怎么编程把用户名，密码提交到网页上的登录页？

首先在程序中加入Webbrowser控件并加入引用 Microsoft HTML Object Library。
假设你的HTML页面表单代码如下：
<form method="POST" action="http://chen/dll/chat/chatmain.exe/RegUser">
   <p>请填写下面表单注册（*项为必添项）</p>
   <p>*姓名<input type="text" name="Name" size="20"></p>
   <p>*昵称<input type="text" name="NickName" size="20"></p>
   <p>电子邮件<input type="text" name="EMail" size="20"></p>
   <p>*密码<input type="text" name="Password" size="20"></p>
   <p><input type="submit" value="提交" name="B1"><input type="reset" value="全部重写" name="B2"></p>
</form>
注意其中元素的type、Name、value属性。然后VB中的代码如下：
Private Sub Command1_Click()
     WebBrowser1.Navigate "http://chen/chat/newuser.htm"
End Sub

Private Sub WebBrowser1_DocumentComplete(ByVal pDisp As Object, URL As Variant)
     Dim vDoc, vTag
     Dim i As Integer
     
     Set vDoc = WebBrowser1.Document
     List1.Clear
     For i = 0 To vDoc.All.length - 1
         If UCase(vDoc.All(i).tagName) = "INPUT" Then
             Set vTag = vDoc.All(i)
             If vTag.Type = "text" Or vTag.Type = "password" Then
                 List1.AddItem vTag.Name
                 Select Case vTag.Name
                     Case "Name"
                         vTag.Value = "IMGod"
                     Case "NickName"
                         vTag.Value = "IMGod"
                     Case "Password"
                         vTag.Value = "IMGodpass"
                     Case "EMail"
                         vTag.Value = "[e-mail]"
                 End Select
             ElseIf vTag.Type = "submit" Then
                 vTag.Click
             End If
         End If
     Next i
End Sub
点击Command1就可以自动填表并提交了。