主题：登录代码

Dim uName As String = e.Form.Controls("txtName").Value
Dim pwd As String = e.Form.Controls("txtpwd").value
Dim cmd As New SQLCommand
Dim dt As DataTable
Dim dr As DataRow
cmd.C
If uName = "" Then
    Messagebox.show("请输入用户名!","提示",MessageBoxButtons.OK,MessageBoxIcon.Warning)
    Return
Else If pwd = ""
    Messagebox.show("密码不能为空!","提示",MessageBoxButtons.OK,MessageBoxIcon.Warning)
    Return
End If
cmd.CommandText = "Select * From {userInfo} Where [userID] = '" & uName.trim() & "'"
dt = cmd.ExecuteReader
If dt Is not Nothing Then 
    dr = dt.DataRows(0)
    If e.Form.Controls("txtpwd").Value = dr("userPwd").trim() Then
        _UserName = uName
        _UserGroup = dr("userDES")
        MessageBox.Show("登录成功!","提示",MessageBoxButtons.OK,MessageBoxIcon.Information)
    Else
        Messagebox.show("密码错误!" ,"提示",MessageBoxButtons.OK,MessageBoxIcon.Warning)
    End If
Else
    MessageBox.Show("用户名或密码错误,请重新输入!","提示",MessageBoxButtons.OK,MessageBoxIcon.Warning)
    e.Form.Controls("txtpwd").value = ""
End If