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模板过滤器 - default


示例

编写颜色名称,但如果值为为空则写“nocolor”

{% for x in colors %}
  <h1>{{ x|default:"nocolor" }}</h1>
{% endfor %}
运行示例 »

定义和用法

The default 过滤器允许您指定一个默认值,如果该值计算结果为 False 则使用该默认值。

计算结果为 False 的值是

  • 空字符串 ""
  • 任何数字 0
  • 任何空对象 [], (), {}, set(), range(0)
  • None
  • False

语法

{{ value|default:defaultvalue }}

模板过滤器通过使用管道 | 字符后跟过滤器的名称来定义。

参数通过使用冒号 : 字符后跟参数值来定义。


参数

描述
defaultvalue 必需。如果该值为 False,则返回该值。

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