Getting started with the Standard dialects in 5 minutes

文章总结
语法：

${...} : Variable expressions.
*{...} : Selection expressions.
#{...} : Message (i18n) expressions.
@{...} : Link (URL) expressions.
~{...} : Fragment expressions.

例子：

2.1 Variable expressions

取 session 中的变量：
1. ${session.user.name}
2. 

更复杂应用：
3. 

2.2 Selection expressions

与 Variable expressions 类似，
they will be executed on a previously selected object instead of the whole context variables map

示例：

1. *{customer.name}

2. 注意使用 th:object 标签

  ...
  ...
  ...

2.3 Message（i18n）expressions

国际化示例：

1. #{main.title}
2. #{message.entrycreated(${entryId})}
3. 模板中使用：

  ...
  
  ...
...
  
...
4. 高级用法：在 message expressions 中使用 variable expressions
#{${config.adminWelcomeKey}(${session.user.name})}

2.4 Link（URL）expressions

原文翻译：给 url 添加上 context 和 session 信息
Link expressions are meant to build URLs and add useful context and session info to them (a process usually called URL rewriting).

示例：
So for a web application deployed at the /myapp context of your web server, an expression such as:

...

Could be converted into something like this:

...

Or even this, if we need to keep sessions and cookies are not enabled (or the server doesn’t know yet):

...

URLs can also take parameters:

...

Resulting in something like this:

...

Link expressions can be relative, in which case no application context will be prefixed to the URL:

...

Also server-relative (again, no application context to be prefixed):

...

And protocol-relative (just like absolute URLs, but browser will use the same HTTP or HTTPS protocol used in the page being displayed):

...

And of course, Link expressions can be absolute:

...

But wait, in an absolute (or protocol-relative) URL… what value does the Thymeleaf Link Expression add? easy: the possibility of URL-rewriting defined by response filters: In a Servlet-based web application, for every URL being output (context-relative, relative, absolute…) Thymeleaf will always call the HttpServletResponse.encodeUrl(...) mechanism before displaying the URL. Which means that a filter can perform customized URL-rewriting for the application by means of wrapping the HttpServletResponse object (a commonly used mechanism).

2.5 Fragment expressions

最常用的两个属性：
th:insert or th:replace

示例：

1. div th:insert="~{commons :: main}">...

2.

Fragment expressions can have arguments:

2.5 Expression preprocessing

格式：specified between __
示例：#{selection.${sel.code}}

说明（未懂）：What we are seeing there is a variable expression (${sel.code}) that will be executed first and which result – let’s say, “ALL” – will be used as a part of the real expression to be executed afterwards, in this case an internationalization one (which would look for the message with key selection.ALL).