if,elseif,else
if statements in Smarty have much the same flexibility as php if statements,
with a few added features for the template engine. Every
must be paired with an
elseif
are also permitted. "eq", "ne","neq", "gt", "lt", "lte", "le", "gte" "ge","is
even","is odd", "is not even","is not odd","not","mod","div by","even by","odd
by","==","!=",">", "<","<=",">=" are all valid conditional qualifiers,
and must be separated from surrounding elements by spaces.
Smarty 中的 if 语句和 php 中的 if 语句一样灵活易用，并增加了几个特性以适宜模板引擎. if 必须于 /if 成对出现. 可以使用 else
和 elseif 子句. 可以使用以下条件修饰词：eq、ne、neq、gt、lt、lte、le、gte、ge、is even、is odd、is not
even、is not odd、not、mod、div by、even by、odd by、==、!=、>、<、<=、>=.
使用这些修饰词时必须和变量或常量用空格格开.
{* the following syntax will NOT work, conditional qualifiers
must be separated from surrounding elements by spaces *}
{if $name=="Fred" || $name=="Wilma"}
{/if}
{* parenthesis are allowed *}
{if ( $amount < 0 or $amount > 1000 ) and $volume >= #minVolAmt#}
{/if}
{* you can also embed php function calls *}
{if count($var) gt 0}
{/if}
{* test if values are even or odd *}
{if $var is even}
{/if}
{if $var is odd}
{/if}
{if $var is not odd}
{/if}
{* test if var is divisible by 4 *}
{if $var is div by 4}
{/if}
{* test if var is even, grouped by two. i.e.,
0=even, 1=even, 2=odd, 3=odd, 4=even, 5=even, etc. *}
{if $var is even by 2}
{/if}
{* 0=even, 1=even, 2=even, 3=odd, 4=odd, 5=odd, etc. *}
{if $var is even by 3}
{/if}
