Difference between *, $, and #

Question

I am new to thymeleaf and see these three operators often. What is the difference between *{} ${} and #{}?

I know they are for accessing data from the MVC but in what context?

Answer 1

The types of expressions Thymeleaf supports are:

1. ${...} - Variable Expressions. These are the standard expressions.
2. *{...} - Selection Variable Expressions. These are the same as variable expressions, except that they are used in combination with a a th:object attribute. For example, if you have <form th:object="${form}">, then the expression *{field} resolves to ${form.field}. These are mostly used when using th:field attributes while creating a form.
3. #{...} - Message Expressions. These expressions are mainly used to externalize text. For example, to provide text in different languages by reading from a messages file.
4. @{...} - Link URL Expressions. Used to generate URLs, see the standard url syntax.
5. ~{...} - Fragment Expression. Used to specify which fragment to include, see fragment specification syntax.

Answer 2

The documentation provides very nice examples so give it a look.

In short:

${} used for variable expressions. Variable expressions are OGNL expressions –or Spring EL if you’re integrating Thymeleaf with Spring

*{} is used for selection expressions. Selection expressions are just like variable expressions, except they will be executed on a previously selected object.

#{} is used for message (i18n) expressions. Used to retrieve locale-specific messages from external sources