<?php ?> ……<?php ?>中的 是啥作用？谢谢
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在php中，大括号“”可以起到如下作用：1.将多个独立语句合并为一个复合语句，例如 if ... else ...中经常如此使用
2.在变量间接引用中进行定界，避免歧义。例如 $$my_var[8]与$$my_var[8]的区分
你的<?php ?> ……<?php ?>应该属于第一种情况，是符合语句的定界符。 参考技术A php中花括号“”的作用:
在PHP中，大括号“”的作用如下：
将多个独立语句合并为一个复合语句.
例如 if ... else ...中经常如此使用
在变量间接引用中进行定界，避免歧义。例如 $$my_var[8]与$$my_var[8]的区分
用于指示字符串变量中的单个字符（下标从0开始），例如
$my_str="1234";
$my_str1='5'; //现在 $my_str 内容为 '1534'此用法为PHP 5之后的特性，用于消除使用中括号引起的歧义 参考技术B 就是一个说明运算顺序和解释函数整体的作用
渲染错误：没有找到没有参数的“ph”反向。尝试了 1 种模式：['(?P<answer>[^/]+)/ph\\-data/$']
【中文标题】渲染错误：没有找到没有参数的“ph”反向。尝试了 1 种模式：[\'(?P<answer>[^/]+)/ph\\\\-data/$\']【英文标题】：Rendering error: Reverse for 'ph' with no arguments not found. 1 pattern(s) tried: ['(?P<answer>[^/]+)/ph\\-data/$']渲染错误：没有找到没有参数的“ph”反向。尝试了 1 种模式：['(?P<answer>[^/]+)/ph\\-data/$'] 【发布时间】：2019-05-23 08:30:21 【问题描述】：我是编码新手，在这里我正在尝试构建一个网站，该网站只接受用户希望从选定范围内看到的内容，因为我运行服务器时遇到了这个错误：
Environment:
Request Method: GET
Request URL: http://127.0.0.1:8000/
Django Version: 2.1.3
Python Version: 3.7.1
Installed Applications:
['django.contrib.admin',
'django.contrib.auth',
'django.contrib.contenttypes',
'django.contrib.sessions',
'django.contrib.messages',
'django.contrib.staticfiles',
'rest_framework',
'zigview']
Installed Middleware:
['django.middleware.security.SecurityMiddleware',
'django.contrib.sessions.middleware.SessionMiddleware',
'django.middleware.common.CommonMiddleware',
'django.middleware.csrf.CsrfViewMiddleware',
'django.contrib.auth.middleware.AuthenticationMiddleware',
'django.contrib.messages.middleware.MessageMiddleware',
'django.middleware.clickjacking.XFrameOptionsMiddleware']
Template error:
In template C:\Users\user\Desktop\Frouniter\FrounterWeb- postgreDB\zigview\templates\FrounterWeb\index.html, error at line 12
Reverse for 'ph' with no arguments not found. 1 pattern(s) tried: ['(?P<answer>[^/]+)/ph\\-data/$']
2 : <html lang="en">
3 : <head>
4 : %load staticfiles%
5 : <!-- Mobile resizing and bootstrap -->
6 : %include 'FrounterWeb/Lib-includes/Mobile-Response.html'%
7 :
8 : <!-- Javascript action-->
9 : %include 'FrounterWeb/Lib-includes/JavaScript-action.html'%
10 :
11 : <!-- Libary of chart and gage -->
12 : %include 'FrounterWeb/Lib-includes/Gr aphs-files.ht ml'%
13 :
14 : <link rel="shortcut icon" type="image/png" href="% static 'FrounterWeb/img/Logo.png' %">
15 : <title>Frounter-Agrotech monitoring</title>
16 :
17 :
18 :
19 :
20 : </head>
21 :
22 : <body class="body" style="background-color:#f6f6f6">
Traceback:
File "C:\Users\user\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\core\handlers\exception.py" in inner
34. response = get_response(request)
File "C:\Users\user\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\core\handlers\base.py" in _get_response
156. response = self.process_exception_by_middleware(e, request)
File "C:\Users\user\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\core\handlers\base.py" in _get_response
154. response = response.render()
File "C:\Users\user\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\template\response.py" in render
106. self.content = self.rendered_content
File "C:\Users\user\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\template\response.py" in rendered_content
83. content = template.render(context, self._request)
File "C:\Users\user\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\template\backends\django.py" in render
61. return self.template.render(context)
File "C:\Users\user\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\template\base.py" in render
171. return self._render(context)
File "C:\Users\user\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\template\base.py" in _render
163. return self.nodelist.render(context)
File "C:\Users\user\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\template\base.py" in render
937. bit = node.render_annotated(context)
File "C:\Users\user\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\template\base.py" in render_annotated
904. return self.render(context)
File "C:\Users\user\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\template\loader_tags.py" in render
150. return compiled_parent._render(context)
File "C:\Users\user\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\template\base.py" in _render
163. return self.nodelist.render(context)
File "C:\Users\user\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\template\base.py" in render
937. bit = node.render_annotated(context)
File "C:\Users\user\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\template\base.py" in render_annotated
904. return self.render(context)
File "C:\Users\user\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\template\defaulttags.py" in render
309. return nodelist.render(context)
File "C:\Users\user\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\template\base.py" in render
937. bit = node.render_annotated(context)
File "C:\Users\user\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\template\base.py" in render_annotated
904. return self.render(context)
File "C:\Users\user\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\template\loader_tags.py" in render
62. result = block.nodelist.render(context)
File "C:\Users\user\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\template\base.py" in render
937. bit = node.render_annotated(context)
File "C:\Users\user\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\template\base.py" in render_annotated
904. return self.render(context)
File "C:\Users\user\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\template\defaulttags.py" in render
442. url = reverse(view_name, args=args, kwargs=kwargs, current_app=current_app)
File "C:\Users\user\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\urls\base.py" in reverse
90. return iri_to_uri(resolver._reverse_with_prefix(view, prefix, *args, **kwargs))
File "C:\Users\user\AppData\Local\Programs\Python\Python37-32\lib\site-packages\django\urls\resolvers.py" in _reverse_with_prefix
622. raise NoReverseMatch(msg)
Exception Type: NoReverseMatch at /
Exception Value: Reverse for 'ph' with no arguments not found. 1 pattern(s) tried: ['(?P<answer>[^/]+)/ph\\-data/$']
对不起，我问了这么简单的问题
我尝试过的：
尝试切换到 pk: 到
尝试添加到 slug 或
我看了这个网址链接：Django - getting Error "Reverse for 'detail' with no arguments not found. 1 pattern(s) tried:" when using % url "music:fav" %
我的代码：
我的观点代码：
try:
class index(ListView):
model = tank_system
template_name = 'FrounterWeb/extends/includes.html'
ordering = ['-datetime']
def get_context_data(self,**kwargs):
return'tank':self.get_queryset()
#def get_queryset(self):
# return
except:
logger.error('index page request failed/errors')
try:
class ph(ListView):
model = tank_system
template_name = 'FrounterWeb/extends/ph.html'
context_object_name = tank_system
ordering = ['-datetime'] # sort dates in descending order
def post(self, request, answer):
if request.method == 'POST':
form = YourForm(request.POST)
if form.is_valid():
answer = form.cleaned_data['value']
def get_context_data(self, **kwargs):
#do a selection of which path to do
return'tank': self.get_queryset()
except:
logger.error('PH page Functions failed/errors')
应用 URl 代码：
from django.urls import path
from . import views #function views
path(r'<str:answer>/ph-data/', login_required(views.ph.as_view()), name='ph'),
我的 HTML 代码供用户输入数据：
%block Buttonbar%
<div class="container-fluid">
<div class="mx-auto">
<nav class="navbar navbar-dark bg-primary">
<div class = "container-fluid" >
<form action="% url 'zigview:ph-data' answer %" method = "post">
<select class="custom-select" id="datetimefilter" name = "dropdown">
<option selected="selected" disabled>Select:</option>
<option value="Today">Today</option>
<option value="Yestday">Yestday</option>
<option value="ThWeek">This Week</option>
<option value="PreWeek">Previous Week</option>
<option value="ThMonths">This Months</option>
<option value="PerMonths">Previous Month</option>
<option value="Thisyear">This Year</option>
<option value="Lastyear">Last Year</option>
</select>
% csrf_token %
<input type="submit" value="post" name="submit-select">
<div class="container-fluid">
<a>Select Range Dates:<input class="form-control" type="date"/> to <input class="form-control" type="date"/></a>
</div>
</form>
</div>
</nav>
</div>
</div>
%endblock Buttonbar%
总结什么结果：
我希望能够接收变量，也许现在可以从控制台看到，这个变量将被传递到 python 脚本并使用它来选择数据、月份和年份来查看
【问题讨论】：
【参考方案1】：您的问题似乎是当您的模板呈现时 answer 未定义（我没有看到它添加到任何上下文中）。在answer 中获得值后，您应该能够执行以下操作：
% url 'zigview:ph-data' answer=answer %
更新：OP 不知道如何将answer 添加到他的上下文字典中，所以我将在这部分进行扩展。要将其他值添加到上下文字典中，请将它们添加到基于类的视图的 get_context_data 方法中：
class ph(TemplateView):
...
def get_context_data(self, **kwargs):
# do a selection of which path to do
return
'tank': self.get_queryset(),
'answer': 42,
# the answer that we use above will be used as the parameter to the url in the template.
【讨论】：
您是否将answer 添加到ph.get_context_data 的上下文字典中？
我不这么认为，我该如何添加，对不起:(以上是关于<?php ?> ……<?php ?>中的 是啥作用？谢谢的主要内容，如果未能解决你的问题，请参考以下文章