java Thymeleaf th:each 用 th:if 过滤
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Thymeleaf th:each filtered with th:if
提问by Faraj Farook
I need to iterate and create <span>elements for each of the componentin the componentsarray which has the nameof 'MATERIAL'
我需要迭代，并创建<span>针对每个元件component中components，其具有阵列name的'MATERIAL'
My code is as below
我的代码如下
<span th:each="component : ${body.components}"
th:object="${component}">
<button th:if="*{name} == 'MATERIAL'"
th:text="*{title}"></button>
</span>
This code works all good until this produces a set of empty <span>elements if the nameis not equal to 'MATERIAL'. I don't want this empty <span>elements to get created.
<span>如果name不等于 ，则此代码运行良好，直到产生一组空元素'MATERIAL'。我不希望<span>创建这个空元素。
I also tried the below
我也试过下面的
<span th:each="component : ${body.components}"
th:object="${component}"
th:if="*{name} == 'MATERIAL'">
<button th:text="*{title}"></button>
</span>
This results in empty output and doesn't print anything at all. Can someone please help me on this.
这会导致空输出并且根本不打印任何内容。有人可以帮我解决这个问题。
回答by tmarwen
You should reference the iteration item property directly using a dot (.) sign instead of going through an SpEL expression evalution (*{name}) inside your html element:
您应该使用点 ( .) 符号直接引用迭代项属性，而不是通过*{name}您内部的 SpEL 表达式求值 ( )html元素：
<span th:each="component : ${body.components}"
th:object="${component}"
th:if="${component.name} == 'MATERIAL'">
<button th:text="*{title}"></button>
</span>
