File.OpenText(String) File.OpenText(String) File.OpenText(String) File.OpenText(String) Method

Definition

Opens an existing UTF-8 encoded text file for reading.

public:
 static System::IO::StreamReader ^ OpenText(System::String ^ path);
public static System.IO.StreamReader OpenText (string path);
static member OpenText : string -> System.IO.StreamReader
Public Shared Function OpenText (path As String) As StreamReader

Parameters

path
String String String String

The file to be opened for reading.

Returns

Exceptions

path is a zero-length string, contains only white space, or contains one or more invalid characters as defined by InvalidPathChars.

The specified path, file name, or both exceed the system-defined maximum length.

The specified path is invalid, (for example, it is on an unmapped drive).

Examples

The following example opens a text file for reading.

using namespace System;
using namespace System::IO;
using namespace System::Text;
int main()
{
   String^ path = "c:\\temp\\MyTest.txt";
   
   if ( !File::Exists( path ) )
   {
      // Create the file.
      FileStream^ fs = File::Create( path );
      try
      {
         array<Byte>^info = (gcnew UTF8Encoding( true ))->GetBytes( "This is some text in the file." );
         
         // Add some information to the file.
         fs->Write( info, 0, info->Length );
      }
      finally
      {
         if ( fs )
            delete (IDisposable^)fs;
      }
   }
   
   // Open the stream and read it back.
   StreamReader^ sr = File::OpenText( path );
   try
   {
      String^ s = "";
      while ( s = sr->ReadLine() )
      {
         Console::WriteLine( s );
      }
   }
   finally
   {
      if ( sr )
         delete (IDisposable^)sr;
   }
}
using System;
using System.IO;
using System.Text;

class Test 
{
    public static void Main() 
    {
        string path = @"c:\temp\MyTest.txt";

        if (!File.Exists(path)) 
        {
            // Create the file.
            using (FileStream fs = File.Create(path)) 
            {
                Byte[] info = 
                    new UTF8Encoding(true).GetBytes("This is some text in the file.");

                // Add some information to the file.
                fs.Write(info, 0, info.Length);
            }
        }

        // Open the stream and read it back.
        using (StreamReader sr = File.OpenText(path)) 
        {
            string s = "";
            while ((s = sr.ReadLine()) != null) 
            {
                Console.WriteLine(s);
            }
        }
    }
}
Imports System.IO
Imports System.Text

Public Class Test
  Public Shared Sub Main()
    Dim path As String = "c:\temp\MyTest.txt"

    If Not File.Exists(path) Then
      ' Create the file.
      Using fs As FileStream = File.Create(path)
        Dim info As Byte() = _
         New UTF8Encoding(True).GetBytes("This is some text in the file.")

        ' Add some information to the file.
        fs.Write(info, 0, info.Length)
      End Using
    End If

    ' Open the stream and read it back. 
    Using sr As StreamReader = File.OpenText(path)
      Do While sr.Peek() >= 0
        Console.WriteLine(sr.ReadLine())
      Loop
    End Using

  End Sub
End Class

Remarks

This method is equivalent to the StreamReader(String) constructor overload.

The path parameter is permitted to specify relative or absolute path information. Relative path information is interpreted as relative to the current working directory. To obtain the current working directory, see GetCurrentDirectory.

For a list of common I/O tasks, see Common I/O Tasks.

Security

FileIOPermission
for reading from the specified file. Associated enumeration: Read

Applies to

See also