表达式元素语法：
| Syntax | Description(注：中文部分为个人理解) |
|---|---|
| <attribute> | Evaluates to the value of attribute.ToString() if it exists else empty string. 调用attribute.ToString()方法，若attribute不存在，则显示空字符串 |
| <i>, <i0> | The iteration number indexed from one and from zero, respectively, when referenced within a template being applied to an attribute or attributes. 集合的当前索引值，<i>从1开始计算，<i0>从0开始计算，如果当前集合为null，则显示空字符串 |
| <attribute.property> | Looks for property of attribute as a property (C#), then accessor methods like getProperty() or isProperty(). If that fails, StringTemplate looks for a raw field of the attribute called property. Evaluates to the empty string if no such property is found. 获取attribute的property属性值,如user.Name |
| <attribute.(expr)> | Indirect property lookup. Same as attribute.property except use the value of expr as the property_ name. Evaluates to the empty string if no such property is found. 同上，区别在于字段为保留字的情况下使用，如user.("Name") |
| <multi-valued-attribute> | Concatenation of ToString() invoked on each element. If multi-valued-attribute is missing his evaluates to the empty string. 调用集合中所有非null元素的ToString方法，再把它们连接起来 |
| <multi-valued-attribute; separator=expr> | Concatenation of ToString() invoked on each element separated by expr. 同上，区别在于，连接的时候在相邻的两个元素之间使用了分隔符 |
| <[mine, yours]> | Creates a new multi-valued attribute (a list) with elements of mine first then all of yours. 把mine和yours合并成新的集合，不限于mine、yours两个元素。对于不同类型的mine和yours，都会转换成数组形式。其他用法同上 |
| <template(argument-list)> | Include template. The argument-list is a list of attribute assignments where each assignment is of the form arg-of-template=expr where expr is evaluated in the context of the surrounding template not of the invoked template. 调用模板，传递参数(若有参数)，template为模板名称，如template() |
| <(expr)(argument-list)> | Include template whose name is computed via expr. The argument-list is a list of attribute assignments where each assignment is of the form attribute=expr. Example $(whichFormat)()$ looks up whichFormat's value and uses that as template name. Can also apply an indirect template to an attribute. 同上，区别在于模板名称为关键字的时候，如("template")() |
| <attribute:template(argument-list)> | Apply template to attribute. The optional argument-list is evaluated before application so that you can set attributes referenced within template. The default attribute it is set to the value of attribute. If attribute is multi-valued, then it is set to each element in turn and template is invoked n times where n is the number of values in attribute. Example: $name:bold() applies bold() to name's value. 这是一种循环语法，对集合中每一个元素都应用template模板(若模板有参数则传递参数) |
| <attribute:(expr)(argument-list)> | Apply a template, whose name is computed from expr, to each value of attribute. Example $data:(name)()$ looks up name's value and uses that as template name to apply to data. 同上，区别在于模板名称为关键字的时候 |
| <attribute:t1(argument-list): ... :tN(argument-list)> | Apply multiple templates in order from left to right. The result of a template application upon a multi-valued attribute is another multi-valued attribute. The overall expression evaluates to the concatenation of all elements of the final multi-valued attribute resulting from templateN's application. 同<attribute:template(argument-list)>，区别在于，对集合中每一个元素都按从左到右的顺序应用了多个模板 |
| <attribute:{anonymous-template}> | Apply an anonymous template to each element of attribute. The iterated it atribute is set automatically. 匿名模板，即内联式的，跟匿名委托有些类似，这是一种循环语法，集合的当前元素名称自动设置为it |
| <attribute:{argument-name_ | _anonymous-template}> | Apply an anonymous template to each element of attribute. Set the argument-name to the iterated value and also set it. 同上，区别在于，手动设置集合的当前元素名称 |
| <a1,a2,...,aN:{argument-list_ | _anonymous-template}> | Parallel list iteration. March through the values of the attributes a1..aN, setting the values to the arguments in argument-list in the same order. Apply the anonymous template. There is no defined it value unless inherited from an enclosing scope. 多个参数的匿名模板，必须自定义每个集合的当前元素名称 |
| <attribute:t1(),t2(),...,tN()> | Apply an alternating list of templates to the elements of attribute. The template names may include argument lists. 交替调用模板，并应用到attribute如：$list:style1():style2:style3()$, 对第一个元素应用style1，第二个元素应用style2，第三个元素应用style3，依此类推 |
| <first(attr)> | The first or only element of attr. You can combine operations to say things like first(rest(names)) to get second element. 取得集合的第一个元素 |
| <last(attr)> | The last or only element of attr. 取得集合的最后一个元素 |
| <rest(attr)> | All but the first element of attr. Returns nothing if $attr$ a single valued. 取得集合中除第一个元素之外的所有元素，如果attribute不是集合，则显示空字符串 |
| <trunc(attr)> | returns all but last element 取得集合中除最后一个元素之外的所有元素，其他同上 |
| <strip(attr)> | Returns an iterator that skips any null values in $attr$. strip(x) =x when x is a single-valued attribute. 取得集合中所有不为null的元素，如果attribute不是集合，则显示attr的值 |
| <length(attr)> | Return an integer indicating how many elements in length $attr$ is. Single valued attributes return 1. Strings are not special; i.e., length("foo") is 1 meaning "1 attribute". Nulls are counted in lists so a list of 300 nulls is length 300. If you don't want to count nulls, use length(strip(list)). 取得集合的元素个数，即集合的长度 |
| \$ or \< | escaped delimiter prevents $ or < from starting an attribute expression and results in that single character. 对美元号$或尖括号<进行转义，当它们作为表达式分隔符的时候。默认为$...$，可以设置成一对尖括号<...> |
| <\ >, <\n>, <\t>, <\r> | special character(s): space, newline, tab, carriage return. Can have multiple in single <...> expression. 要在表达式中使用空格、换行符、制表符、回车符时，必须对它们进行转义，如输出换行符：<\n>， 也可以在单行表达式<...>里输出多个,如：<\n\r\t> |
| <\uXXXX> | Unicode character(s). Can have multiple in single <...> expression. Unicode字符，如<\u5555>，也可以在单行表达式<...>输出多个,如：<\u56E7\u6708> |
| <! comment !>, $! comment !$ | Comments, ignored by StringTemplate. 注释，分隔符与默认表达式分隔符一致，支持多行注释 |
条件声明：
| Syntax | Description |
|---|---|
| <if(attribute)>subtemplate <else>subtemplate2 <endif> | If attribute has a value or is a boolean object that evaluates to true, include subtemplate else include subtemplate2. These conditionals may be nested. 如果属性有值或者属性为bool值true，则表示达成条件，调用subtemplate模板，否则调用subtemplate2模板，这些条件可以嵌套 |
| <if(x)>subtemplate <elseif(y)>subtemplate2 <elseif(z)>subtemplate3 <else>subtemplate4 <endif> | First attribute that has a value or is a boolean object that evaluates to true, include that subtemplate. These conditionals may be nested. |
| <if(!attribute)>subtemplate<endif> | If attribute has no value or is a bool object that evaluates to false, include subtemplate. These conditionals may be nested. |
保留字：
不要使用这些保留字作为属性名称或模板名称(模板组、模板组接口不在此列)
| default first group if | implements interface last length | optional rest strip super | trunc else endif elseif |
样式真是无语啊，还是不会用这博客！
本文地址：http://www.cnblogs.com/lwme/archive/2010/04/29/1724186.html
英文来自：http://www.antlr.org/wiki/display/ST/StringTemplate+cheat+sheet