6、模板引擎
JSP、Velocity、Freemarker、Thymeleaf
对于模板引擎,SpringBoot推荐的Thymeleaf;
1)、引入
springboot官方文档
坐标:
<!--模板引擎--> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-thymeleaf</artifactId> </dependency>
切换其版本:
均在GitHub中进行查看
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>
2)、使用
使用规则:
ThymeleafProperties.java
@ConfigurationProperties( prefix = "spring.thymeleaf" ) public class ThymeleafProperties { private static final Charset DEFAULT_ENCODING; public static final String DEFAULT_PREFIX = "classpath:/templates/"; public static final String DEFAULT_SUFFIX = ".html"; private boolean checkTemplate = true; private boolean checkTemplateLocation = true; private String prefix = "classpath:/templates/"; private String suffix = ".html";
只要我们把HTML页面放在classpath:/templates/,thymeleaf就能自动渲染;
测试:
@Controller public class TestController { @RequestMapping("/test") public String testThymelea(){ //classpath:/templates/th.html return "th"; } }
静态文件
测试结果:
使用案例:
导入命名空间,有提示作用
<html lang="en" xmlns:th="http://www.thymeleaf.org">
语法:
<body> th页面! th页面! <!--th:text 将div里面的文本内容设置为 --> <div th:text="${th}">th</div> </body>
关于导入命名空间之后还没有提示:在进行重启
语法规则:
th:text;改变当前元素里面的文本内容;
<div th:id="" th:class=""></div>
文档的:位置
2)、表达式?
文档的位置
Simple expressions:(表达式语法) a. 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. ${session.foo} 3)、内置的一些工具对象: #execInfo : information about the template being processed. #messages : methods for obtaining externalized messages inside variables expressions, # in the same way as they would be obtained using #{…} syntax. #uris : methods for escaping parts of URLs/URIs #conversions : methods for executing the configured conversion service (if any). #dates : methods for java.util.Date objects: formatting, component extraction, etc. #calendars : analogous to #dates , but for java.util.Calendar objects. #numbers : methods for formatting numeric objects. #strings : methods for String objects: contains, startsWith, prepending/appending, etc. #objects : methods for objects in general. #bools : methods for boolean evaluation. #arrays : methods for arrays. #lists : methods for lists. #sets : methods for sets. #maps : methods for maps. #aggregates : methods for creating aggregates on arrays or collections. #ids : methods for dealing with id attributes that might be repeated (for example, as a result of an iteration). b. Selection Variable Expressions: *{...}:选择表达式:和${}在功能上是一样; 补充:配合 th:object="${session.user}: <div th:object="${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> c. Message Expressions: #{...}:获取国际化内容 d. Link URL Expressions: @{...}:定义URL; @{/order/process(execId=${execId},execType='FAST')} f. Fragment Expressions: ~{...}:片段引用表达式 <div th:insert="~{commons :: main}">...</div> 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 ,… Text operations:(文本操作) String concatenation: + Literal substitutions: |The name is ${name}| Arithmetic operations:(数学运算) Binary operators: + , - , * , / , % Minus sign (unary operator): - Boolean operations:(布尔运算) Binary operators: and , or Boolean negation (unary operator): ! , not Comparisons and equality:(比较运算) Comparators: > , < , >= , <= ( gt , lt , ge , le ) Equality operators: == , != ( eq , ne ) Conditional operators:条件运算(三元运算符) If-then: (if) ? (then) If-then-else: (if) ? (then) : (else) Default: (value) ?: (defaultvalue)Special tokens: No-Operation: _
b补充
测试:
<div th:text="${th}"></div> <div th:utext="${th}"></div> <!--每次遍历都会生成当前这个标签 --> <p th:text="${th}" th:each="th:${th1}"></p>
@RequestMapping("/test") public String testThymelea(Map<Object,Object> map){ map.put("th","<h2>helloword</h2>"); String [] t = {"a","b","c"}; map.put("th1",t); return "th"; }