thymeleaf学习

一.简单表达格式:   thymeleaf的官方参考文档

　　1.变量的表达式：${...}

　　2.选择变量表达式：*{...}

　　3.信息表达:#{...}

　　4.链接URL表达式:@{...}

二.字面值

　　1.文本文字：'one text', 'Another one!',…

　　2.文字数量：0, 34, 3.0, 12.3,…

　　3.布尔型常量：true, false

　　4.空的文字：null

　　5.文字标记：one, sometext, main,…

四：文本处理

　　1.字符串并置：+

　　2.文字替换：|The name is ${name}|

五.表达基本对象

　　1.#ctx:上下文对象

　　2.#vars:上下文变量

　　3.#locale:上下文语言环境

　　4.#httpServletRequest:(只有在Web上下文)HttpServletRequest对象

　　5.#httpSession:(只有在Web上下文)HttpSession对象。

用法：

<span th:text="${#locale.country}">US</span>.

六.实用表达对象　

• #dates: java.util的实用方法。对象:日期格式、组件提取等.
• #calendars: 类似于#日期,但对于java.util。日历对象
• #numbers: 格式化数字对象的实用方法。
• #strings:字符串对象的实用方法:包含startsWith,将/附加等。
• #objects: 实用方法的对象。
• #bools: 布尔评价的实用方法。
• #arrays: 数组的实用方法。
• #lists: list集合。
• #sets:set集合。
• #maps: map集合。
• #aggregates: 实用程序方法用于创建聚集在数组或集合.
• #messages: 实用程序方法获取外部信息内部变量表达式,以同样的方式,因为他们将获得使用# {…}语法
• #ids: 实用程序方法来处理可能重复的id属性(例如,由于迭代)。

  Dates
  
  #dates : utility methods for java.util.Date objects:
  /*
   * ======================================================================
   * See javadoc API for class org.thymeleaf.expression.Dates
   * ======================================================================
   */
  
  /*
   * Null-safe toString()
   */
  ${#strings.toString(obj)}                           // also array*, list* and set*
  
  /*
   * Format date with the standard locale format
   * Also works with arrays, lists or sets
   */
  ${#dates.format(date)}
  ${#dates.arrayFormat(datesArray)}
  ${#dates.listFormat(datesList)}
  ${#dates.setFormat(datesSet)}
  
  /*
   * Format date with the specified pattern
   * Also works with arrays, lists or sets
   */
  ${#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')}
  
  /*
   * Obtain date properties
   * Also works with arrays, lists or sets
   */
  ${#dates.day(date)}                    // also arrayDay(...), listDay(...), etc.
  ${#dates.month(date)}                  // also arrayMonth(...), listMonth(...), etc.
  ${#dates.monthName(date)}              // also arrayMonthName(...), listMonthName(...), etc.
  ${#dates.monthNameShort(date)}         // also arrayMonthNameShort(...), listMonthNameShort(...), etc.
  ${#dates.year(date)}                   // also arrayYear(...), listYear(...), etc.
  ${#dates.dayOfWeek(date)}              // also arrayDayOfWeek(...), listDayOfWeek(...), etc.
  ${#dates.dayOfWeekName(date)}          // also arrayDayOfWeekName(...), listDayOfWeekName(...), etc.
  ${#dates.dayOfWeekNameShort(date)}     // also arrayDayOfWeekNameShort(...), listDayOfWeekNameShort(...), etc.
  ${#dates.hour(date)}                   // also arrayHour(...), listHour(...), etc.
  ${#dates.minute(date)}                 // also arrayMinute(...), listMinute(...), etc.
  ${#dates.second(date)}                 // also arraySecond(...), listSecond(...), etc.
  ${#dates.millisecond(date)}            // also arrayMillisecond(...), listMillisecond(...), etc.
  
  /*
   * Create date (java.util.Date) objects from its components
   */
  ${#dates.create(year,month,day)}
  ${#dates.create(year,month,day,hour,minute)}
  ${#dates.create(year,month,day,hour,minute,second)}
  ${#dates.create(year,month,day,hour,minute,second,millisecond)}
  
  /*
   * Create a date (java.util.Date) object for the current date and time
   */
  ${#dates.createNow()}
  
  /*
   * Create a date (java.util.Date) object for the current date (time set to 00:00)
   */
  ${#dates.createToday()}
  Calendars
  
  #calendars : analogous to #dates, but for java.util.Calendar objects:
  /*
   * ======================================================================
   * See javadoc API for class org.thymeleaf.expression.Calendars
   * ======================================================================
   */
  
  /*
   * Format calendar with the standard locale format
   * Also works with arrays, lists or sets
   */
  ${#calendars.format(cal)}
  ${#calendars.arrayFormat(calArray)}
  ${#calendars.listFormat(calList)}
  ${#calendars.setFormat(calSet)}
  
  /*
   * Format calendar with the specified pattern
   * Also works with arrays, lists or sets
   */
  ${#calendars.format(cal, 'dd/MMM/yyyy HH:mm')}
  ${#calendars.arrayFormat(calArray, 'dd/MMM/yyyy HH:mm')}
  ${#calendars.listFormat(calList, 'dd/MMM/yyyy HH:mm')}
  ${#calendars.setFormat(calSet, 'dd/MMM/yyyy HH:mm')}
  
  /*
   * Obtain calendar properties
   * Also works with arrays, lists or sets
   */
  ${#calendars.day(date)}                // also arrayDay(...), listDay(...), etc.
  ${#calendars.month(date)}              // also arrayMonth(...), listMonth(...), etc.
  ${#calendars.monthName(date)}          // also arrayMonthName(...), listMonthName(...), etc.
  ${#calendars.monthNameShort(date)}     // also arrayMonthNameShort(...), listMonthNameShort(...), etc.
  ${#calendars.year(date)}               // also arrayYear(...), listYear(...), etc.
  ${#calendars.dayOfWeek(date)}          // also arrayDayOfWeek(...), listDayOfWeek(...), etc.
  ${#calendars.dayOfWeekName(date)}      // also arrayDayOfWeekName(...), listDayOfWeekName(...), etc.
  ${#calendars.dayOfWeekNameShort(date)} // also arrayDayOfWeekNameShort(...), listDayOfWeekNameShort(...), etc.
  ${#calendars.hour(date)}               // also arrayHour(...), listHour(...), etc.
  ${#calendars.minute(date)}             // also arrayMinute(...), listMinute(...), etc.
  ${#calendars.second(date)}             // also arraySecond(...), listSecond(...), etc.
  ${#calendars.millisecond(date)}        // also arrayMillisecond(...), listMillisecond(...), etc.
  
  /*
   * Create calendar (java.util.Calendar) objects from its components
   */
  ${#calendars.create(year,month,day)}
  ${#calendars.create(year,month,day,hour,minute)}
  ${#calendars.create(year,month,day,hour,minute,second)}
  ${#calendars.create(year,month,day,hour,minute,second,millisecond)}
  
  /*
   * Create a calendar (java.util.Calendar) object for the current date and time
   */
  ${#calendars.createNow()}
  
  /*
   * Create a calendar (java.util.Calendar) object for the current date (time set to 00:00)
   */
  ${#calendars.createToday()}
  Numbers
  
  #numbers : utility methods for number objects:
  /*
   * ======================================================================
   * See javadoc API for class org.thymeleaf.expression.Numbers
   * ======================================================================
   */
  
  /*
   * ==========================
   * Formatting integer numbers
   * ==========================
   */
  
  /* 
   * Set minimum integer digits.
   * Also works with arrays, lists or sets
   */
  ${#numbers.formatInteger(num,3)}
  ${#numbers.arrayFormatInteger(numArray,3)}
  ${#numbers.listFormatInteger(numList,3)}
  ${#numbers.setFormatInteger(numSet,3)}
  
  
  /* 
   * Set minimum integer digits and thousands separator: 
   * 'POINT', 'COMMA', 'NONE' or 'DEFAULT' (by locale).
   * Also works with arrays, lists or sets
   */
  ${#numbers.formatInteger(num,3,'POINT')}
  ${#numbers.arrayFormatInteger(numArray,3,'POINT')}
  ${#numbers.listFormatInteger(numList,3,'POINT')}
  ${#numbers.setFormatInteger(numSet,3,'POINT')}
  
  
  /*
   * ==========================
   * Formatting decimal numbers
   * ==========================
   */
  
  /*
   * Set minimum integer digits and (exact) decimal digits.
   * Also works with arrays, lists or sets
   */
  ${#numbers.formatDecimal(num,3,2)}
  ${#numbers.arrayFormatDecimal(numArray,3,2)}
  ${#numbers.listFormatDecimal(numList,3,2)}
  ${#numbers.setFormatDecimal(numSet,3,2)}
  
  /*
   * Set minimum integer digits and (exact) decimal digits, and also decimal separator.
   * Also works with arrays, lists or sets
   */
  ${#numbers.formatDecimal(num,3,2,'COMMA')}
  ${#numbers.arrayFormatDecimal(numArray,3,2,'COMMA')}
  ${#numbers.listFormatDecimal(numList,3,2,'COMMA')}
  ${#numbers.setFormatDecimal(numSet,3,2,'COMMA')}
  
  /*
   * Set minimum integer digits and (exact) decimal digits, and also thousands and 
   * decimal separator.
   * Also works with arrays, lists or sets
   */
  ${#numbers.formatDecimal(num,3,'POINT',2,'COMMA')}
  ${#numbers.arrayFormatDecimal(numArray,3,'POINT',2,'COMMA')}
  ${#numbers.listFormatDecimal(numList,3,'POINT',2,'COMMA')}
  ${#numbers.setFormatDecimal(numSet,3,'POINT',2,'COMMA')}
  
  
  
  /*
   * ==========================
   * Utility methods
   * ==========================
   */
  
  /*
   * Create a sequence (array) of integer numbers going
   * from x to y
   */
  ${#numbers.sequence(from,to)}
  ${#numbers.sequence(from,to,step)}
  Strings
  
  #strings : utility methods for String objects:
  /*
   * ======================================================================
   * See javadoc API for class org.thymeleaf.expression.Strings
   * ======================================================================
   */
  
  /*
   * Check whether a String is empty (or null). Performs a trim() operation before check
   * Also works with arrays, lists or sets
   */
  ${#strings.isEmpty(name)}
  ${#strings.arrayIsEmpty(nameArr)}
  ${#strings.listIsEmpty(nameList)}
  ${#strings.setIsEmpty(nameSet)}
  
  /*
   * Perform an 'isEmpty()' check on a string and return it if false, defaulting to
   * another specified string if true.
   * Also works with arrays, lists or sets
   */
  ${#strings.defaultString(text,default)}
  ${#strings.arrayDefaultString(textArr,default)}
  ${#strings.listDefaultString(textList,default)}
  ${#strings.setDefaultString(textSet,default)}
  
  /*
   * Check whether a fragment is contained in a String
   * Also works with arrays, lists or sets
   */
  ${#strings.contains(name,'ez')}                     // also array*, list* and set*
  ${#strings.containsIgnoreCase(name,'ez')}           // also array*, list* and set*
  
  /*
   * Check whether a String starts or ends with a fragment
   * Also works with arrays, lists or sets
   */
  ${#strings.startsWith(name,'Don')}                  // also array*, list* and set*
  ${#strings.endsWith(name,endingFragment)}           // also array*, list* and set*
  
  /*
   * Substring-related operations
   * Also works with arrays, lists or sets
   */
  ${#strings.indexOf(name,frag)}                      // also array*, list* and set*
  ${#strings.substring(name,3,5)}                     // also array*, list* and set*
  ${#strings.substringAfter(name,prefix)}             // also array*, list* and set*
  ${#strings.substringBefore(name,suffix)}            // also array*, list* and set*
  ${#strings.replace(name,'las','ler')}               // also array*, list* and set*
  
  /*
   * Append and prepend
   * Also works with arrays, lists or sets
   */
  ${#strings.prepend(str,prefix)}                     // also array*, list* and set*
  ${#strings.append(str,suffix)}                      // also array*, list* and set*
  
  /*
   * Change case
   * Also works with arrays, lists or sets
   */
  ${#strings.toUpperCase(name)}                       // also array*, list* and set*
  ${#strings.toLowerCase(name)}                       // also array*, list* and set*
  
  /*
   * Split and join
   */
  ${#strings.arrayJoin(namesArray,',')}
  ${#strings.listJoin(namesList,',')}
  ${#strings.setJoin(namesSet,',')}
  ${#strings.arraySplit(namesStr,',')}                // returns String[]
  ${#strings.listSplit(namesStr,',')}                 // returns List<String>
  ${#strings.setSplit(namesStr,',')}                  // returns Set<String>
  
  /*
   * Trim
   * Also works with arrays, lists or sets
   */
  ${#strings.trim(str)}                               // also array*, list* and set*
  
  /*
   * Compute length
   * Also works with arrays, lists or sets
   */
  ${#strings.length(str)}                             // also array*, list* and set*
  
  /*
   * Abbreviate text making it have a maximum size of n. If text is bigger, it
   * will be clipped and finished in "..."
   * Also works with arrays, lists or sets
   */
  ${#strings.abbreviate(str,10)}                      // also array*, list* and set*
  
  /*
   * Convert the first character to upper-case (and vice-versa)
   */
  ${#strings.capitalize(str)}                         // also array*, list* and set*
  ${#strings.unCapitalize(str)}                       // also array*, list* and set*
  
  /*
   * Convert the first character of every word to upper-case
   */
  ${#strings.capitalizeWords(str)}                    // also array*, list* and set*
  ${#strings.capitalizeWords(str,delimiters)}         // also array*, list* and set*
  
  /*
   * Escape the string
   */
  ${#strings.escapeXml(str)}                          // also array*, list* and set*
  ${#strings.escapeJava(str)}                         // also array*, list* and set*
  ${#strings.escapeJavaScript(str)}                   // also array*, list* and set*
  ${#strings.unescapeJava(str)}                       // also array*, list* and set*
  ${#strings.unescapeJavaScript(str)}                 // also array*, list* and set*
  
  /*
   * Null-safe comparison and concatenation
   */
  ${#strings.equals(str)}
  ${#strings.equalsIgnoreCase(str)}
  ${#strings.concat(str)}
  ${#strings.concatReplaceNulls(str)}
  
  /*
   * Random
   */
  ${#strings.randomAlphanumeric(count)}
  Objects
  
  #objects : utility methods for objects in general
  /*
   * ======================================================================
   * See javadoc API for class org.thymeleaf.expression.Objects
   * ======================================================================
   */
  
  /*
   * Return obj if it is not null, and default otherwise
   * Also works with arrays, lists or sets
   */
  ${#objects.nullSafe(obj,default)}
  ${#objects.arrayNullSafe(objArray,default)}
  ${#objects.listNullSafe(objList,default)}
  ${#objects.setNullSafe(objSet,default)}
  Booleans
  
  #bools : utility methods for boolean evaluation
  /*
   * ======================================================================
   * See javadoc API for class org.thymeleaf.expression.Bools
   * ======================================================================
   */
  
  /*
   * Evaluate a condition in the same way that it would be evaluated in a th:if tag
   * (see conditional evaluation chapter afterwards).
   * Also works with arrays, lists or sets
   */
  ${#bools.isTrue(obj)}
  ${#bools.arrayIsTrue(objArray)}
  ${#bools.listIsTrue(objList)}
  ${#bools.setIsTrue(objSet)}
  
  /*
   * Evaluate with negation
   * Also works with arrays, lists or sets
   */
  ${#bools.isFalse(cond)}
  ${#bools.arrayIsFalse(condArray)}
  ${#bools.listIsFalse(condList)}
  ${#bools.setIsFalse(condSet)}
  
  /*
   * Evaluate and apply AND operator
   * Receive an array, a list or a set as parameter
   */
  ${#bools.arrayAnd(condArray)}
  ${#bools.listAnd(condList)}
  ${#bools.setAnd(condSet)}
  
  /*
   * Evaluate and apply OR operator
   * Receive an array, a list or a set as parameter
   */
  ${#bools.arrayOr(condArray)}
  ${#bools.listOr(condList)}
  ${#bools.setOr(condSet)}
  Arrays
  
  #arrays : utility methods for arrays
  /*
   * ======================================================================
   * See javadoc API for class org.thymeleaf.expression.Arrays
   * ======================================================================
   */
  
  /*
   * Converts to array, trying to infer array component class.
   * Note that if resulting array is empty, or if the elements
   * of the target object are not all of the same class,
   * this method will return Object[].
   */
  ${#arrays.toArray(object)}
  
  /*
   * Convert to arrays of the specified component class.
   */
  ${#arrays.toStringArray(object)}
  ${#arrays.toIntegerArray(object)}
  ${#arrays.toLongArray(object)}
  ${#arrays.toDoubleArray(object)}
  ${#arrays.toFloatArray(object)}
  ${#arrays.toBooleanArray(object)}
  
  /*
   * Compute length
   */
  ${#arrays.length(array)}
  
  /*
   * Check whether array is empty
   */
  ${#arrays.isEmpty(array)}
  
  /*
   * Check if element or elements are contained in array
   */
  ${#arrays.contains(array, element)}
  ${#arrays.containsAll(array, elements)}
  Lists
  
  #lists : utility methods for lists
  /*
   * ======================================================================
   * See javadoc API for class org.thymeleaf.expression.Lists
   * ======================================================================
   */
  
  /*
   * Converts to list
   */
  ${#lists.toList(object)}
  
  /*
   * Compute size
   */
  ${#lists.size(list)}
  
  /*
   * Check whether list is empty
   */
  ${#lists.isEmpty(list)}
  
  /*
   * Check if element or elements are contained in list
   */
  ${#lists.contains(list, element)}
  ${#lists.containsAll(list, elements)}
  
  /*
   * Sort a copy of the given list. The members of the list must implement
   * comparable or you must define a comparator.
   */
  ${#lists.sort(list)}
  ${#lists.sort(list, comparator)}
  Sets
  
  #sets : utility methods for sets
  /*
   * ======================================================================
   * See javadoc API for class org.thymeleaf.expression.Sets
   * ======================================================================
   */
  
  /*
   * Converts to set
   */
  ${#sets.toSet(object)}
  
  /*
   * Compute size
   */
  ${#sets.size(set)}
  
  /*
   * Check whether set is empty
   */
  ${#sets.isEmpty(set)}
  
  /*
   * Check if element or elements are contained in set
   */
  ${#sets.contains(set, element)}
  ${#sets.containsAll(set, elements)}
  Maps
  
  #maps : utility methods for maps
  /*
   * ======================================================================
   * See javadoc API for class org.thymeleaf.expression.Maps
   * ======================================================================
   */
  
  /*
   * Compute size
   */
  ${#maps.size(map)}
  
  /*
   * Check whether map is empty
   */
  ${#maps.isEmpty(map)}
  
  /*
   * Check if key/s or value/s are contained in maps
   */
  ${#maps.containsKey(map, key)}
  ${#maps.containsAllKeys(map, keys)}
  ${#maps.containsValue(map, value)}
  ${#maps.containsAllValues(map, value)}
  Aggregates
  
  #aggregates : utility methods for creating aggregates on arrays or collections
  /*
   * ======================================================================
   * See javadoc API for class org.thymeleaf.expression.Aggregates
   * ======================================================================
   */
  
  /*
   * Compute sum. Returns null if array or collection is empty
   */
  ${#aggregates.sum(array)}
  ${#aggregates.sum(collection)}
  
  /*
   * Compute average. Returns null if array or collection is empty
   */
  ${#aggregates.avg(array)}
  ${#aggregates.avg(collection)}
  Messages
  
  #messages : utility methods for obtaining externalized messages inside variables expressions, in the same way as they would be obtained using #{...} syntax.
  /*
   * ======================================================================
   * See javadoc API for class org.thymeleaf.expression.Messages
   * ======================================================================
   */
  
  /*
   * Obtain externalized messages. Can receive a single key, a key plus arguments,
   * or an array/list/set of keys (in which case it will return an array/list/set of 
   * externalized messages).
   * If a message is not found, a default message (like '??msgKey??') is returned.
   */
  ${#messages.msg('msgKey')}
  ${#messages.msg('msgKey', param1)}
  ${#messages.msg('msgKey', param1, param2)}
  ${#messages.msg('msgKey', param1, param2, param3)}
  ${#messages.msgWithParams('msgKey', new Object[] {param1, param2, param3, param4})}
  ${#messages.arrayMsg(messageKeyArray)}
  ${#messages.listMsg(messageKeyList)}
  ${#messages.setMsg(messageKeySet)}
  
  /*
   * Obtain externalized messages or null. Null is returned instead of a default
   * message if a message for the specified key is not found.
   */
  ${#messages.msgOrNull('msgKey')}
  ${#messages.msgOrNull('msgKey', param1)}
  ${#messages.msgOrNull('msgKey', param1, param2)}
  ${#messages.msgOrNull('msgKey', param1, param2, param3)}
  ${#messages.msgOrNullWithParams('msgKey', new Object[] {param1, param2, param3, param4})}
  ${#messages.arrayMsgOrNull(messageKeyArray)}
  ${#messages.listMsgOrNull(messageKeyList)}
  ${#messages.setMsgOrNull(messageKeySet)}
  IDs
  
  #ids : utility methods for dealing with id attributes that might be repeated (for example, as a result of an iteration).
  /*
   * ======================================================================
   * See javadoc API for class org.thymeleaf.expression.Ids
   * ======================================================================
   */
  
  /*
   * Normally used in th:id attributes, for appending a counter to the id attribute value
   * so that it remains unique even when involved in an iteration process.
   */
  ${#ids.seq('someId')}
  
  /*
   * Normally used in th:for attributes in <label> tags, so that these labels can refer to Ids
   * generated by means if the #ids.seq(...) function.
   *
   * Depending on whether the <label> goes before or after the element with the #ids.seq(...)
   * function, the "next" (label goes before "seq") or the "prev" function (label goes after 
   * "seq") function should be called.
   */
  ${#ids.next('someId')}
  ${#ids.prev('someId')}

七.thymeleaf的$和*的区别:

<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>

这等同于如下方式：

<div>
  <p>Name: <span th:text="${session.user.firstName}">Sebastian</span>.</p>
  <p>Surname: <span th:text="${session.user.lastName}">Pepper</span>.</p>
  <p>Nationality: <span th:text="${session.user.nationality}">Saturn</span>.</p>
</div>

也可以混用,如下:

<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>

当一个对象的选择,选择的对象将也可用美元作为#对象表达变量表达式：

<div th:object="${session.user}">
  <p>Name: <span th:text="${#object.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>

如果没有执行对象选择,美元和星号语法是完全等价的:

<div>
  <p>Name: <span th:text="*{session.user.name}">Sebastian</span>.</p>
  <p>Surname: <span th:text="*{session.user.surname}">Pepper</span>.</p>
  <p>Nationality: <span th:text="*{session.user.nationality}">Saturn</span>.</p>
</div>