问题描述
尝试使用vb.net表单应用程序自动登录到网站。我没有收到任何例外或错误。我导航到我的页面，设置电子邮件和密码属性，然后单击网页上的“ cmd”按钮。我已经使用Debug语句验证了属性已设置。
点击网页上的“ cmd”按钮后，我回到了最初的页面，找不到任何告诉我有异常或错误的信息。
我能够使用相同的电子邮件/密码组合使用chrome或IE登录网页。
这是我的代码。
Private mPageReady As Boolean = False
Private Sub Form1_Load(sender As Object,e As EventArgs) Handles Me.Load
AddHandler Me.Webbrowser1.DocumentCompleted,New WebbrowserDocumentCompletedEventHandler(AddressOf PageWaiter)
End Sub
Public Function LoginUser(pEmailAddress As String,pPassword As String) As Boolean
Dim IsOkay As Boolean = False
Dim myURL As String = "https://login.wlpc.com/index.PHP/"
Me.Webbrowser1.Navigate(myURL)
WaitForPageLoad()
Debug.WriteLine("After Navigate: " & Me.Webbrowser1.DocumentText)
Try
Me.Webbrowser1.Document.GetElementById("email").SetAttribute("value",pEmailAddress)
Debug.WriteLine("After assignment of email: " & Me.Webbrowser1.Document.GetElementById("email").GetAttribute("value"))
Me.Webbrowser1.Document.GetElementById("password").SetAttribute("value",pPassword)
Debug.WriteLine("After assignment of password: " & Me.Webbrowser1.Document.GetElementById("password").GetAttribute("value"))
Dim myDoc As HtmlDocument = Me.Webbrowser1.Document
Dim myCmd As HtmlElement = myDoc.All("cmd")
myCmd.InvokeMember("click")
WaitForPageLoad()
Debug.WriteLine("After click: " & Me.Webbrowser1.DocumentText)
IsOkay = True
Catch ex As Exception
IsOkay = False
End Try
Return IsOkay
End Function
Public Function GetPage(URL As String) As String
Debug.WriteLine(String.Format("Accessing {0}",URL))
Me.Webbrowser1.Navigate(URL)
WaitForPageLoad()
Dim pagedata As String = Me.Webbrowser1.DocumentText
Return pagedata
End Function
Public Sub WaitForPageLoad()
While Not mPageReady
Application.DoEvents()
End While
mPageReady = False
End Sub
Private Sub PageWaiter(ByVal sender As Object,ByVal e As WebbrowserDocumentCompletedEventArgs)
If Me.Webbrowser1.ReadyState = WebbrowserReadyState.Complete Then
mPageReady = True
End If
End Sub
Private Sub BtnSignin_Click(sender As Object,e As EventArgs) Handles BtnSignin.Click
LoginUser(mEmailAddress,mPassword)
End Sub
解决方法
在进一步测试并更正了我的新代码之后，我能够完成登录过程。这是带有一串“ debug.writeline”语句的代码。
Private Sub BtnSignIn_Click(sender As Object,e As EventArgs) Handles BtnSignIn.Click
Dim myURL As String = "https://login.wlpc.com/index.php/"
AddHandler Me.WebBrowser1.DocumentCompleted,New WebBrowserDocumentCompletedEventHandler(AddressOf WebBrowserDocumentCompleted)
Me.WebBrowser1.Navigate(myURL)
End Sub
Private Sub WebBrowserDocumentCompleted(ByVal sender As Object,ByVal e As WebBrowserDocumentCompletedEventArgs)
If Me.WebBrowser1.ReadyState <> WebBrowserReadyState.Complete Then
Debug.WriteLine(Me.WebBrowser1.ReadyState.ToString)
Return
End If
Try
Const lEmailAddress As String = "TestEmail@somewhere.com"
Const lThisPassword As String = "SimplePassword"
' get the form: <form action="/index.php" method="POST" name="login">
Dim lFormHtmlElement As HtmlElement = Nothing ' the form element
Dim lFormFound As Boolean ' can we find the form?
For Each lFormHtmlElement In WebBrowser1.Document.Forms()
If lFormHtmlElement.Name = "login" Then
lFormFound = True
Exit For
End If
Next
If Not lFormFound Then
Debug.WriteLine("Can't find form")
Exit Sub
End If
'<input type="email" name="email" value="" tabindex="1" placeholder="name@example.com">
Dim lEmail As HtmlElement = lFormHtmlElement.Document.GetElementById("email")
If IsNothing(lEmail) Then
Debug.WriteLine("lEmail element is nothing")
Exit Sub
Else
Debug.WriteLine("lEmail element was found")
End If
If IsNothing(lEmail.GetAttribute("value")) Then
Debug.WriteLine("lEmail attribute value is nothing before set")
Else
Debug.WriteLine("lEmail attribute value is contains '" & lEmail.GetAttribute("value") & "' before set")
End If
lEmail.SetAttribute("value",lEmailAddress)
If IsNothing(lEmail.GetAttribute("value")) Then
Debug.WriteLine("lEmail value is nothing after set")
ElseIf lEmail.GetAttribute("value") = lEmailAddress Then
Debug.WriteLine("lEmail set to: '" & lEmail.GetAttribute("value") & "'")
End If
'<input type="password" name="password" id="password1" size="25" tabindex="2">
Dim lPassword As HtmlElement = lFormHtmlElement.Document.GetElementById("password")
Dim lPassword1 As HtmlElement = lFormHtmlElement.Document.GetElementById("password1")
If IsNothing(lPassword) Then
Debug.WriteLine("lPassword element is nothing")
Exit Sub
Else
Debug.WriteLine("lPassword element was found")
End If
If IsNothing(lPassword1) Then
Debug.WriteLine("lPassword1 element is nothing")
Exit Sub
Else
Debug.WriteLine("lPassword1 element was found")
End If
If lPassword.Document.Body.InnerText = lPassword1.Document.Body.InnerText Then
Debug.WriteLine("lPassword and lPassword1 same body innertext")
Else
Debug.WriteLine("lPassword and lPassword1 have different body innertext")
End If
If IsNothing(lPassword.GetAttribute("value")) Then
Debug.WriteLine("lPassword attribute value is nothing before set")
Else
Debug.WriteLine("lPassword attribute value is contains '" & lPassword.GetAttribute("value") & "' before set")
End If
If IsNothing(lPassword1.GetAttribute("value")) Then
Debug.WriteLine("lPassword1 attribute value is nothing before set")
Else
Debug.WriteLine("lPassword1 attribute value is contains '" & lPassword1.GetAttribute("value") & "' before set")
End If
lPassword.SetAttribute("value",lThisPassword)
If IsNothing(lPassword.GetAttribute("value")) Then
Debug.WriteLine("lPassword attribute value is nothing after set")
Exit Sub
ElseIf lPassword.GetAttribute("value") = lThisPassword Then
Debug.WriteLine("lPassword set to: '" & lPassword.GetAttribute("value") & "'")
End If
If IsNothing(lPassword1.GetAttribute("value")) Then
Debug.WriteLine("lPassword1 is nothing")
ElseIf lPassword1.GetAttribute("value") = lThisPassword Then
Debug.WriteLine("lPassword1 attribute value is same password value as lPassword attribute value")
End If
'<button type="submit" name="cmd" value="cred_set" tabindex="3">
Dim lCmdButton As HtmlElement = lFormHtmlElement.Document.GetElementById("cmd")
If IsNothing(lCmdButton) Then
Debug.WriteLine("lCmdButton element is nothing")
Else
Debug.WriteLine("lCmdButton element was found")
' found the 'cmd' button so click it
lCmdButton.InvokeMember("click")
End If
Catch ex As Exception
Debug.WriteLine("exception: " & ex.Message)
Finally
RemoveHandler Me.WebBrowser1.DocumentCompleted,AddressOf WebBrowserDocumentCompleted
End Try
End Sub