資訊專欄INFORMATION COLUMN
摘要：目前最新版本作為官方推薦模板引擎，而且支持純瀏覽器展現模板表達式在脫離運行環境下不污染結構是時候了解一番了。當前數目，從開始。
Thymeleaf 目前最新版本3.0
Thymeleaf作為Spring-Boot官方推薦模板引擎，而且支持純HTML瀏覽器展現(模板表達式在脫離運行環境下不污染html結構).是時候了解一番了。
與Spring集成
org.thymeleaf thymeleaf-spring4 3.0.0.RELEASE
與Spring-Boot集成：
org.springframework.boot spring-boot-starter-thymeleaf
在Spring中進行配置：
@Configuration
@EnableWebMvc
@ComponentScan("com.thymeleafexamples")
public class ThymeleafConfig extends WebMvcConfigurerAdapter implements ApplicationContextAware {
private ApplicationContext applicationContext;
public void setApplicationContext(ApplicationContext applicationContext) {
this.applicationContext = applicationContext;
}
@Bean
public ViewResolver viewResolver() {
ThymeleafViewResolver resolver = new ThymeleafViewResolver();
resolver.setTemplateEngine(templateEngine());
resolver.setCharacterEncoding("UTF-8");
return resolver;
}
@Bean
public TemplateEngine templateEngine() {
SpringTemplateEngine engine = new SpringTemplateEngine();
engine.setEnableSpringELCompiler(true);
engine.setTemplateResolver(templateResolver());
return engine;
}
private ITemplateResolver templateResolver() {
SpringResourceTemplateResolver resolver = new SpringResourceTemplateResolver();
resolver.setApplicationContext(applicationContext);
resolver.setPrefix("/WEB-INF/templates/");
resolver.setTemplateMode(TemplateMode.HTML);
return resolver;
}
}
在Spring-Boot中只需如下配置：
#thymeleaf start spring.thymeleaf.mode=HTML5 spring.thymeleaf.encoding=UTF-8 spring.thymeleaf.content-type=text/html #開發時關閉緩存,不然沒法看到實時頁面 spring.thymeleaf.cache=false #thymeleaf end
具體可以配置的參數可以查看 org.springframework.boot.autoconfigure.thymeleaf.ThymeleafProperties這個類,上面的配置實際上就是注入到該類中的屬性值.
基本語法
hello
3333
表達式
Variable Expressions: ${...}
Selection Variable Expressions: *{...}
Message Expressions: #{...}
Link URL Expressions: @{...}
Fragment Expressions: ~{...}
字符串操作:
String concatenation: +
Literal substitutions: |The name is ${name}|
條件操作：
If-then: (if) ? (then)
If-then-else: (if) ? (then) : (else)
Default: (value) ?: (defaultvalue)
No-Operation: _
如："User is of type " + (${user.isAdmin()} ? "Administrator" : (${user.type} ?: "Unknown"))
1、獲取變量值
3333
可以看出獲取變量值用$符號,對于javaBean的話使用變量名.屬性名方式獲取,這點和EL表達式一樣.另外$表達式只能寫在th標簽內部,不然不會生效
#{}是國際化支持取值的符號
注意:th:text與th:utext的區別，輸出中文時應該使用th:utext
${..}實際語法是:OGNL(非web),SpEL(web) ,支持的內置變量
便捷部分
${x} will return a variable x stored into the Thymeleaf context or as a request attribute.
${param.x} will return a request parameter called x (which might be multivalued).
${session.x} will return a session attribute called x.
${application.x} will return a servlet context attribute called x.
基本的
#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.
工具對象
#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).
工具對象的使用方式見：http://www.thymeleaf.org/doc/...， 以下僅僅舉幾個例子
${#dates.format(date, "dd/MMM/yyyy HH:mm")}
${#dates.arrayFormat(datesArray, "dd/MMM/yyyy HH:mm")}
${#dates.listFormat(datesList, "dd/MMM/yyyy HH:mm")}
${#dates.setFormat(datesSet, "dd/MMM/yyyy HH:mm")}
${#dates.createNow()}
${#dates.createToday()} //time set to 00:00
${#strings.isEmpty(name)} //Check whether a String is empty (or null)
${#strings.arrayIsEmpty(nameArr)}
${#strings.listIsEmpty(nameList)}
${#strings.setIsEmpty(nameSet)}
${#strings.startsWith(name,"Don")} // also array*, list* and set*
${#strings.endsWith(name,endingFragment)} // also array*, list* and set*
${#strings.length(str)}
${#strings.equals(str)}
${#strings.equalsIgnoreCase(str)}
${#strings.concat(str)}
${#strings.concatReplaceNulls(str)}
用*{...} 選擇對象里的變量，如
字面量//等價于Name: Sebastian.
Surname: Pepper.
Nationality: Saturn.
Name: Sebastian.
Surname: Pepper.
Nationality: Saturn.
Text literals: "one text", "Another one!",…
Number literals: 0, 34, 3.0, 12.3,…
Boolean literals: true, false
Null literal: null
字符串一般需要包圍在"單引號內，但也有幾種變通方式
...//Which is equivalent to:
定義模板本地變量
The name of the first person is Julius Caesar.
The name of the first person is Julius Caesar.
But the name of the second person is Marcus Antonius.
2.引入URL
Thymeleaf對于URL的處理是通過語法@{…}來處理的
絕對路徑 相對路徑 Content路徑,默認訪問static下的css文件夾
類似的標簽有:th:href和th:src
view view view view view
Server root relative URLs
An additional syntax can be used to create server-root-relative (instead of context-root-relative) URLs in order to link to different contexts in the same server. These URLs will be specified like @{~/path/to/something}
3、運算符
在表達式中可以使用各類算術運算符，例如+, -, *, /, %
th:with="isEven=(${prodStat.count} % 2 == 0)"
邏輯運算符>, <, >=, <=，==,!= (gt, lt, ge, le,eq,ne)都可以使用，唯一需要注意的是使用<,>時需要用它的HTML轉義符：
th:if="${prodStat.count} > 1"
th:text=""Execution mode is " + ( (${execMode} == "dev")? "Development" : "Production")"
布爾運算符: and or not/!
4.條件
if/unless
Thymeleaf中使用th:if和th:unless屬性進行條件判斷，標簽只有在th:if中條件成立時才顯示,th:unless于th:if恰好相反，只有表達式中的條件不成立，才會顯示其內容。
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Switch
Thymeleaf同樣支持多路選擇Switch結構,默認屬性default可以用*表示:
