code:

---

function ipmask($ipaddress1, $ipaddress2)
Dim $bit if instr($ipaddress1,'.') or instr($ipaddress2,'.') or len($ipaddress1)<>32 or 

len($ipaddress2)<>32
exit 87
endif $ipmask=''
for $bit=1 to 32
$ipmask=$ipmask+(val(substr($ipaddress1,$bit,1)) & val(substr($ipaddress2,$bit,1)))
next
endfunction
function isiniprange($ipaddress,$iprangearray)
Dim $iprange, $networkid, $subnetmask, $bit

if $ipaddress=''
exit 87
endif

$ipaddress=binaryip($ipaddress)

for each $iprange in $iprangearray

if instr($iprange,'/') 
$iprange=split($iprange,'/')
$networkid=binaryip($iprange[0])

if instr($iprange[1],'.')
$subnetmask=binaryip($iprange[1])
else
$subnetmask=''
for $bit=1 to val($iprange[1])
$subnetmask=$subnetmask+'1'
next
for $bit=(val($iprange[1])+1) to 32
$subnetmask=$subnetmask+'0'
next
endif

if isinsubnet($ipaddress,$networkid,$subnetmask)
$isiniprange=1
return
else
$isiniprange=0
endif
endif
next
endfunction
DIM $iparray[0]
DIM $iparray[1]
DIM $iparray[2]
$ipaddress=@IPADDRESS0
$iparray[0]='10.0.28.0/24'
$iparray[1]='10.0.40.0/24'
$iparray[2]='10.0.27.0/24
call "isiniprange.udf"
IF isiniprange($ipaddress,$iparray[0])
MessageBox ("Welcome to IRRI",0,35 )
ENDIF
:EXIT
Exit

Also Tried this Code:

$ipaddress=@IPADDRESS0
$iparray[0]='10.0.28.0/24'
$iparray[1]='10.0.28.0/255.255.255.0'
$iparray[2]='10.0.28.49/255.0.0.0'
IF isiniprange($ipaddress,$iparray)
MessageBox ("Welcome to IRRI",0,35 )
ENDIF

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