ReadByte Method

FileStream.ReadByte Method ()

 

Reads a byte from the file and advances the read position one byte.

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

public override int ReadByte()

Return Value

Type: System.Int32

The byte, cast to an Int32, or -1 if the end of the stream has been reached.

Exception Condition
NotSupportedException

The current stream does not support reading.

ObjectDisposedException

The current stream is closed.

This method overrides ReadByte.

System_CAPS_noteNote

Use the CanRead property to determine whether the current instance supports reading. For additional information, see CanRead.

Notes to Implementers:

The default implementation on Stream creates a new single-byte array and then calls Read. While this is formally correct, it is inefficient. Any stream with an internal buffer should override this method and provide a much more efficient version that reads the buffer directly, avoiding the extra array allocation on every call.

For a list of common file and directory operations, see Common I/O Tasks.

The following code example shows how to write data to a file, byte by byte, and then verify that the data was written correctly.

using System;
using System.IO;

class FStream
{
    static void Main()
    {
        const string fileName = "Test#@@#.dat";

        // Create random data to write to the file.
        byte[] dataArray = new byte[100000];
        new Random().NextBytes(dataArray);

        using(FileStream  
            fileStream = new FileStream(fileName, FileMode.Create))
        {
            // Write the data to the file, byte by byte.
            for(int i = 0; i < dataArray.Length; i++)
            {
                fileStream.WriteByte(dataArray[i]);
            }

            // Set the stream position to the beginning of the file.
            fileStream.Seek(0, SeekOrigin.Begin);

            // Read and verify the data.
            for(int i = 0; i < fileStream.Length; i++)
            {
                if(dataArray[i] != fileStream.ReadByte())
                {
                    Console.WriteLine("Error writing data.");
                    return;
                }
            }
            Console.WriteLine("The data was written to {0} " +
                "and verified.", fileStream.Name);
        }
    }
}

Universal Windows Platform
Available since 10
.NET Framework
Available since 1.1
Silverlight
Available since 2.0
Windows Phone Silverlight
Available since 7.0
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