.NET Reference Guide > WebClient

InformIT: .NET Reference Guide - WebClient - Getting a Page the Easy Way

1.)

Imports System.IO
Imports System.NET

Sub getPage()
  ’ Create a WebClient instance
  Dim myClient As New WebClient()
  ’ Open the page and get the response as a stream
  Dim response As Stream = myClient.OpenRead("http://blog.mischel.com")
  ’ read the response into a string and show the result
  Dim sr As New StreamReader(response)
  Dim s As String = sr.ReadToEnd()
  Console.WriteLine(s)
  sr.Close()
  response.Close()
End Sub

2.)

Sub getImage()
  ’ Create a WebClient instance
  Dim myClient As New WebClient()
  ’ Open the page and get the response into a byte buffer
  Dim buffer As Byte() = myClient.DownloadData("http://www.mischel.com/diary/2002/09/charlie9.jpg")
  ’ Open a file and output the data
  Dim fs As New FileStream("charlie9.jpg", FileMode.Create)
  fs.Write(buffer, 0, buffer.Length)
  fs.Close()
End Sub

3.)

Sub getBigFile()
  ’ Create a WebClient instance
  Dim myClient As New WebClient()
  ’ Open a stream that references the page
  Dim response As Stream = myClient.OpenRead("http://www.mischel.com/diary/2002/09/charlie9.jpg")
  Dim fs As New FileStream("charlie9.jpg", FileMode.Create)
  Dim buffer(1024) As Byte
  Dim bytesRead As Integer = -1
  While (bytesRead <> 0)
    bytesRead = response.Read(buffer, 0, buffer.Length)
    Console.WriteLine("{0} bytes read", bytesRead)
    If (bytesRead > 0) Then
      fs.Write(buffer, 0, bytesRead)
    End If
  End While
  fs.Close()
  response.Close()
End Sub

4.)

client.Headers.Add ("user-agent", "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.2; .NET CLR 1.0.3705;)")

5.)

X-Pingback = http://blog.mischel.com/xmlrpc.php
Keep-Alive = timeout=5, max=150
Connection = Keep-Alive
Transfer-Encoding = chunked
Content-Type = text/html; charset=UTF-8
Date = Tue, 06 Mar 2007 17:04:07 GMT
Server = Apache Webserver
X-Powered-By = PHP/4.4.4

6.)

’ show the response headers
Dim headers As WebHeaderCollection = myClient.ResponseHeaders
Console.WriteLine("Response headers:")
Dim i As Integer
For i = 0 To headers.Count - 1
  Console.WriteLine("{0} = {1}", headers.GetKey(i), headers.Get(i))
Next