主题：狐表集成Seafile私有云系统

Seafile私有云系统可自行安装在服务器上：www.seafile.com，开源免费。

只需窗口放置一个Webbrowser控件即可，代码如下：

Dim web As System.Windows.Forms.WebBrowser = e.Form.controls("webbrowser1").basecontrol
web.ScriptErrorsSuppressed = True
web.Navigate("http://123.57.251.28:8000/accounts/login/")
Do Until web.ReadyState = 4
 Application.DoEvents
Loop
Dim btns = web.Document.GetElementsByTagName("csrfmiddlewaretoken")
For Each btn As object In btns
If btn.getattribute("name") = "login" Then
btn.setattribute("value", "foxtable@163.com")
ElseIf btn.getattribute("name") = "password" Then
 btn.setattribute("value", "123456")
End If
Next
btns = web.Document.GetElementsByTagName("a")
For Each btn As object In btns
If btn.getattribute("href") = "javascript:login_onsubmit(0);" Then  '这里不需要该了吗？
 btn.InvokeMember("click")
End If
Next

前面没有问题，后面不需要改了吗？这样也登录不了。

.NET Framework 版本：2.0.50727.8784
Foxtable 版本：2017.6.12.1
错误所在事件：窗口,窗口1,AfterLoad
详细错误信息：
未设置对象变量或 With 块变量。

Dim web As System.Windows.Forms.WebBrowser = e.Form.controls("webbrowser1").basecontrol
web.ScriptErrorsSuppressed = True
web.Navigate("http://123.57.251.28:8000/accounts/login/")
Do Until web.ReadyState = 4
    Application.DoEvents
Loop
MessageBox.show("1")  '以下开始出错
Dim el = web.Document.GetElementByID("login")
el.setattribute("value", "foxtable@163.com")
MessageBox.show("2")
Dim el2 = web.Document.GetElementByID("password")
el2.setattribute("value", "123456")
MessageBox.show("3")
Dim btns = web.Document.GetElementsByTagName("input")
MessageBox.show("4")
For Each btn As object In btns
    If btn.getattribute("value") = "登录" Then
        btn.InvokeMember("click")
    End If
Next

多谢版主，两个都判断以下就OK.从而实现FT集成私有云系统。

Dim web As System.Windows.Forms.WebBrowser = e.Form.controls("webbrowser1").basecontrol

web.ScriptErrorsSuppressed = True
web.Navigate("http://123.57.251.28:8000/accounts/login/")
Do Until web.ReadyState = 4
 Application.DoEvents
Loop
Dim el = web.Document.GetElementByID("login")
If el IsNot Nothing Then
el.setattribute("value", "foxtable@163.com")
End If
Dim el2 = web.Document.GetElementByID("password")
If el2 IsNot Nothing Then
el2.setattribute("value", "123456")
End If
Dim btns = web.Document.GetElementsByTagName("input")
For Each btn As object In btns
If btn.getattribute("value") = "登录" Then
 btn.InvokeMember("click")
 End If
Next