我有這個代碼，目前正在使用網絡瀏覽器。我怎樣才能將其轉換爲webclient？

Question

Private Sub WebBrowser1_DocumentCompleted_1(ByVal sender As System.Object, ByVal e As  System.Windows.Forms.WebBrowserDocumentCompletedEventArgs) Handles WebBrowser1.DocumentCompleted 
For Each Image As HtmlElement In WebBrowser1.Document.Images 
    If Image.GetAttribute("src").Contains("captcha") Then 
     Dim Web As New Net.WebClient 
     PictureBox1.Image = New Drawing.Bitmap(New IO.MemoryStream(Web.DownloadData(Image.GetAttribute("src")))) 
    End If 
Next 
End Sub 
End Class 

我試圖找到一種方法將此轉換爲webclient。由於

Answer 1

Dim webClient As New System.Net.WebClient 

Dim url As String = "yourPageURL" 
Dim htmlByte() As Byte = webClient.DownloadData(url) 

Dim htmlString As String 
htmlString = System.Text.Encoding.UTF8.GetString(htmlByte) 

' Generally using Regexes for Parsing HTML is not a good idea, this is just an example, you would use something like HTMLAgilityPack for parsing. 

' A quick and dirty hack that just make it work when html is minified 
htmlString = htmlString.Replace("<", System.Environment.NewLine + "<"); 

Dim matches As System.Text.RegularExpressions.MatchCollection 
Dim pattern As String = "<img.*?src\s*=\s*[""'](?<src>[^""']+)[""'].*?>" 
matches = System.Text.RegularExpressions.Regex.Matches(htmlString, pattern, System.Text.RegularExpressions.RegexOptions.IgnoreCase) 

For Each match As System.Text.RegularExpressions.Match In matches 
    If (Not match.Groups.Item("src").ToString().ToLower().Contains("captcha")) Then Continue For 

    PictureBox1.Image = New Drawing.Bitmap(New System.IO.MemoryStream(webClient.DownloadData(match.Groups.Item("src").ToString()))) 
Next