public function digestfiletohexstr(filename as string) as string
open filename for binary access read as #1
md5init
do while not eof(1)
get #1, , bytebuffer
if loc(1) < lof(1) then
bytecounter = bytecounter + 64
md5transform bytebuffer
end if
loop
bytecounter = bytecounter + (lof(1) mod 64)
close #1
md5final
digestfiletohexstr = getvalues
end function
'
' function to digest a text string and output the result as a string
' of hexadecimal characters.
'
public function digeststrtohexstr(sourcestring as string) as string
md5init
md5update len(sourcestring), stringtoarray(sourcestring)
md5final
digeststrtohexstr = getvalues
end function
'
' a utility function which converts a string into an array of
' bytes.
'
private function stringtoarray(instring as string) as byte()
dim i as integer
dim bytbuffer() as byte
redim bytbuffer(len(instring))
for i = 0 to len(instring) - 1
bytbuffer(i) = asc(mid(instring, i + 1, 1))
next i
stringtoarray = bytbuffer
end function
'
' concatenate the four state vaules into one string
'
public function getvalues() as string
getvalues = longtostring(state(1)) & longtostring(state(2)) & longtostring(state(3)) & longtostring(state(4))
end function
'
' convert a long to a hex string
'
private function longtostring(num as long) as string
dim a as byte
dim b as byte
dim c as byte
dim d as byte
a = num and &hff&
if a < 16 then
longtostring = "0" & hex(a)
else
longtostring = hex(a)
end if
b = (num and &hff00&) \ 256
if b < 16 then
longtostring = longtostring & "0" & hex(b)
else
longtostring = longtostring & hex(b)
end if
c = (num and &hff0000) \ 65536
if c < 16 then
longtostring = longtostring & "0" & hex(c)
else
longtostring = longtostring & hex(c)
end if
if num < 0 then
d = ((num and &h7f000000) \ 16777216) or &h80&
else
d = (num and &hff000000) \ 16777216
end if
if d < 16 then
longtostring = longtostring & "0" & hex(d)
else
longtostring = longtostring & hex(d)
end if
end function
'
' initialize the class
' this must be called before a digest calculation is started
'
