amazon-web-services - 在 Apache Velocity 模板语言中追加字符串变量

Question

我想在 API 网关映射模板中构造查询字符串。我有这样的东西

#foreach($entry in $entries)
  #set($count = $foreach.count)
  #set($entriesQueryString = "$!{entriesQueryString}Id=${count}&"
#end

想法是只要输入中提供了条目就追加新字符串。

我的代码有效吗？还有其他方法可以追加吗？

Answer 1

根据 this post和 VTL user guide page ，连接的方式只是通过“将项目放在一起”。来自 VTL 指南:

A common question that developers ask is How do I do String concatenation? Is there any analogue to the '+' operator in Java?.To do concatenation of references in VTL, you just have to 'put them together'. The context of where you want to put them together does matter, so we will illustrate with some examples.In the regular 'schmoo' of a template (when you are mixing it in with regular content) :

#set( $size = "Big" )
#set( $name = "Ben" )
The clock is $size$name.

所以我想这是唯一的方法。