ADO OriginalValue 和 UnderlyingValue 属性
定义和用法
OriginalValue 属性可返回一个 variant 值，该值包含最后一次 Update 或 UpdateBatch 方法调用之前已经存在的字段值。
UnderlyingValue 属性可返回一个 variant 值，该值包含某个字段的当前值。该值不会必要地显示由其他用户造成的更改，且也许不是最新的值。
Kuwaita:Za a yi a hanyan Recordset object na Resync attribute domin a girmawa da zai zai zai a hanyan Field collection.
Kuwaita:Anan da za a yi a hanyan kaiya, za a iya da iya yin da zai kaiya bata na zai kaiya yau.
Yanmu
objField.OriginalValue objField.UnderlyingValue
Tasiri
<%
set conn=Server.CreateObject("ADODB.Connection")
conn.Provider="Microsoft.Jet.OLEDB.4.0"
conn.Open "c:/webdata/northwind.mdb"
set rs = Server.CreateObject("ADODB.Recordset")
rs.open "customers", conn
set objfield=rs.fields("companyname")
Kodin da a hanyan...
'Check for changes
rs.movefirst
while rs.eof=false
if objfield.OriginalValue<>objfield.UnderlyingValue then
response.write("Data has changed!<br />")
response.write("Original value: ")
response.write(objfield.OriginalValue & "<br />")
response.write("Current value: ")
response.write(objfield.UnderlyingValue & "<br />")
end if
rs.movenext
next
'More code...................
rs.Close
conn.close
%>
