TMBlog技术文章分享

一.简单表达格式:
　　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,…
三：文本处理

　　1.字符串并置：+

　　2.文字替换：|The name is ${name}|

四.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 : 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‘)}

六.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>