Multiple IF Conditions

Prev: Handling Events in a VBScript Class
Next: wshremote not running script on remote computer

From: Al Dunbar on 5 Jul 2008 01:24

---

"Richard Mueller [MVP]" <rlmueller-nospam(a)ameritech.nospam.net> wrote in
message news:eBtb1GY3IHA.3480(a)TK2MSFTNGP03.phx.gbl...
>
> "preet" <preetkanwaljit> wrote in message
> news:eI9RTXV3IHA.5060(a)TK2MSFTNGP02.phx.gbl...
>> Is there a better way to handle multiple IF Conditions like
>>
>>
>> IF condition1 AND condition2 AND condition3 AND .... THEN
>>
>> code
>>
>> END IF
>>
>>
>> Now suppose i have 30 to 40 conditions to test, how do i handle this
>> snippet in an easier manner.
>>
>> Guide
>
> I don't think there is a better way. In theory if you know that one or a
> few of the conditions are more likely to be false, the code could be more
> efficient if you nested the If statements, testing the ones likely to be
> false first. Then the remaining conditions are seldom evaluated. For
> example, if condition1, condition2, and condition3 are more likely to be
> false than the others:
>
> If condition1 Then
> If condition2 Then
> If condition 3 Then
> If condition4 And condition5 And condition6 Then
> ' ... code.
> End If
> End If
> End If
> End If
>
> Even here I doubt you could tell the difference, even with 40 conditions.

There is a way to reduce the nesting from any number of levels to one:

a = "a"
b = "b"
c = "ZZZ"

do
if not a = "a" then exit do
if not b = "b" then exit do
if not c = "c" then exit do

wscript.echo "test1: all conditions are true"
loop until true

c = "c"

do
if not a = "a" then exit do
if not b = "b" then exit do
if not c = "c" then exit do

wscript.echo "test2: all conditions are true"
loop until true

If you need an "else" clause, then:

a = "a"
b = "b"
c = "ZZZ"

do
test1 = false
if not a = "a" then exit do
if not b = "b" then exit do
if not c = "c" then exit do
test1 = true
loop until true

if test1 then
wscript.echo "all conditions were true"
else
wscript.echo "at least one conditions was false"
end if


/Al


> --
> Richard Mueller
> MVP Directory Services
> Hilltop Lab - http://www.rlmueller.net
> --
>
>

From: Dr J R Stockton on 5 Jul 2008 11:32

---

In microsoft.public.scripting.vbscript message <eBtb1GY3IHA.3480(a)TK2MSFT
NGP03.phx.gbl>, Thu, 3 Jul 2008 21:57:19, "Richard Mueller [MVP]"
<rlmueller-nospam(a)ameritech.nospam.net> posted:

>I don't think there is a better way. In theory if you know that one or a few
>of the conditions are more likely to be false, the code could be more
>efficient if you nested the If statements, testing the ones likely to be
>false first.

Not necessarily; some conditions take more work than others.

--
(c) John Stockton, nr London, UK. ?@merlyn.demon.co.uk Turnpike v6.05 MIME.
Web <URL:http://www.merlyn.demon.co.uk/> - FAQish topics, acronyms, & links.
Proper <= 4-line sig. separator as above, a line exactly "-- " (SonOfRFC1036)
Do not Mail News to me. Before a reply, quote with ">" or "> " (SonOfRFC1036)

First  |  Prev  | 
Pages: 1 2
Prev: Handling Events in a VBScript Class
Next: wshremote not running script on remote computer