SpringBoot学习笔记-Web开发
Table of Contents
1 SpringBoot与Web开发
1.1 SpringBoot对静态资源的映射规则
- 引入前端框架资源, 所有
/webjars/**
,都去classpath:/META-INF/resources/webjars
找资源
@Override public void addResourceHandlers(ResourceHandlerRegistry registry) { if (!this.resourceProperties.isAddMappings()) { logger.debug("Default resource handling disabled"); return; } Duration cachePeriod = this.resourceProperties.getCache().getPeriod(); CacheControl cacheControl = this.resourceProperties.getCache() .getCachecontrol().toHttpCacheControl(); if (!registry.hasMappingForPattern("/webjars/**")) { customizeResourceHandlerRegistration(registry .addResourceHandler("/webjars/**") .addResourceLocations("classpath:/META-INF/resources/webjars/") .setCachePeriod(getSeconds(cachePeriod)) .setCacheControl(cacheControl)); } String staticPathPattern = this.mvcProperties.getStaticPathPattern(); if (!registry.hasMappingForPattern(staticPathPattern)) { customizeResourceHandlerRegistration( registry.addResourceHandler(staticPathPattern) .addResourceLocations(getResourceLocations( this.resourceProperties.getStaticLocations())) .setCachePeriod(getSeconds(cachePeriod)) .setCacheControl(cacheControl)); } }
- 引入自己的前端页面资源, SpringBoot提供一下静态资源存放的文件夹
classpath: /META-INF/resources/
classpath: /resources/
classpath: /static/
classpath: /public/
/
: 当前页面的根路径
- 配置静态资源路径
spring: resources: static-locations: classpath:/hello, classpath:/test/
1.2 模板引擎
- 常用的模板引擎
- JSP
- Velocity
- Freemarker
- Thymeleaf
- 模板引擎的原理
- SpringBoot推荐使用
Thymeleaf
模板引擎
1.2.1 引入Thymeleaf
<!-- 引入Thymeleaf模板引擎 --> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-thymeleaf</artifactId> </dependency>
- 切换为
Thymeleaf3
版本
<!-- 布局功能的支持程序 thymeleaf3主程序 layout2以上版本 --> <properties> <thymeleaf.version>3.0.2.RELEASE</thymeleaf.version> <thymeleaf-layout-dialect.veresion>2.1.1</thymeleaf-layout-dialect.veresion> </properties>
1.2.2 Thymeleaf使用
- 导入thymeleaf的名称空间
<html xmlns:th="http://www.thymeleaf.org">
- 使用案例
// 查出一些数据,在页面展示 @RequestMapping("/success") public String success(Map<String, Object> map) { map.put("hello", "你好"); return "success"; }
<!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指定的值--> <div th:text="${hello}">这是显示欢迎信息</div> </body> </html>
1.2.3 Thymeleaf语法规则
th:text
: 改变当前元素的文本内容.th:任意html属性
: 来替换原生html属性的值.
- 标准表达式语法
Simple expressions:(表达式语法) 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. ${session.foo} 3)、内置的一些工具对象: #execInfo : information about the template being processed. #messages : methods for obtaining externalized messages inside variables expressions, in the same way as they would be obtained using #{…} syntax. #uris : methods for escaping parts of URLs/URIs #conversions : methods for executing the configured conversion service (if any). #dates : methods for java.util.Date objects: formatting, component extraction, etc. #calendars : analogous to #dates , but for java.util.Calendar objects. #numbers : methods for formatting numeric objects. #strings : methods for String objects: contains, startsWith, prepending/appending, etc. #objects : methods for objects in general. #bools : methods for boolean evaluation. #arrays : methods for arrays. #lists : methods for lists. #sets : methods for sets. #maps : methods for maps. #aggregates : methods for creating aggregates on arrays or collections. #ids : methods for dealing with id attributes that might be repeated (for example, as a result of an iteration). Selection Variable Expressions: *{...}:选择表达式:和${}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> Message Expressions: #{...}:获取国际化内容 Link URL Expressions: @{...}:定义URL; @{/order/process(execId=${execId},execType='FAST')} 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: