      {
         sw->WriteLine( "Hello" );
         sw->WriteLine( "And" );
         sw->WriteLine( "Welcome" );
      }
      finally
      {
         if ( sw )
            delete (IDisposable^)sw;
      }
   }
   
   // This text will always be added, making the file longer over time
   // if it is not deleted.
   StreamWriter^ sw = fi->AppendText();
   try
   {
      sw->WriteLine( "This" );
      sw->WriteLine( "is Extra" );
      sw->WriteLine( "Text" );
   }
   finally
   {
      if ( sw )
         delete (IDisposable^)sw;
   }
   
   //Open the file to read from.
   StreamReader^ sr = fi->OpenText();
   try
   {
      String^ s = "";
      while ( s = sr->ReadLine() )
      {
         Console::WriteLine( s );
      }
   }
   finally
   {
      if ( sr )
         delete (IDisposable^)sr;
   }
}
//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

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

Následující příklad ukazuje přidání textu na konec souboru a také zobrazí výsledek operace připojení do konzoly. Při prvním volání této rutiny se soubor vytvoří, pokud neexistuje. Poté se zadaný text připojí k souboru.

using namespace System;
using namespace System::IO;
int main()
{

   FileInfo^ fi = gcnew 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 = gcnew 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...

}

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...

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FileInfo.AppendText Metoda

Definice

Návraty

Příklady

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