Django学习——视图层HttpResponse、render、redirect本质、JsonResponse

HttpResponse、render、redirect本质

django视图函数必须要返回一个HttpResponse对象

def render(request, template_name, context=None, content_type=None, status=None, using=None):
    """
    Return a HttpResponse whose content is filled with the result of calling
    django.template.loader.render_to_string() with the passed arguments.
    """
    content = loader.render_to_string(template_name, context, request, using=using)
    return HttpResponse(content, content_type, status)


class HttpResponse(HttpResponseBase):
    """
    An HTTP response class with a string as content.

    This content can be read, appended to, or replaced.
    """

    streaming = False

    def __init__(self, content=b'', *args, **kwargs):
        super().__init__(*args, **kwargs)
        # Content is a bytestring. See the `content` property methods.
        self.content = content

    def __repr__(self):
        return '<%(cls)s status_code=%(status_code)d%(content_type)s>' % {
            'cls': self.__class__.__name__,
            'status_code': self.status_code,
            'content_type': self._content_type_for_repr,
        }

    def serialize(self):
        """Full HTTP message, including headers, as a bytestring."""
        return self.serialize_headers() + b'\r\n\r\n' + self.content

    __bytes__ = serialize

    @property
    def content(self):
        return b''.join(self._container)

    @content.setter
    def content(self, value):
        # Consume iterators upon assignment to allow repeated iteration.
        if (
            hasattr(value, '__iter__') and
            not isinstance(value, (bytes, memoryview, str))
        ):
            content = b''.join(self.make_bytes(chunk) for chunk in value)
            if hasattr(value, 'close'):
                try:
                    value.close()
                except Exception:
                    pass
        else:
            content = self.make_bytes(value)
        # Create a list of properly encoded bytestrings to support write().
        self._container = [content]

    def __iter__(self):
        return iter(self._container)

    def write(self, content):
        self._container.append(self.make_bytes(content))

    def tell(self):
        return len(self.content)

    def getvalue(self):
        return self.content

    def writable(self):
        return True

    def writelines(self, lines):
        for line in lines:
            self.write(line)
            
redirect内部是继承了HttpResponse类

JsonResponse

需求：给前端返回json格式数据
方式1：自己序列化
	 # res = json.dumps(d,ensure_ascii=False)
    # return HttpResponse(res)
方式2：JsonResponse
    import json
    from django.http import JsonResponse
    def func2(request):
        d = {'user':'jason好帅','password':123}
        return JsonResponse(d)

ps:额外参数补充

json_dumps_params={'ensure_ascii':False}  # 看源码
safe=False  # 看报错信息

# JsonResponse返回的也是HttpResponse对象