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firstof 模板标签


示例

返回三个变量(xyz)中第一个非空或非假的变量的值。

<h1>
{% firstof x y z %}
</h1>
运行示例 »

定义和用法

firstof 标签返回第一个不是空变量的参数。

空变量可以是空字符串 ""、零数字 0 或布尔值 false

示例

第一个值现在为空,看看会发生什么

<h1>
{% firstof x y z %}
</h1>
运行示例 »

语法

{% firstof var1 var2 var3 etc. %}

参数

描述
var1 var2 var3 等 任何类型的变量。返回第一个非空、非 0 或非假的变量。如果所有变量都为空,则不返回任何内容。

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