[RESOLVED] Input Error Checking

[Strider]

when performing input error checking on forms which is best to use?

If txtbox1.text = vbnullstring then
    lblErrorMsg.text = "Box 1 Empty"
End IF

or

If Request.Form.Item("txtbox1") = vbnullstring Then
    lblErrorMsg.text = "Box 1 Empty"
End If

basically what is the difference