Beginning .Net , C# Tips : Reading and writing a text file with a StreamReader in C# Programming

StreamReader and StreamWriter classes to write a string to a text file and then read the contents of that text file.

Here are Exmaple for Write and Read File.

C# Example :

         /////Write to a file
        System.IO.StreamWriter streamwriter = new System.IO.StreamWriter(System.IO.File.Open
(MapPath("TextFile.txt"),System.IO.FileMode.OpenOrCreate));
        streamwriter.Write("This is a sample string");
        streamwriter.Close();

        //////Read from a file
        System.IO.StreamReader reader =new System.IO.StreamReader(System.IO.File.Open(MapPath
("TextFile.txt"),System.IO.FileMode.Open));
        string tmp = reader.ReadToEnd();
        reader.Close();

When you create a StreamReader, you must pass an existing stream instance as a constructor
parameter. The reader uses this stream as its underlying data source.
In this sample, you use the File class’s Open method to open a writable FileStream for your StreamWriter.

Also notice that you no longer have to deal with byte arrays. The StreamReader takes care of converting the data to a type that’s more user-friendly than a byte array. In this example, you are using the ReadToEnd method to read the entire stream and convert it to a string.The StreamReader provides a number of different methods for reading data that you can use depending on exactly how you want to read the data, from reading a single character using the Read method, to reading the entire file using the ReadToEnd method.

VB.net Example :

    /////Write to a file
    Dim streamwriter As New System.IO.StreamWriter(System.IO.File.Open(MapPath
                     ("TextFile.txt"),System.IO.FileMode.Open))
    streamwriter.Write("This is a string")
    streamwriter.Close()

    //////Read from a file
    Dim reader As New System.IO.StreamReader(System.IO.File.Open(MapPath
                   ("TextFile.txt"),System.IO.FileMode.Open))
    Dim tmp As String = reader.ReadToEnd()
    reader.Close()

Beginning .Net , C# Tips : Write To a MemoryStream in C# Programming

There is a situation where you want to write data in Memory Stream.
You can write to the stream by encoding a string containing the information you want to write to a byte array and then using the stream’s Write method to write the byte array to the MemoryStreams.
The Close method also calls Flush internally to commit the data to the data store.

Here are sample Example
C# Example :

    byte[] data = System.Text.Encoding.ASCII.GetBytes("This is a sample string");
    System.IO.MemoryStream ms = new System.IO.MemoryStream();
    ms.Write(data, 0, data.Length);
    ms.Close();

VB.net Example :

    Dim data() As Byte = System.Text.Encoding.ASCII.GetBytes("This is a sample string")
    Dim ms As New System.IO.MemoryStream()
    ms.Write(data, 0, data.Length)
    ms.Close()