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FileInfo.OpenText Method

.NET Framework 4

Other Versions

Creates a StreamReader with UTF8 encoding that reads from an existing text file.

Namespace: System.IO
Assembly: mscorlib (in mscorlib.dll)

Syntax

C++

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public StreamReader OpenText()

Return Value

Type: System.IO.StreamReader
A new StreamReader with UTF8 encoding.

Exceptions

Exception	Condition
SecurityException	The caller does not have the required permission.
FileNotFoundException	The file is not found.
UnauthorizedAccessException	path is read-only or is a directory.
DirectoryNotFoundException	The specified path is invalid, such as being on an unmapped drive.

Examples

The following example reads text from a file.

C++

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using System;
using System.IO;
using System.Text;

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

        FileInfo fi = new FileInfo(path);

        // Check for existing file
        if (!fi.Exists)
        {
            // Create the file.
            using (FileStream fs = fi.Create())
            {
                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);
                fs.Close();
            }
        }

        // Open the stream and read it back.
        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.:
//
//This is some text in the file.
//

Version Information

.NET Framework

Supported in: 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

.NET Framework Security

FileIOPermission
for reading and writing files. Associated enumerations: FileIOPermissionAccess.Read, FileIOPermissionAccess.Write

Platforms

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.