[Apache Freemarker] macro variable example

Purpose

Macro variable stores a template fragment that can be used as user-defined directive. The variable also stores the name of allowed parameters to the user-defined directive. You must give value for all of those parameters when you use the variable as directive, except for parameters that has a default value. The default value will be used if and only if you don't give value for the parameter when you call the macro.

How-To

Here has two examples:

<#-- 取得現在時間 -->
<#assign aDateTime = .now>
<#-- 只保留日期 -->
<#assign aDate = aDateTime?date>
<#-- create the macro variable: -->
<#macro printDate mingguodate>
列印日期：${mingguodate}

</#macro>
<#macro footer records amount>
${"-"?right_pad(25, "-")}
總筆數：${records}
總金額：${amount}
</#macro>
<#-- call the macro: -->
<@printDate mingguodate="${aDate?string.@mingguo}" />
<#assign total = 0>
${"水果名稱"?right_pad(10)}${"單價"?right_pad(10)}${"訂購數量"?right_pad(10)}
${"-"?right_pad(25, "-")}
<#list rows as row>
<#assign total += row.price * row.quantity>
${row.name?right_pad(10)}${row.price?string.@ntd?left_pad(10)}${row.quantity?left_pad(10)}
</#list>
<#-- call the macro: -->
<@footer records="${rows?size?left_pad(10)}" amount="${total?string.@ntd?left_pad(10)}" />