Batch file fails to set environment variable within conditional statement

Question

Why does the following Windows Batch File output Foo followedby Bar, rather than Baz?

@echo off
setlocal

set _=Foo
echo %         


        

Answer 1

try this

@echo off
setlocal

set _=Foo
echo %_%
set _=Bar
if "1" NEQ "2" goto end
set _=Baz
echo %_%
:end