我按照帮助一步一步做的,用户管理及增加用户、删除用户、更改用户都可以，就是用户登录不行，提示密码错误。是不是帮助中没有读上控件中所输的密码啊？

以下是帮助示例

八、增加一个名为“用户登录”的窗口：

窗口的AfterLoad事件代码为：

Dim cmd As New SQLCommand
Dim dt As DataTable
Dim cmb As WinForm.ComboBox = e.Form.Controls("UserName")
cmd.ConnectionName = "User"
cmd.CommandText = "SELECT DISTINCT Name From {Users}"
dt = cmd.ExecuteReader()
For Each dr As DataRow In dt.Datarows
    cmb.Items.Add(dr("Name"))
Next
cmb.SelectedIndex = 0

"确定"按钮的代码为：

Dim UserName As String = e.Form.Controls("UserName").Value
Dim cmd As New SQLCommand
Dim dt As DataTable
Dim dr As DataRow
cmd.ConnectionName = "User"
If UserName = "" Then
    Messagebox.show("请选择用户!","提示",MessageBoxButtons.OK,MessageBoxIcon.Information)
    Return
End If
cmd.CommandText = "Select * From {Users} Where [Name] = \'" & UserName & "\'"
dt = cmd.ExecuteReader
dr = dt.DataRows(0)
If e.Form.Controls("PassWord").Value = dr("Password") Then
    _UserName = UserName
    _UserGroup = dr("Group")
    e.Form.Close
Else
    Messagebox.show("密码错误!","提示",MessageBoxButtons.OK,MessageBoxIcon.Information)
End If

“取消”按钮的代码为：

e.Form.Close()
Syscmd.Project.Exit()

为了防止用户跳过确定和取消按钮，直接关闭窗口，请将窗口的“显示控制框”属性设置为False。