多亮你的背包mp3百度云:谁等解释下

这些代码主要的功能是什么？

Function LinkEmail(strInput)
Dim iCurrentLocation
Dim iLinkStart
Dim iLinkEnd
Dim strLinkText
Dim strOutPut

strLinkText=""
strOutput=""
iCurrentLocation=1
Do while Instr(iCurrentLocation,strInput,"[email]",1)<>0
iLinkStart=Instr(iCurrentLocation,strInput,"[email]",1)
iLinkEnd=Instr(iCurrentLocation+1,strInput,"[/email]",1)
If iLinkEnd=0 then iLinkEnd=len(strINput)+1
select case Mid(strInput,iLinkEnd-1,1)
case ".","!","?"
iLinkEnd=iLinkEnd-1
end select
stroutput=strOutput & Mid(strInput,iCurrentLocation,iLinkStart-iCurrentLocation)
strLinkText=replace(Mid(strInput,iLinkStart+7,iLinkEnd-iLinkStart-7),"[/email]","")
strOutput=strOutput & "<A href=""mailto:" & strLinkText & """><font color=blue>" & strLinkText & "</font></A>"
iCurrentLocation=iLinkEnd
Loop

strOutput=strOutput & Mid(strInput,iCurrentLocation)
LinkEmail=replace(strOutput,"[/email]","",1,-1,1)
End Function
function encrypt(ecode)
Dim texts
dim i
for i=1 to len(ecode)
texts=texts & chr(asc(mid(ecode,i,1))+i)
next
encrypt = texts
end function
function UBB(str)
str=LinkURLs(str)
str=LinkIMGs(str)
str=LinkEmail(str)
UBB=str
end function