Django过滤器与自定义标签

小灰灰 2022-04-23 21:22 199阅读 0赞

Django自定义标签

\{ \{变量\}\}

\{%标签%\}

| 过滤符

# 1、创建APP #

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80NDIzOTQ1NA_size_16_color_FFFFFF_t_70][]

# 2、在APP当中创建templatetags 包 #

![20190409163316365.png][]

# 3、在templatetags 目录下创建过滤器文件 #

## (1)、实例化模板库。 ##

注意：实例必须叫register

from django import template
    
    from Student.models import Students
    register = template.Library()
    
    def dosomething(value):
        return value.upper()
    
    register.filter('replaceUper',dosomething)
    
    @register.filter('replaceLower')
    def dosomething1(value):
        return value.lower()
    
    
    @register.filter('replace')
    def dosomething2(value,args):
        return value.replace(args,args.upper())
    
    @register.filter('ADD')
    def dosomething3(value,args1):
        return int(value)+int(args1)
    
    @register.filter('getStudent')
    def getStudents(value):
        id = int(value)
        stu = Students.objects.filter(id = id).first()
        if stu:
            return stu.name
        else:
            return False
    
    
    import datetime
    class CurrentTimeNode(template.Node):
        def __init__(self,formit_string):
            self.formit_string = str(formit_string)
    
        def render(self, context):
            now = datetime.datetime.now()
            return now.strftime(self.formit_string)
    def do_current_time(parser,token):
        try:
            targename,arg = token.contents.split(None,1)
        except ValueError as e:
            raise template.TemplateSyntaxError(str(e))
        else:
            return CurrentTimeNode(arg)

注意事项：

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3NpbmF0XzM4MDY4ODA3_size_16_color_FFFFFF_t_70][]

## （2） 注册app，增加OPTIONS项 ##

## ![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3NpbmF0XzM4MDY4ODA3_size_16_color_FFFFFF_t_70 1][] ##

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3NpbmF0XzM4MDY4ODA3_size_16_color_FFFFFF_t_70 2][]

## （3）前端代码 ##

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3NpbmF0XzM4MDY4ODA3_size_16_color_FFFFFF_t_70 3][]

# （4）视图文件 #

定义在前端显示的变量

def Templatetag(request):
        example = 'hello world'
        num = 5
        return render(request,'templateTag.html',locals())

效果显示：

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80NDIzOTU0MQ_size_16_color_FFFFFF_t_70][]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80NDIzOTQ1NA_size_16_color_FFFFFF_t_70]: /images/20220222/a6db4b8cd9a447a993f31fe178bfa495.png
[20190409163316365.png]: /images/20220222/f7ce7d0648d04f8ca1a53718299bf89e.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3NpbmF0XzM4MDY4ODA3_size_16_color_FFFFFF_t_70]: /images/20220222/387c048c330a4a349222d89f6e96b4cf.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3NpbmF0XzM4MDY4ODA3_size_16_color_FFFFFF_t_70 1]: /images/20220222/6a005aaf50d748a9a4f7422dd40cdcbb.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3NpbmF0XzM4MDY4ODA3_size_16_color_FFFFFF_t_70 2]: /images/20220222/341c661ad16d471bbf96aedd97b2657c.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3NpbmF0XzM4MDY4ODA3_size_16_color_FFFFFF_t_70 3]: /images/20220222/5a670d4dfe3742e09e29c82387ba9800.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80NDIzOTU0MQ_size_16_color_FFFFFF_t_70]: /images/20220222/c849c45435864836a2a450d511d33223.png