django进阶
Posted MKY-技术驿站
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，多对多：
创建多对多：
方式一：自定义关系表
class Host(models.Model): nid=models.AutoField(primary_key=True) hostname=models.CharField(max_length=32,db_index=True) ip=models.GenericIPAddressField(db_index=True) port=models.IntegerField() b=models.ForeignKey(\'Business\',to_field=\'id\') #自定义关联 class HostToApp(models.Model): hobj=models.ForeignKey(to=\'Host\',to_fields=\'nid\') aobj=models.ForeignKey(to=\'Application\',to_fields=\'id\')
对表的操作和foreignkey一样，并且可以直接对这个表进行操作
HostToApp.objects.create(hobj_id=1,aobj_id=2)
方式二：自动创建关系表
1 class Host(models.Model): 2 nid=models.AutoField(primary_key=True) 3 hostname=models.CharField(max_length=32,db_index=True) 4 ip=models.GenericIPAddressField(db_index=True) 5 port=models.IntegerField() 6 b=models.ForeignKey(\'Business\',to_field=\'id\') 7 8 class Application(models.Model): 9 name=models.CharField(max_length=64) 10 auto=models.ManyToManyField("Host")
缺点就是无法直接对第三张表进行操作，只能间接的方式来操作并且也无法在这个表增加多余字段
#现获取对象
obj = Application.objects.get(id=1)
# 然后间接操作第三张表中的内容
#增加
obj.r.add(1)#Application=1 host=1 obj中已经存在了app id 所以这里的add=1就是host表中的id
obj.r.add(2)#Application=1 host=2
obj.r.add(2,3,4)#Application=1 host=2/3/4
obj.r.add(*[1,2,3,4])
#移除
obj.r.remove(1)
obj.r.remove(2,4)
obj.r.remove(*[1,2,3])
#清空obj中的app id =1的所有内容
obj.r.clear()
#更新
obj.r.set([3,5,7])
# 所有相关的主机对象“列表” QuerySet
obj.r.all()
增删改查例子
def app(reques): obj=models.Application.objects.all() print(obj) for i in obj: #查询 print(i.name,i.auto.all()) #增加app项目并且返回这个obj对象 #obj=models.Application.objects.create(name=\'oracle\') #增加1,3,4host到app #obj.auto.add(*[1,4,3]) #删除 # obj=models.Application.objects.get(id=1) # obj.auto.remove(1) # return render(reques,\'app.html\',{\'obj\':obj}) return HttpResponse("ok")
获取用户请求头
def test(request): #查看源码 #<class \'django.core.handlers.wsgi.WSGIRequest\'> from django.core.handlers.wsgi import WSGIRequest print(type(request)) #查询 for x,v in request.environ.items(): print(x,v) return HttpResponse("Ok")
结果(用到最多的就是HTTP_USER_AGENT，判断客户端用的什么设备类型)：
1 (\'TMP\', \'C:\\\\Users\\\\ADMIN~1.MEN\\\\AppData\\\\Local\\\\Temp\') 2 (\'PYTHONIOENCODING\', \'UTF-8\') 3 (\'COMPUTERNAME\', \'MENKEYI\') 4 (\'wsgi.multiprocess\', False) 5 (\'PROCESSOR_LEVEL\', \'6\') 6 (\'RUN_MAIN\', \'true\') 7 (\'HTTP_COOKIE\', \'csrftoken=mjMaE6agb2Si4NrdFacQpUIkviQIFv3C; _ga=GA1.1.627222119.1494076915; Hm_lvt_a033dafefef77193d4d80cc7103c9772=1493689044,1494076914,1494228704,1\'494597132\') 8 (\'USERDOMAIN\', xxxxxxxx\') 9 (\'GOROOT\', \'C:\\\\Go\\\\app\') 10 (\'SERVER_PROTOCOL\', \'HTTP/1.1\') 11 (\'SERVER_SOFTWARE\', \'WSGIServer/0.1 Python/2.7.9\') 12 (\'PSMODULEPATH\', \'C:\\\\Windows\\\\system32\\\\WindowsPowerShell\\\\v1.0\\\\Modules\\\\\') 13 (\'SCRIPT_NAME\', u\'\') 14 (\'COMMONPROGRAMFILES\', \'C:\\\\Program Files\\\\Common Files\') 15 (\'PROCESSOR_IDENTIFIER\', \'Intel64 Family 6 Model 70 Stepping 1, GenuineIntel\') 16 (\'REQUEST_METHOD\', \'GET\') 17 (\'wsgi.version\', (1, 0)) 18 (\'PROGRAMFILES\', \'C:\\\\Program Files\') 19 (\'PROCESSOR_REVISION\', \'4601\') 20 (\'SYSTEMROOT\', \'C:\\\\Windows\') 21 (\'QUERY_STRING\', \'\') 22 (\'PATH\', \'C:\\\\ProgramData\\\\Oracle\\\\Java\\\\javapath;C:\\\\Program Files (x86)\\\\Common Files\\\\NetSarang;C:\\\\Program Files (x86)\\\\Intel\\\\iCLS Client\\\\;C:\\\\Program Files\\\\Intel\\\\iCLS Client\\\\;C:\\\\Windows\\\\system32;C:\\\\Windows;C:\\\\Windows\\\\System32\\\\Wbem;C:\\\\Windows\\\\System32\\\\WindowsPowerShell\\\\v1.0\\\\;C:\\\\Program Files\\\\Intel\\\\Intel(R) Management Engine Components\\\\DAL;C:\\\\Program Files\\\\Intel\\\\Intel(R) Management Engine Components\\\\IPT;C:\\\\Program Files (x86)\\\\Intel\\\\Intel(R) Management Engine Components\\\\DAL;C:\\\\Program Files (x86)\\\\Intel\\\\Intel(R) Management Engine Components\\\\IPT;C:\\\\Program Files\\\\Intel\\\\WiFi\\\\bin\\\\;C:\\\\Program Files\\\\Common Files\\\\Intel\\\\WirelessCommon\\\\;C:\\\\Program Files\\\\Hewlett-Packard\\\\SimplePass\\\\;C:\\\\Program Files\\\\Microsoft SQL Server\\\\110\\\\Tools\\\\Binn\\\\;C:\\\\Python27;C:\\\\Python27\\\\Scripts;C:\\\\Program Files (x86)\\\\mysql\\\\MySQL Server 5.5\\\\bin;C:\\\\Python27\\\\Lib\\\\site-packages\\\\Django-1.7.7-py2.7.egg\\\\django\\\\bin;C:\\\\Program Files (x86)\\\\IDM Computer Solutions\\\\UltraEdit;C:\\\\Program Files\\\\Windows Imaging\\\\;C:\\\\Program Files (x86)\\\\OpenVPN\\\\bin;C:\\\\Program Files\\\\Git\\\\cmd;C:\\\\Go\\\\bin;d:\\\\Program Files (x86)\\\\erl5.10.4\\\\bin;D:\\\\Program Files (x86)\\\\RabbitMQ Server\\\\rabbitmq_server-3.2.4\\\\sbin\') 23 (\'PYTHONUNBUFFERED\', \'1\') 24 (\'PROGRAMFILES(X86)\', \'C:\\\\Program Files (x86)\') 25 (\'#ENVKKPRBC_CMDILNE\', \'\') 26 (\'CONTENT_LENGTH\', \'\') 27 (\'HTTP_UPGRADE_INSECURE_REQUESTS\', \'1\') 28 (\'HTTP_CACHE_CONTROL\', \'max-age=0\') 29 (\'HTTP_CONNECTION\', \'keep-alive\') 30 (\'REMOTE_HOST\', \'\') 31 (\'TEMP\', \'C:\\\\Users\\\\ADMIN~1.MEN\\\\AppData\\\\Local\\\\Temp\') 32 (\'REMOTE_ADDR\', \'127.0.0.1\') 33 (\'COMMONPROGRAMFILES(X86)\', \'C:\\\\Program Files (x86)\\\\Common Files\') 34 (\'#ENVTSLOGRBCSHELLEXT3340\', \'64101024\') 35 (\'PROCESSOR_ARCHITECTURE\', \'AMD64\') 36 (\'wsgi.url_scheme\', \'http\') 37 (\'ALLUSERSPROFILE\', \'C:\\\\ProgramData\') 38 (\'SHELLLAUNCH{A81BA54B-CCFE-4204-8E79-A68C0FDFA5CF}\', \'ShellExt\') 39 (\'LOCALAPPDATA\', \'C:\\\\Users\\\\admin.menkeyi\\\\AppData\\\\Local\') 40 (\'HOMEPATH\', \'\\\\Users\\\\admin.menkeyi\') 41 (\'USERDOMAIN_ROAMINGPROFILE\', \'xxxxxx\') 42 (\'VS120COMNTOOLS\', \'D:\\\\Program Files (x86)\\\\Microsoft Visual Studio 12.0\\\\Common7\\\\Tools\\\\\') 43 (\'ERLANG_HOME\', \'d:\\\\Program Files (x86)\\\\erl5.10.4\') 44 (\'USERNAME\', \'admin\') 45 (\'HTTP_ACCEPT\', \'text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8\') 46 (\'#ENVTSLOGSSS3340\', \'64102944\') 47 (\'LOGONSERVER\', \'\\\\\\\\MENKEYI\') 48 (\'COMSPEC\', \'C:\\\\Windows\\\\system32\\\\cmd.exe\') 49 (\'PROGRAMDATA\', \'C:\\\\ProgramData\') 50 (\'wsgi.file_wrapper\', <class wsgiref.util.FileWrapper at 0x0000000003A08E88>) 51 (\'PYTHONPATH\', \'E:\\\\mydjango\') 52 (\'RABBITMQ_SERVER\', \'D:\\\\Program Files (x86)\\\\RabbitMQ Server\') 53 (\'wsgi.multithread\', True) 54 (\'wsgi.input\', <socket._fileobject object at 0x0000000003C0AA20>) 55 (\'HTTP_USER_AGENT\', \'Mozilla/5.0 (Windows NT 6.3; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/58.0.3029.81 Safari/537.36\') 56 (\'HTTP_HOST\', \'127.0.0.1:8000\') 57 (\'SESSIONNAME\', \'Console\') 58 (\'PATHEXT\', \'.COM;.EXE;.BAT;.CMD;.VBS;.VBE;.JS;.JSE;.WSF;.WSH;.MSC\') 59 (\'PATH_INFO\', u\'/app01/test/\') 60 (\'FP_NO_HOST_CHECK\', \'NO\') 61 (\'WINDIR\', \'C:\\\\Windows\') 62 (\'#ENVTSLOGTSLOG3340\', \'64101664\') 63 (\'HTTP_ACCEPT_ENCODING\', \'gzip, deflate, sdch, br\') 64 (\'SERVER_PORT\', \'8000\') 65 (\'MOZ_PLUGIN_PATH\', \'C:\\\\Program Files (x86)\\\\Foxit Software\\\\Foxit Reader\\\\plugins\\\\\') 66 (\'HOMEDRIVE\', \'C:\') 67 (\'SERVER_NAME\', \'axxxxxi\') 68 (\'wsgi.run_once\', False) 69 (\'#ENVTSLOGXMEDIALIBRARY3340\', \'280591264\') 70 (\'SYSTEMDRIVE\', \'C:\') 71 (\'GATEWAY_INTERFACE\', \'CGI/1.1\') 72 (\'HTTP_ACCEPT_LANGUAGE\', \'zh-CN,zh;q=0.8\') 73 (\'PYCHARM_HOSTED\', \'1\') 74 (\'NUMBER_OF_PROCESSORS\', \'8\') 75 (\'APPDATA\', \'C:\\\\Users\\\\admin.menkeyi\\\\AppData\\\\Roaming\') 76 (\'DJANGO_SETTINGS_MODULE\', \'mydjango.settings\') 77 (\'PROGRAMW6432\', \'C:\\\\Program Files\') 78 (\'CONTENT_TYPE\', \'text/plain\') 79 (\'wsgi.errors\', <open file \'<stderr>\', mode \'w\' at 0x00000000020FB150>) 80 (\'COMMONPROGRAMW6432\', \'C:\\\\Program Files\\\\Common Files\') 81 (\'OS\', \'Windows_NT\') 82 (\'PUBLIC\', \'C:\\\\Users\\\\Public\') 83 (\'USERPROFILE\', \'C:\\\\Users\\\\admin\')
分页(手动写)
view
1 def user_list(request): 2 #模拟数据库数据 3 users=range(200) 4 5 #从前端接受过来的都是字符串,request.GET.get(\'p\',1)如果p为空那么值为1 6 #获取当前页 7 curr_pager_num=int(request.GET.get(\'p\',1)) 8 9 #每个页面显示几条数据 10 page_data_num=10 11 12 13 14 #开始索引 15 start=(curr_pager_num-1)*page_data_num 16 #结束索引 17 end=curr_pager_num*page_data_num 18 #根据star和end做页面数据切分 19 data=users[start:end] 20 21 #获取数据总页数 22 all_count=len(users) 23 24 #计算分页数量 25 total_count,y=divmod(all_count,page_data_num) 26 #y>1分页就总数就加1 27 if y: 28 total_count += 1 29 30 #存储分页内容列表 31 page_str_list=[] 32 33 #页面页码尽量是基数不能小于5 34 pager_num=11 35 36 #总页数小于11 37 if total_count < pager_num : 38 start_index=1 39 end_index=total_count+1 40 41 else: 42 #当前页小于6 43 if curr_pager_num <6: 44 start_index=1 45 #end_index=11 + 1 46 end_index=pager_num + 1 47 else: 48 #总页数大于11:start_index= curr_pager_num -5 49 start_index= curr_pager_num - (pager_num - 1)/2 50 #end_index=curr_pager_num + 6 51 end_index=curr_pager_num + (pager_num + 1)/2 52 #curr_pager_num+ 5) 53 if (curr_pager_num+ (pager_num - 1)/2) > total_count: 54 #start_index=total_count - 11 + 1 55 start_index=total_count - pager_num + 1 56 end_index=total_count+1 57 58 59 if curr_pager_num ==1: 60 prev=\'<a class="page" href="javascript:void(0)">上一页</a>\' 61 else: 62 #上一页 63 prev=\'<a class="page" href="/user_list/?p=%s">上一页</a>\'%(curr_pager_num - 1) 64 page_str_list.append(prev) 65 #循环增加 66 for i in range(int(start_index),int(end_index)): 67 68 #当前页面class中增加active属性 69 if i == curr_pager_num: 70 temp=\'<a class="page active" href="/user_list/?p=%s">%s</a>\'%(i,i) 71 else: 72 temp=\'<a class="page" href="/user_list/?p=%s">%s</a>\'%(i,i) 73 74 #追加到列表 75 page_str_list.append(temp) 76 77 78 #当前页等于最大页数就不在加1 79 if curr_pager_num == total_count: 80 next_page=\'<a class="page" href="javascript:void(0)">下一页</a>\' 81 else: 82 next_page=\'<a class="page" href="/user_list/?p=%s">下一页</a>\'%(curr_pager_num + 1) 83 page_str_list.append(next_page) 84 85 86 #跳转页 87 jump=""" 88 <input type=\'text\'/><a onclick=\'jumpTo(this,"/user_list/?p=")\' id=\'jump_id\'>GO</a> 89 <script> 90 function jumpTo(ths,base){ 91 var val = ths.previousSibling.value; 92 location.href = base + val; 93 } 94 </script> 95 """ 96 page_str_list.append(jump) 97 98 #将列表进行字符串拼接返回前端 99 page_str="".join(page_str_list) 100 101 102 103 #page_str=mark_safe("",join(page_list))前端将信任这代码 104 105 return render(request,\'user_list.html\',{\'li\':data,\'page_str\':page_str})
url
url(r\'^user_list/$\', views.user_list),
html，中的incloud 的html和上一个例子中的一样
1 <!DOCTYPE html> 2 <html lang="en"> 3 <head> 4 <meta charset="UTF-8"> 5 <title>Title</title> 6 <style> 7 .pagediv .page{ 8 display: inline-block; 9 padding: 5px; 10 background-color: aqua; 11 margin: 5px; 12 } 13 .pagediv .page.active{ 14 background-color: darkgreen; } 15 </style> 16 </head> 17 <body> 18 19 <ul > 20 {% include \'li.html\' %} 21 </ul> 22 <div class="pagediv"> 23 {{ page_str|safe }} 24 </div> 25 </body> 26 </html>
1 {% for user in li %} 2 <li> {{ user }}</li> 3 {% endfor %}
将上面的代码改造成类方式实现
view
1 from utlis import pagination 2 3 def user_list(request): 4 #模拟数据库数据 5 users=range(200) 6 7 #获取当前页 8 current_page = request.GET.get(\'p以上是关于django进阶的主要内容，如果未能解决你的问题，请参考以下文章我的C语言学习进阶之旅解决 Visual Studio 2019 报错：错误 C4996 ‘fscanf‘: This function or variable may be unsafe.(代码片段
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