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The OriginalValue property returns a variant that contains the field value as it existed right after the last Update or UpdateBatch method call.
OriginalValue属性的作用是:返回在发生任何更改前(即自从上次调用 Update 方法或UpdateBatch方法)已经存在的字段值。
The UnderlyingValue property returns a variant that contains the current value of a field. This value does not necessarily show changes made by other users and may not be the latest value.
UnderlyingValue属性的作用是:返回当前字段值。该值不显示其它用户的更改信息,且它不显示更新后的值。
Tip: Use the Resync property of the Recordset object to get the latest values for all of the Field objects in the Fields Collection.
提示:可以使用Recordset对象中的Resync属性获取字段集中最新的字段对象值。
Tip: These properties can be used together to prevent update conflicts.
提示:同时使用这些属性可以避免更新时发生冲突。
objField.OriginalValue objField.UnderlyingValue |
<% 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") 'Some code.................. '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 %> |