django - filter template

django- template filter

The role of the filter

• Django back to return to the data template, for processing

Filter syntax

Value | Filter: Parameters

Common filter templates, built-in filter defaultfilters.pycan be viewed

• date
  • date : 'Y-m-d H:i:s'
• length: get the length
• length_is: Analyzing length
• random: returns a random element, a filtered list of tuples or
• default: Set Default
• filesizeformat: Format File Size

Custom filters (focus)

• In one project 应用under a new templatetagspackage
• In templatetagscase a new packetextra_filter.py
• In extra_filter.pycustomize your own filters

from django.template.library import Library
register = Library()

@register.filter(is_safe=True)
def ext(value, arg=None):
   exts = ["doc", "docx", "exe", "pdf", "ppt", "rar", "txt", "xlsx", "zip"]
   return value if value in exts else "unknow"

• In the settings.pyactivationtemplatetags

    INSTALLED_APPS = [
        ....
        'resource.templatetags',
    ]

• In the template page using filters, add loadlabel
  {% load extra_filter %}
• Matching is completed, the normal use of a custom filter