使用VBA代码进行Web抓取:如何浏览登录页面？

Sub LoginToWebsite()
    Dim ie As Object
    Dim loginUrl As String
    Dim loginData As String
    
    ' 创建并打开一个新的 Internet Explorer 实例
    Set ie = CreateObject("InternetExplorer.Application")
    ie.Visible = True
    
    ' 登录页面的URL
    loginUrl = "https://example.com/login"
    
    ' 将需要提交的登录表单数据进行URL编码
    loginData = "username=" & URLEncode("your_username") & "&password=" & URLEncode("your_password")
    
    ' 打开登录页面
    ie.Navigate loginUrl
    
    ' 等待页面加载完成
    Do While ie.Busy Or ie.readyState <> 4
        DoEvents
    Loop
    
    ' 填写登录表单并提交
    With ie.document.forms(0)
        .elements("username").Value = "your_username"
        .elements("password").Value = "your_password"
        .submit
    End With
    
    ' 等待页面重新加载完成
    Do While ie.Busy Or ie.readyState <> 4
        DoEvents
    Loop
    
    ' 可以在此处进行后续的抓取操作
    
    ' 关闭 Internet Explorer 实例
    ie.Quit
    Set ie = Nothing
End Sub

Function URLEncode(ByVal str As String) As String
    Dim i As Integer
    Dim charCode As Integer
    Dim result As String
    
    For i = 1 To Len(str)
        charCode = Asc(Mid(str, i, 1))
        
        If charCode < 128 Then
            result = result & "%" & Hex(charCode)
        Else
            result = result & "%" & Hex(charCode \ 256) & "%" & Hex(charCode Mod 256)
        End If
    Next i
    
    URLEncode = result
End Function