一些常见的模板引擎

JSP、Velocity、Freemarker、Thymeleaf

SpringBoot推荐的Thymeleaf,语法更简单,功能更强大。

SpringBoot 引入 thymeleaf

pom文件中添加依赖

        <!--引入thymeleaf模块引擎-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-thymeleaf</artifactId>
        </dependency>

thymeleaf官网

SpringBoot 使用 thymeleaf

查看SpringBoot自动配置源码

@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";

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 :在HTML文件的<html>标签中添加属性:xmlns:th="http://www.thymeleaf.org"

<html lang="en" xmlns:th="http://www.thymeleaf.org">

2、编写Controller跳转到页面

    /**
     * @return 跳转到classpath:/templates/success.html
     */
    @RequestMapping("/success")
    public String success(Map<String,Object> map){
        map.put("who","moti");
        return "success";
    }

3、编写html文件

<!DOCTYPE html>
<html lang="en" xmlns:th="http://www.thymeleaf.org">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
    <!--th:text 将div里面的文本内容设置为 -->
    <h1>欢迎你,<span th:text="${who}"></span>!</h1>
</body>
</html>

thymeleaf 语法规则

1、标签优先级

  • 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

2、表达式

  • 2.1 Simple expressions(简单表达式):
    • Variable Expressions: ${…} 变量表达式
    1. 获取对象的属性、调用方法
    2. 使用内置的基本对象
    3. 使用内置的一些工具对象
    # 内置基本对象
                #ctx : the context object.
                #vars: the context variables.
                #locale : the context locale.
                #request : (only in Web Contexts) the HttpServletRequest object.          
                #response : (only in Web Contexts) the HttpServletResponse object.             
                #session : (only in Web Contexts) the HttpSession object.             
                #servletContext : (only in Web Contexts) the ServletContext object.
    # 内置的一些工具对象 
                execInfo : information about the template being processed.
                messages : methods for obtaining externalized messages inside variables expressions, in the same way as they would be obtained using #{…} syntax.
                uris : methods for escaping parts of URLs/URIs
                conversions : methods for executing the configured conversion service (if any).
                dates : methods for java.util.Date objects: formatting, component extraction, etc.
                calendars : analogous to #dates , but for java.util.Calendar objects.
                numbers : methods for formatting numeric objects.
                strings : methods for String objects: contains, startsWith, prepending/appending, etc.
                objects : methods for objects in general.
                bools : methods for boolean evaluation.
                arrays : methods for arrays.
                lists : methods for lists.
                sets : methods for sets.
                maps : methods for maps.
                aggregates : methods for creating aggregates on arrays or collections.
                ids : methods for dealing with id attributes that might be repeated (for example, as a result of an iteration).
    • Selection Variable Expressions: *{…} 选择变量表达式 :和${}在功能上是一样

    补充:配合 th:object="${session.user}

    <div th:object="${session.user}">
        <p>Name: <span th:text="*{userName}">Sebastian</span>.</p>
        <p>Age: <span th:text="*{age}">Pepper</span>.</p>
        <p>Sex: <span th:text="*{sex}">Saturn</span>.</p>
    </div>
    • Message Expressions: #{…} 消息表达式 :获取国际化内容
    <h1 th:text="#{login.tip}">Please sign in</h1>
    • Link URL Expressions: @{…} 链接URL表达式 :定义URL
    @{/order/process(execId=${execId},execType='FAST')}
    • Fragment Expressions: ~{…} 片段表达式
    <div th:insert="~{commons :: main}">...</div>

  • 2.2 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 ,…

  • 2.3 Text operations(文本操作)
  •      String concatenation: +
         Literal substitutions: |The name is ${name}|

  • 2.4 Arithmetic operations(数学运算)
  • Binary operators: + , - , * , / , %
    Minus sign (unary operator): -

  • 2.5 Boolean operations(布尔运算)
  • Binary operators: and , or
    Boolean negation (unary operator): ! , not

  • 2.6 Comparisons and equality(比较运算)
  • Comparators: > , < , >= , <= ( gt , lt , ge , le )
    Equality operators: == , != ( eq , ne )

  • 2.7 Conditional operators 条件运算(三元运算符)
  • If-then: (if) ? (then)
    If-then-else: (if) ? (then) : (else)
    Default: (value) ?: (defaultvalue)

  • 2.8 Special tokens
  • No-Operation: _ 
    最后修改日期:2020-07-12

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