form表单及ajax上传示例以及中间件的转换

一.form表单上传文件

渲染:

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <link rel="stylesheet" href="/static/bootstrap-3.3.7-dist/css/bootstrap.css">
     <script src="/static/jquery-3.3.1.js"></script>
</head>
<body>
<h1>form_up</h1>
<form action="" method="post" enctype="multipart/form-data">
    <input type="text" name="username">
    <input type="file" name="my_file">
    <input type="submit">
</form>

</body>
</html>

后台:

def form_up(request):
    if request.method == 'POST':
        print(request.POST)
        import copy
        params = copy.deepcopy(request.POST)
        params["firstname"] = "zhao"
        print(params)
        request.POST = params
        #可利用深拷贝在POST中手动添加键值对
        print(request.POST)
        name = request.POST.get('firstname')
        print(name)
        print(type(name))
        print(request.FILES)
        file_obj = request.FILES.get('my_file')
        print(file_obj.name)
        with open(file_obj.name,'wb') as f:
            for line in file_obj.chunks():
                f.write(line)
        return HttpResponse('OK')
    return render(request,'form_up.html')

二.ajax上传json数据

渲染:

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <link rel="stylesheet" href="/static/bootstrap-3.3.7-dist/css/bootstrap.css">
     <script src="/static/jquery-3.3.1.js"></script>
</head>
<body>
    <button  id="d1">click me!</button>
</body>
<script>
            $('#d1').click(function () {
                   $.ajax({
                       url:'',  // url参数可以不写，默认就是当前页面打开的地址
                       type:'post',
                       contentType:'application/json',
                       data:JSON.stringify({'name':'jason','hobby':'study'}),
                       success:function (data) {
                            alert(data)
                       }
                   })
                })
</script>
</html>

后台:

import json
from django.http import JsonResponse
def ajax_json(request):
    if request.method == 'POST':
        print(request.body)  # json格式只有通过request.body才能查看
        res = json.loads(request.body.decode('utf-8'))
        hobby = res.get('hobby')

        return HttpResponse('OK')  # 必须返回HttpResponse对象
    return render(request, 'ajax_json.html')

三.通过ajax上传文件

渲染:

<link rel="stylesheet" href="/static/bootstrap-3.3.7-dist/css/bootstrap.css">
<script src="/static/jquery-3.3.1.js"></script>



<input type="file" name="myfile" id="i1">
<button id="d1">提交~</button>


<script>
        $('#d1').click(function () {
                   var formdata = new FormData();
                   // FormData对象不仅仅可以传文件还可以传普通的键值对
                    formdata.append('name','jason');
                    // 获取input框存放的文件
                    //$('#i1')[0]由Jquery对象变为js对象
                    formdata.append('myfile',$('#i1')[0].files[0]);
                    $.ajax({
                        url:'',
                        type:'post',
                        data:formdata,
                        // ajax发送文件需要修改两个固定的参数
                        processData:false,  // 告诉浏览器不要处理我的数据
                        contentType:false,  // 不要用任何的编码，就用我formdata自带的编码格式，django能够自动识别改formdata对象
                        // 回调函数
                        success:function (data) {
                            alert(data)
                        }
                    })
                })
</script>

后台:

def ajax_up(request):
        if request.method == 'POST':
            print(request.POST)  # 普通的键值对:<QueryDict: {'name': ['jason']}>
            print(request.FILES)
            # 传文件< MultiValueDict: {'myfile': [ < InMemoryUploadedFile: day17课件.md(application / octet - stream) >]} >
            file_obj = request.FILES.get('myfile')
            with open(file_obj.name, 'wb') as f:
                for line in file_obj.chunks():
                    f.write(line)
            return HttpResponse('OK')
        return render(request, 'ajax_up.html')

四.中间件将jason格式数据转换到request.POST字典中

中间件:

from django.utils.deprecation import MiddlewareMixin
import json


class MyMiddleWare(MiddlewareMixin):
    def process_request(self,request):
        print('我是第一个自定义的中间件中process_request方法')
        import copy
        params = copy.deepcopy(request.POST)
        # params["firstname"] = "zhao"
        # print(params)
        # request.POST = params
        if not request.POST:
            if request.body:
                # < QueryDict: {'username': ['dasdas']} >
                res = json.loads(request.body.decode('utf-8'))
                print(res,type(res))
                for k,v in res.items():
                    params[k] = v
                request.POST = params
                # print(request.POST)


    def process_response(self,request,response):
        print('我是第一个自定义的中间件中process_response方法')
        return response

后台(form表单和ajax_jason数据都能正常通过request.POST取出):

def ajax_json(request):
    if request.method == 'POST':
        # print(request.body)  # json格式只有通过request.body才能查看
        # res = json.loads(request.body.decode('utf-8'))
        # hobby = res.get('hobby')
        print(request.POST.get('hobby'))
        print(request.POST.get('name'))
        return HttpResponse('OK')  # 必须返回HttpResponse对象
    return render(request, 'ajax_json.html')

原文地址：https://www.cnblogs.com/sima-3/p/11390011.html