就是告訴你如何判斷一個文件是否在inte.net explorer的緩存中，以滿足你的須要。
新建一個項目、添加一個模塊。將以下代碼寫到模塊里：
private const error_insufficient_buffer = 122
private const eeerrorbase = 26720
private type filetime
dwlowdatetime as long
dwhighdatetime as long
end type
private type internet_cache_entry_info
dwstructsize as long
lpszsourceurlname as string
lpszlocalfilename as string
cacheentrytype as string
dwusecount as long
dwhitrate as long
dwsizelow as long
dwsizehigh as long
lastmodifiedtime as filetime
expiretime as filetime
lastaccesstime as filetime
lastsynctime as filetime
lpheaderinfo as long
dwheaderinfosize as long
lpszfileextension as string
dwreserved as long
end type
private declare function geturlcacheentryinfo lib "wininet.dll" _
alias "geturlcacheentryinfoa" (byval surlname as string, _
lpcacheentryinfo as any, lpdwcacheentryinfobuffersize _
as long) as long
’用來報告api產生的錯誤：
private const format_message_allocate_buffer = &h100
private const format_message_argument_array = &h2000
private const format_message_from_hmodule = &h800
private const format_message_from_string = &h400
private const format_message_from_system = &h1000
private const format_message_ignore_inserts = &h200
private const format_message_max_width_mask = &hff
private declare function formatmessage lib "kernel32" alias _
"formatmessagea" (byval dwflags as long, lpsource as any, _
byval dwmessageid as long, byval dwlanguageid as long, _
byval lpbuffer as string, byval nsize as long, arguments _
as long) as long
public function winapierror(byval llastdllerror as long) as string
dim sbuff as string
dim lcount as long
’返回與lastdllerror相關的出錯信息：
sbuff = string$(256, 0)
lcount = formatmessage( _
format_message_from_system or format_message_ignore_inserts, _
0, llastdllerror, 0&, sbuff, len(sbuff), byval 0)
if lcount then
winapierror = left$(sbuff, lcount)
end if
end function
public function getcacheentryinfo(byval hwnd as long, _
byval lpszurl as string) as boolean
dim dwentrysize as long
dim lpcacheentry as internet_cache_entry_info
dim dwtemp as long
dim lerr as long
if (geturlcacheentryinfo(lpszurl, byval 0&, dwentrysize)) = 0 then
lerr = err.lastdllerror
if (lerr <> error_insufficient_buffer) then
’預料外的錯誤。須要顯示出錯原因：
err.raise eeerrorbase + 1, _
app.exename & ".mcacheentry", winapierror(lerr)
getcacheentryinfo = false
exit function
else
’這是預料中的錯誤
getcacheentryinfo = true
end if
end if
end function
在窗體上添加一個command和一個text。然后加入這些代碼：
option explicit
private sub command1_click()
on error goto errorhandler
’檢查text中的url地址是否出現在緩存中：
if (getcacheentryinfo(me.hwnd, text1.text)) then
msgbox "url in cache.", vbinformation
else
msgbox "url not in cache.", vbinformation
end if
exit sub
errorhandler:
msgbox "url not in cache [" & err.description & "]",vbinformation
end sub
運行，在text中鍵入一個url地址（比如，http://www.vbaccelerator.com/index.html）當你按下command按鈕時，就會得到一則消息報告url在不在緩存中。如果windows給出了url沒找到的原因，它將被顯示在隨后的的方括號內。
文章來源于領測軟件測試網 http://www.kjueaiud.com/
