There are 2 kinds of conditions: if blocks and switch blocks.

if blocks allow you to only execute a portion of the script if some condition is true. If the condition is false, you can then run another portion of script if another condition is true, or run a portion of script if the condition was false.

Every if needs a matching end. This rule must not be broken or your script will have unwanted behavior.

The simplest form is below. A single condition and block of code.

if %foo%
   ... CODE IF FOO IS TRUE ...
end

The more complex form has a single condition, and two blocks of code.

if %foo%
   ... CODE IF FOO IS TRUE ...
else
   ... CODE IF FOO IS FALSE ...
end

The next form has two conditions, and two blocks of code. Note that it is elseif not else if, and because it is elseif not if, we don't need a matching end.

if %foo%
   ... CODE IF FOO IS TRUE ...
elseif %bar%
   ... CODE IF FOO IS FALSE AND BAR IS TRUE ...
end

The final form has 2 conditions and 3 blocks of code, mixing elseif and else.

if %foo%
   ... CODE IF FOO IS TRUE ...
elseif %bar%
   ... CODE IF FOO IS FALSE AND BAR IS TRUE ...
else
   ... CODE IF BOTH FOO AND BAR ARE FALSE ...
end

To summarize, if blocks consist of:

• Begin with an if
• Follow with zero or more elseif
• Follow with zero or one else
• Follow with an end

You can put if blocks within if blocks, but every if must have an end:

if %foo%
   if %baz%
      ... CODE IF FOO IS TRUE AND BAZ IS TRUE ...
   end
   ... CODE IF FOO IS TRUE (EVEN IF BAZ IS TRUE) ...
elseif %bar%
   ... CODE IF FOO IS FALSE AND BAR IS TRUE ...
end

-- FearItself - 27 Mar 2005