参考说明:以下笔记参考来自尚硅谷springboot教学中的笔记!
thymeleaf官网docs: https://www.thymeleaf.org/documentation.html
模板引擎:
JSP、Velocity、Freemarker、Thymeleaf
语法更简单,功能更强大;
1、引入thymeleaf:
<dependency> <groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-thymeleaf</artifactId> 2.1.6 </dependency>
切换thymeleaf版本 <properties> <thymeleaf.version>3.0.9.RELEASE</thymeleaf.version> <!-- 布局功能的支持程序 thymeleaf3主程序 layout2以上版本 --> <!-- thymeleaf2 layout1--> <thymeleaf-layout-dialect.version>2.2.2</thymeleaf-layout-dialect.version> </properties>
@ConfigurationProperties(prefix = "spring.thymeleaf") public class ThymeleafProperties { private static final Charset DEFAULT_ENCODING = Charset.forName("UTF-8"); private static final MimeType DEFAULT_CONTENT_TYPE = MimeType.valueOf("text/html"); public static final String DEFAULT_PREFIX = "classpath:/templates/"; public static final String DEFAULT_SUFFIX = ".html"; //
以上是package org.springframework.boot.autoconfigure.thymeleaf;包中的源码,放在这里主要是告诉你模块该如何配置;
只要我们把HTML页面放在classpath:/templates/,thymeleaf就能自动渲染;
(1) 导入thymeleaf的名称空间(导入后有语法提示)
<html lang="en" xmlns:th="http://www.thymeleaf.org">
(2) 使用thymeleaf语法:
<!DOCTYPE html> <html lang="en" xmlns:th="http://www.thymeleaf.org"> <head> <meta charset="UTF-8"> <title>Title</title> </head> <body> <h1>成功!</h1> <!--th:text 将div里面的文本内容设置为 --> <div th:text="${hello}">这是显示欢迎信息</div> </body> </html>
1)、th:text;改变当前元素里面的文本内容;
th:任意html属性;来替换原生属性的值(eg: th:id=1改变id的值, th:class=“c1”改变class的值)
补充:
<div th:remove="tag">
<div>唐嫣</div> //包含标记的标签将被删除,即这里的外层div将被删除 参考:th:remove用法
</div>
2)、表达式?
1、Simple expressions:(表达式语法) (1)Variable Expressions: ${...}:获取变量值;OGNL; 1)、获取对象的属性、调用方法 2)、使用内置的基本对象:
#ctx : the context object.
#vars: the context variables.
#locale : the context locale.
#request : (only in Web Contexts) the HttpServletRequest object.
#response : (only in Web Contexts) the HttpServletResponse object.
#session : (only in Web Contexts) the HttpSession object.
#servletContext : (only in Web Contexts) the ServletContext object.
${session.foo}
3)、内置的一些工具对象:
#execInfo : information about the template being processed.
#messages : methods for obtaining externalized messages inside variables expressions, in the same way as they would be obtained using #{…} syntax.
#uris : methods for escaping parts of URLs/URIs
#conversions : methods for executing the configured conversion service (if any).
#dates : methods for java.util.Date objects: formatting, component extraction, etc.
#calendars : analogous to #dates , but for java.util.Calendar objects.
#numbers : methods for formatting numeric objects.
#strings : methods for String objects: contains, startsWith, prepending/appending, etc.
#objects : methods for objects in general.
#bools : methods for boolean evaluation.
#arrays : methods for arrays.
#lists : methods for lists.
#sets : methods for sets.
#maps : methods for maps.
#aggregates : methods for creating aggregates on arrays or collections.
#ids : methods for dealing with id attributes that might be repeated (for example, as a result of an iteration).
(2)Selection Variable Expressions: *{...}:选择表达式:和${}在功能上是一样; 补充:配合 th:object="${session.user}:#只有作为全局变量使用的时候才是不一样的
eg: 用th:object从session里面取出user对象(即将取出来的对象赋值给Object),以后要用user对象的值,就可以在当前的div里面,
"*"号就代表刚才的th:object对象,然后直接获取对象的属性即可。
<div th:object="${session.user}">
<p>Name: <span th:text="*{firstName}">Sebastian</span>.</p>
<p>Surname: <span th:text="*{lastName}">Pepper</span>.</p>
<p>Nationality: <span th:text="*{nationality}">Saturn</span>.</p>
</div>
--以上方式等于如下方式$和*号功能是一样的,而且$和*可以混合使用
<div th:object="${session.user}">
<p>Name: <span th:text="*{firstName}">Sebastian</span>.</p>
<p>Surname: <span th:text="${session.user.lastName}">Pepper</span>.</p>
<p>Nationality: <span th:text="*{nationality}">Saturn</span>.</p>
</div>
(3)Message Expressions: #{...}:获取国际化内容 (4)Link URL Expressions: @{...}:定义URL;
@{/order/process(execId=${execId},execType='FAST')}
(5)Fragment Expressions: ~{...}:片段引用表达式
<div th:insert="~{commons :: main}">...</div>
2、Literals(字面量)
Text literals: 'one text' , 'Another one!' ,…
Number literals: 0 , 34 , 3.0 , 12.3 ,…
Boolean literals: true , false
Null literal: null
Literal tokens: one , sometext , main ,…
3、Text operations:(文本操作)
String concatenation: +
Literal substitutions: |The name is ${name}|
4、Arithmetic operations:(数学运算)
Binary operators: + , - , * , / , %
Minus sign (unary operator): -
5、Boolean operations:(布尔运算)
Binary operators: and , or
Boolean negation (unary operator): ! , not
6、Comparisons and equality:(比较运算)
Comparators: > , < , >= , <= ( gt , lt , ge , le )
Equality operators: == , != ( eq , ne )
7、Conditional operators:条件运算(三元运算符)
If-then: (if) ? (then)
If-then-else: (if) ? (then) : (else)
Default: (value) ?: (defaultvalue)
8、Special tokens(特殊操作):
No-Operation: _