9）Thymeleaf ⼯具类对象表达式

╰半夏微凉° 2022-04-11 03:24 201阅读 0赞

**目录**

\#execInfo

URIs/URLs

Dates 日期工具类

Calendars 日期工具类

Numbers 数字工具类

Strings

Objects

Booleans

Arrays

Lists

Sets

Maps

Aggregates  聚合函数

IDs

--------------------

# \#execInfo #

\#execInfo：提供有关在 Thymeleaf 标准表达式内正在处理的模板的信息。

//See javadoc API for class org.thymeleaf.expression.ExecutionInfo

<body>
 #execInfo.templateName=[[${#execInfo.templateName}]]
 #execInfo.templateMode=[[${#execInfo.templateMode}]]
 #execInfo.processedTemplateName=[[${#execInfo.processedTemplateName}]]
 #execInfo.processedTemplateMode=[[${#execInfo.processedTemplateMode}]]
 #execInfo.templateNames=[[${#execInfo.templateNames}]]
 #execInfo.templateModes=[[${#execInfo.templateModes}]]
 #execInfo.templateStack=[[${#execInfo.templateStack}]]
 </body>

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dhbmdteDE5OTMzMjg_size_16_color_FFFFFF_t_70][]

# URIs/URLs #

\#uris：⽤于在 Thymeleaf 标准表达式中执⾏ URI / URL 操作（尤其是转义/取消转义）的⼯具对象。

// See javadoc API for class org.thymeleaf.expression.Uris

> Escape/Unescape as a URI/URL path（对 URI、URL 转码）
> 
> $\{\#uris.escapePath(uri)\}   //转码  
> $\{\#uris.escapePath(uri, encoding)\}  //指定编码转码
> 
> $\{\#uris.unescapePath(uri)\}  //解码  
> $\{\#uris.unescapePath(uri, encoding)\}  //指定编码解码

<body th:with="url='http://localhost/thymeleaf/user/home?u_id=9527&name=东方不败'">
 
 
 <div th:with="escapePath=${#uris.escapePath(url)}">
 被转码 url：[[${url}]]
 #uris.escapePath(uri) 转码后：[[${escapePath}]]
 #uris.unescapePath(uri) 解码后：[[${#uris.unescapePath(escapePath)}]]
 </div>
 </body>

![20181204164458617.png][]

> 类似的还有：
> 
> $\{\#uris.escapePathSegment(uri)\}  
> $\{\#uris.escapePathSegment(uri, encoding)\}  
> $\{\#uris.unescapePathSegment(uri)\}  
> $\{\#uris.unescapePathSegment(uri, encoding)\}
> 
> $\{\#uris.escapeFragmentId(uri)\}  
> $\{\#uris.escapeFragmentId(uri, encoding)\}  
> $\{\#uris.unescapeFragmentId(uri)\}  
> $\{\#uris.unescapeFragmentId(uri, encoding)\}
> 
> $\{\#uris.escapeQueryParam(uri)\}  
> $\{\#uris.escapeQueryParam(uri, encoding)\}  
> $\{\#uris.unescapeQueryParam(uri)\}  
> $\{\#uris.unescapeQueryParam(uri, encoding)\}

# Dates 日期工具类 #

\#dates：java.util.Date 对象的实⽤程序⽅法。//See javadoc API for class org.thymeleaf.expression.Dates

从后台输出的数据中如果含有日期，则需要进行格式化。

> Format date with the standard locale format ，Also works with arrays, lists or sets
> 
> （使用标准区域设置格式设置日期，也可以是日期数组、列表或集合————实际中这些用的少）  
> $\{\#dates.format(date)\}  
> $\{\#dates.arrayFormat(datesArray)\}  
> $\{\#dates.listFormat(datesList)\}  
> $\{\#dates.setFormat(datesSet)\}

> Format date with the ISO8601 format, Also works with arrays, lists or sets
> 
> （使用ISO8601格式格式化日期，也可以使用数组、列表或集合—————实际中这些用的少）
> 
> $\{\#dates.formatISO(date)\}  
> $\{\#dates.arrayFormatISO(datesArray)\}  
> $\{\#dates.listFormatISO(datesList)\}  
> $\{\#dates.setFormatISO(datesSet)\}

> Format date with the specified pattern, Also works with arrays, lists or sets
> 
> （用指定的模式格式化日期，也可以使用数组、列表或集合—————实际中通常都是用它）
> 
> $\{\#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')\}

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dhbmdteDE5OTMzMjg_size_16_color_FFFFFF_t_70 1][]

更多内容可参考官网：[https://www.thymeleaf.org/doc/tutorials/2.1/usingthymeleaf.html\#dates][https_www.thymeleaf.org_doc_tutorials_2.1_usingthymeleaf.html_dates]

# Calendars 日期工具类 #

\#calendars：类似于 \#dates，但对于 java.util.Calendar 对象，See javadoc API for class org.thymeleaf.expression.Calendars

可参考官网：[https://www.thymeleaf.org/doc/tutorials/2.1/usingthymeleaf.html\#calendars][https_www.thymeleaf.org_doc_tutorials_2.1_usingthymeleaf.html_calendars]

结果与 \#datas 完全一样。

# Numbers 数字工具类 #

\#numbers：数字对象的实⽤程序⽅法，See javadoc API for class org.thymeleaf.expression.Numbers

用于格式化数字。

>  Set minimum integer digits. Also works with arrays, lists or sets
> 
> （设置最小整数位数。也适用于数组、列表或集合）
> 
> 格式：$\{\#numbers.formatInteger(num,size)\}：num 表示被格式的数字，size 表示整数位最少保留几位。

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dhbmdteDE5OTMzMjg_size_16_color_FFFFFF_t_70 2][]

> Set minimum integer digits and thousands separator: 'POINT', 'COMMA', 'WHITESPACE', 'NONE' or 'DEFAULT' (bylocale). Also works with arrays, lists or sets
> 
> （设置最小整数位数和数以千计的分隔符：“点”、“逗号”、“空白”、“没有”或“默认”（字节环境）。也适用于数组、列表或集合）
> 
> 格式：$\{\#numbers.formatInteger(num,size,format)\}：num 表示被格式的数字，size 表示整数位最少保留几位，format 表示格式，有： 'POINT', 'COMMA', 'WHITESPACE', 'NONE' or 'DEFAULT'

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dhbmdteDE5OTMzMjg_size_16_color_FFFFFF_t_70 3][]

更多用法请参考官网：[https://www.thymeleaf.org/doc/tutorials/2.1/usingthymeleaf.html\#numbers][https_www.thymeleaf.org_doc_tutorials_2.1_usingthymeleaf.html_numbers]

/*
     * ==========================
     * 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 String ⼯具类，就是字符串工具类，这以前 JSP 中的 JSTL 也有这种功能，如下所示，从方法名称即可猜到用途。

官网地址：[https://www.thymeleaf.org/doc/tutorials/2.1/usingthymeleaf.html\#strings][https_www.thymeleaf.org_doc_tutorials_2.1_usingthymeleaf.html_strings]

/*
 * ======================================================================
 * See javadoc API for class org.thymeleaf.expression.Strings
 * ======================================================================
 */
 
 /*
 * Null-safe toString()
 */
 ${#strings.toString(obj)} // also array*, list* and set*
 
 /*
 * 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(first, second)}
 ${#strings.equalsIgnoreCase(first, second)}
 ${#strings.concat(values...)}
 ${#strings.concatReplaceNulls(nullValue, values...)}
 
 /*
 * 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  聚合函数 #

用于求和、求平均值等操作。

*  **\#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)}

官网地址：[https://www.thymeleaf.org/doc/tutorials/2.1/usingthymeleaf.html\#aggregates][https_www.thymeleaf.org_doc_tutorials_2.1_usingthymeleaf.html_aggregates]

# 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')}

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dhbmdteDE5OTMzMjg_size_16_color_FFFFFF_t_70]: /images/20220411/764fce224c7d4aff885e9bfe2f628ebf.png
[20181204164458617.png]: /images/20220411/30f7ddc0b7af4dde96fd98297ccb89ce.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dhbmdteDE5OTMzMjg_size_16_color_FFFFFF_t_70 1]: /images/20220411/566717f5653b4767a6ea18e5cd8ed288.png
[https_www.thymeleaf.org_doc_tutorials_2.1_usingthymeleaf.html_dates]: https://www.thymeleaf.org/doc/tutorials/2.1/usingthymeleaf.html#dates
[https_www.thymeleaf.org_doc_tutorials_2.1_usingthymeleaf.html_calendars]: https://www.thymeleaf.org/doc/tutorials/2.1/usingthymeleaf.html#calendars
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dhbmdteDE5OTMzMjg_size_16_color_FFFFFF_t_70 2]: /images/20220411/c10e83843ba94e999b76c13175b18544.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dhbmdteDE5OTMzMjg_size_16_color_FFFFFF_t_70 3]: /images/20220411/fe7b09a6964e421f8708fed693545b80.png
[https_www.thymeleaf.org_doc_tutorials_2.1_usingthymeleaf.html_numbers]: https://www.thymeleaf.org/doc/tutorials/2.1/usingthymeleaf.html#numbers
[https_www.thymeleaf.org_doc_tutorials_2.1_usingthymeleaf.html_strings]: https://www.thymeleaf.org/doc/tutorials/2.1/usingthymeleaf.html#strings
[https_www.thymeleaf.org_doc_tutorials_2.1_usingthymeleaf.html_aggregates]: https://www.thymeleaf.org/doc/tutorials/2.1/usingthymeleaf.html#aggregates