字符串和列表的 FreeMarker 映射

Question

我正在尝试将序列作为值添加到地图中：

<#assign client_sequence=['a', 'b']>
{
    clients: ${client_sequence},
    usecase_key: usecase_value,
    other_key: other_value
}

在上面的示例中，client_sequence 将从另一个无法更改的模块传递。我已经替换它来说明。

我收到以下错误：

 For "${...}" content: Expected a string or something automatically convertible to string (number, date or boolean), or "template output" , but this has evaluated to a sequence (wrapper: f.t.SimpleSequence):

==> client_sequence [无名模板第 3 行第 16 列]

  FTL stack trace ("~" means nesting-related):

- 失败于：${client_sequence} [无名模板第 3 行第 14 列]

Answer 1

使用 FreeMarker 序列的 join 内置逗号:

<#assign client_sequence=['a', 'b','c']>
{
    clients: ${client_sequence?join(", ")}
    usecase_key: usecase_value,
    other_key: other_value
}

Concatenates the items of a sequence to a single string, with the given separator.

字符串和列表的 FreeMarker 映射

FreeMarker Map of String and List

java

freemarker

- 失败于：${client_sequence} [无名模板第 3 行第 14 列]