System.ArgumentException：'路径中的非法字符。没有的地方

Question

据称存在非法字符，而没有非法字符。我的实例让我发疯。问题发生在Dim datastream As Stream = client.OpenRead(url)。

第一个Dim url As String = GoogleSearch & MovieName不想接受HTML格式作为字符串。好。我从字符串中删除了https://，现在它只是'www .____`格式，仍然可以与webclient一起使用。现在，它把这个拉到我身上。为什么？在Visual Studio外部测试时，它可以工作。

我的输入字符串URL是：www.google.com/search?q=imdb+Orville，这会导致网络客户端出现此错误：

  

System.ArgumentException：“路径中包含非法字符。”

Public Class Form1
    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load()

    End Sub

    Public Property status As Boolean
    Public Property Id As String
    Public Property ImdbURL As String

    Private GoogleSearch As String = "www.google.com/search?q=imdb+"
    Private BingSearch As String = "www.bing.com/search?q=imdb+"
    Private AskSearch As String = "www.ask.com/web?q=imdb+"

    Private Function match(ByVal regex As String, ByVal html As String, ByVal Optional i As Integer = 1) As String
        Return New Regex(regex, RegexOptions.Multiline).Match(html).Groups(i).Value.Trim()
    End Function

    Private Function matchAll(ByVal regex As String, ByVal html As String, ByVal Optional i As Integer = 1) As ArrayList
        Dim list As ArrayList = New ArrayList()

        For Each m As Match In New Regex(regex, RegexOptions.Multiline).Matches(html)
            list.Add(m.Groups(i).Value.Trim())
        Next

        Return list

    End Function

    Private Function getIMDbUrl(ByVal MovieName As String, ByVal Optional searchEngine As String = "google") As String
        Dim url As String = GoogleSearch & MovieName
        If searchEngine.ToLower().Equals("bing") Then url = BingSearch & MovieName
        If searchEngine.ToLower().Equals("ask") Then url = AskSearch & MovieName
        Dim html As String = getUrlData(url)
        Dim imdbUrls As ArrayList = matchAll("<a href=""(http://www.imdb.com/title/tt\d{7}/)"".*?>.*?</a>", html)

        If imdbUrls.Count > 0 Then
            Return CStr(imdbUrls(0))
        ElseIf searchEngine.ToLower().Equals("google") Then
            Return getIMDbUrl(MovieName, "bing")
        ElseIf searchEngine.ToLower().Equals("bing") Then
            Return getIMDbUrl(MovieName, "ask")
        Else
            Return String.Empty
        End If

    End Function

    Private Function getUrlData(ByVal url As String) As String
        Dim client As WebClient = New WebClient()
        Dim r As Random = New Random()
        client.Headers("X-Forwarded-For") = r.[Next](0, 255) & "." & r.[Next](0, 255) & "." & r.[Next](0, 255) & "." & r.[Next](0, 255)
        client.Headers("User-Agent") = "Mozilla/" & r.[Next](3, 5) & ".0 (Windows NT " & r.[Next](3, 5) & "." & r.[Next](0, 2) & "; rv:2.0.1) Gecko/20100101 Firefox/" & r.[Next](3, 5) & "." & r.[Next](0, 5) & "." & r.[Next](0, 5)
        Dim datastream As Stream = client.OpenRead(url)
        Dim reader As StreamReader = New StreamReader(datastream)
        Dim sb As StringBuilder = New StringBuilder()

        While Not reader.EndOfStream
            sb.Append(reader.ReadLine())
        End While

        Return sb.ToString()

    End Function

    Private Sub parseIMDbPage(ByVal imdbUrl As String)
        Dim html As String = getUrlData(imdbUrl)
        Id = match("<link rel=""canonical"" href=""http://www.imdb.com/title/(tt\d{7})/"" />", html)

        If Not String.IsNullOrEmpty(Id) Then
            status = True
            imdbUrl = "http://www.imdb.com/title/" & Id & "/"
        End If

    End Sub

    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
        Dim TextFromBox As String = RichTextBox1.Text
        Dim imdbUrl As String = getIMDbUrl(TextFromBox)
        parseIMDbPage(imdbUrl)
        MessageBox.Show(Id)

    End Sub

End Class