由于各种字段属性不同，判断字段是否为空的方法也各异。

　　下面是一个通用函数，免去了还要看字段类型之苦。

'Check a variable isn't "empty"
Function IsBlank(ByRef TempVar)
'by default, assume it's not blank
IsBlank = False
'now check by variable type
Select Case VarType(TempVar)
'Empty & Null
Case 0, 1
IsBlank = True
'String
Case 8
If Len(TempVar) = 0 Then
IsBlank = True
End If
'Object
Case 9
tmpType = TypeName(TempVar)
If (tmpType = "Nothing") Or (tmpType = "Empty") Then
IsBlank = True
End If
'Array
Case 8192, 8204, 8209
'does it have at least one element?
If UBound(TempVar) = -1 Then
IsBlank = True
End If
End Select
End Function
应用实例：

If IsBlank(rs("upic")) Then
upicurl="/images/nonepic.jpg"
Else
upicurl=rs("upic")
End If