http://hi.baidu.com/xqaizx1314/blog/item/c1e6e10b1bd71988d1581bb0.html
其实很简单，只需要用到javascript，因为.net的webform的后台代码无法调用cmd.exe。
你最多在用脚本在添加点时间控制的代码。
我这里是对orcle的备份
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<script language =vbscript>
dim expstr
select case Weekday(date)
case 1
expstr = "jlsbgis/jlsbgis@sj owner=jlsbgis file=D:/database/sj" & year(date) & month(date) & day(date) & ".dmp log=c:/temp/expost.log"
case 2
expstr = "jlsbgis/jlsbgis@spgd owner=jlsbgis file=D:/database/spgd" & year(date) & month(date) & day(date) & ".dmp log=c:/temp/expost.log"
case 3
expstr = "jlsbgis/jlsbgis@jlgd owner=jlsbgis file=D:/database/jlgd" & year(date) & month(date) & day(date) & ".dmp log=c:/temp/expost.log"
case 4
expstr = "jlsbgis/jlsbgis@spgd owner=jlsbgis file=D:/database/spgd" & year(date) & month(date) & day(date) & ".dmp log=c:/temp/expost.log"
case 5
expstr = "jlsbgis/jlsbgis@bsgd owner=jlsbgis file=D:/database/bsgd" & year(date) & month(date) & day(date) & ".dmp log=c:/temp/expost.log"
case 6
expstr = "jlsbgis/jlsbgis@sj owner=jlsbgis file=D:/database/sj" & year(date) & month(date) & day(date) & ".dmp log=c:/temp/expost.log"
case 7
expstr = "jlsbgis/jlsbgis@thgd owner=jlsbgis file=D:/database/thgd" & year(date) & month(date) & day(date) & ".dmp log=c:/temp/expost.log"
end select
set objshell = CreateObject("Shell.Application")
objshell.shellexecute "exp", expstr
if err.number <> 0 then
msgbox "oracle 可能出现问题，请询问黄总。" & chr(10) &chr(10) & "错误代码：" & err.Description ,,"提示"
end if
set objShell = nothing
</script>