Python-Django-Ajax进阶

ajax上传文件:

<h2>基于ajax上传文件</h2>
<p>名字 <input type="text" id="filename"></p>
<p>文件 <input type="file" id="file"></p>
<button id="filebtn">上传文件</button>

$('#filebtn').click(function () {
    //js取到文件
    var myfile=$('#file')[0].files[0]
    //生成一个FormData对象
    var formdata=new FormData
    //放值  //放文件
    formdata.append('name',$('#filename').val())
    formdata.append('myfile',myfile)
    $.ajax({
        url:'/fileupload/',
        type:'post',
         //这两个要必须写
        processData:false, //不预处理数据  因为FormData 已经做了
        contentType:false, //我不指定编码了 因为FormData 已经做了
        data:formdata,
        success:function (data) {
            console.log(data)
            alert(data)
        }
    })
})

# ajax文件上传
def fileupload(request):
    if request.method == 'GET':
        return render(request, 'fileupload.html')
    if request.is_ajax():
        name = request.POST.get('name')
        # 文件对象
        myfile = request.FILES.get('myfile')
        import os
        path = os.path.join('media', name)
        with open(path, 'wb') as f:
            for line in myfile:
                f.write(line)
        return HttpResponse('success')

django自带序列化:

# ajax page,了解,django自带的序列化
def page(request):
    if request.method == 'GET':
        users = UserInfo.objects.all()
        # json序列
        # user_dic = [{'name': user.name, 'age': user.age, 'id': user.id} for user in users]
        # return JsonResponse(user_dic, safe=False, json_dumps_params={'ensure_ascii': False})
        # 显示结果[{"name": "abc1", "age": 11, "id": 1}, {"name": "ewe", "age": 12, "id": 2}]
        # 了解,django自带的序列化
        user_dic = serializers.serialize('json', users)
        return HttpResponse(user_dic)
        # 显示结果[{"model": "app01.userinfo", "pk": 1, "fields": {"name": "abc1", "age": 11}}, {"model": "app01.userinfo", "pk": 2, "fields": {"name": "ewe", "age": 12}}]

批量插入数据bulk_create

# 批量插入数据bulk_create
def pagemass(request):
    #     # objes:对象列表,batch_size 一次插入数据的量
    li = []
    for i in range(200):
        # UserInfo.objects.create() #老大方式
        li.append(UserInfo(name='abc%s' % i, age=i + 1))
    ret = UserInfo.objects.bulk_create(li, 20)
    return HttpResponse('ok')

分页器组件:

# 分页器
from django.core.paginator import Paginator
def paging(request):
    users = UserInfo.objects.all().order_by('pk')
    paginator = Paginator(users, 20)
    try:
        currentpage = int(request.GET.get('page', 1))  # 默认显示第一页
        page = paginator.page(currentpage)
    except Exception as e:
        # 出错时显示第一页
        currentpage = 1
        page = paginator.page(currentpage)
    # 传入页码数,拿到的就是当前页对象
    page = paginator.page(currentpage)
    # 1 总页数是否大于11,当总页码数大于11
    if paginator.num_pages > 11:
        # 1.1 当前页码数是否小于6
        if currentpage <= 6:
            # 1.1.1 当当前页码小于6的时候,就生成11个页码数
            page_range = range(1, 12)
        # 1.2 当当前页码+5 大于等于总页码数
        elif currentpage + 5 >= paginator.num_pages:
            # 1.2.1 往后推11个页码数
            page_range = range(paginator.num_pages - 10, paginator.num_pages + 1)
        # 1.3 生成一个左5 右5的区间
        else:
            page_range = range(currentpage - 5, currentpage + 6)
    # 2 总页码数不大于11 ,有多少,显示多少
    else:
        page_range = paginator.page_range
    return render(request, 'page.html', locals())

<table class="table">
                <thead>
                <tr>
                    <th>id</th>
                    <th>name</th>
                    <th>age</th>
                </tr>
                </thead>
                <br>
                <tbody>
{#                循环的时page不是users#}
                {% for user in page %}
                    <tr>
                        <td>{{ forloop.counter }}</td>
                        <td>{{ user.name }}</td>
                        <td>{{ user.age }}</td>
                    </tr>
                {% endfor %}
                </tbody>
            </table>
            <nav aria-label="Page navigation">
                <ul class="pagination">
                    {#                    上一页判断#}
                    {% if page.has_previous %}
                        <li>
                            <a href="/paging/?page={{ page.previous_page_number }}" aria-label="Previous">
                                <span aria-hidden="true">上一页</span>
                            </a>
                        </li>
                    {% else %}
                        <li class="disabled">
                            <a href="" aria-label="Previous">
                                <span aria-hidden="true">上一页</span>
                            </a>
                        </li>
                    {% endif %}

                    {# 判断当前页面是否是循环到的页码,如果是,加active#}
                    {% for foo in page_range %}
                        {% if currentpage == foo %}
                            <li class="acitve"><a href="/paging/?page={{ foo }}">{{ foo }}</a></li>
                        {% else %}
                            <li><a href="/paging/?page={{ foo }}">{{ foo }}</a></li>
                        {% endif %}
                    {% endfor %}

                    {#                    下一页判断#}
                    {% if page.has_next %}
                        <li>
                            <a href="/paging/?page={{ page.next_page_number }}" aria-label="Next">
                                <span aria-hidden="true">下一页</span>
                            </a>
                        </li>
                    {% else %}
                        <li class="disabled">
                            <a href="" aria-label="Next">
                                <span aria-hidden="true">下一页</span>
                            </a>
                        </li>
                    {% endif %}


                </ul>
            </nav>

　　

forms组件:(数据校验功能)

<form action="">
                <p>name <input type="text" name="name"></p>
                <p>pwd <input type="password" name="pwd"></p>
                <p>email <input type="email" name="email"></p>
                <input type="submit">
            </form>
            <h1>forms的模板渲染之一(推荐)</h1>
            <form action="" method="post" novalidate>
                <p>name: {{ myform.name }}</p>
                <p>pwd: {{ myform.pwd }}</p>
                <p>email: {{ myform.email }}</p>
                <input type="submit">
            </form>
            <h1>forms的模板渲染之二(推荐!!!!!)</h1>
            <form action="" method="post" novalidate>
                {% for item in myform %}
                    <p>{{ item.label }}:{{ item }}</p>
                {% endfor %}
                <input type="submit">
            </form>
            <h1>forms的模板渲染之三</h1>
            <form action="" method="post" novalidate>
                {{ myform.as_p }}
                <input type="submit">
            </form>

from django import forms
# 继承Form这个类
class MyForm(forms.Form):
    # 限制name这个字段最长为8,最短为3
    name=forms.CharField(min_length=3,max_length=8,label='用户名',required=True,error_messages={'min_length':'至少为3','max_length':'最长为8,您太长了'})
    pwd=forms.CharField(min_length=3,max_length=8,label='密码',error_messages={'min_length':'至少为3','max_length':'最长为8,您太长了'})
    email=forms.EmailField(label='邮箱',error_messages={'invalid':'邮箱格式不合法','required':'这个字段必填'})

# ajax register
def register(request):
    if request.method == 'GET':
        myform=MyForm()
        return render(request, 'register.html',locals())
    else:
        # 生成对象,传参,传字典,要校验数据的字典
        # myform=MyForm(request.POST)
        # 自己写要校验的字典,数据多了,多的是不校验的,但是cleaned_data中也没有多出来的数据
        # dic={'name':'lqz','pwd':'123','email':'[email protected]','xx':'xxx'}
        # dic={'name':'lqz','pwd':'123','email':'22'}
        # dic = {'name': 'abc', 'pwd': '122', 'email': '5555'}
        name=request.POST.get('name')
        pwd=request.POST.get('pwd')
        email=request.POST.get('email')
        dic = {'name': name, 'pwd': pwd, 'email': email}
        print(dic)
        myform = MyForm(dic)
        # 所有字典都校验通过,它就是True的
        if myform.is_valid():
            # 取出校验通过的数据
            clean_data=myform.changed_data
            print(clean_data)
            # models.UserInfo.objects.create(**clean_data)
        else:
            # 所有的错误信息
            # 只要是校验通过的值,都在cleaned_data中放着
            print(myform.changed_data)
            print(myform.errors.as_data())
            # 字典类型
            print(type(myform.errors))
            print(myform.errors.get('name'))
            from  django.forms.utils import ErrorDict
    return HttpResponse('OK')

　　

ajax总结:

1 默认编码urlencode,后端按照原来form表单提交的形式取值就可以了()
2 上传文件,form-data编码,后端按照原来form表单提交的形式取值就可以了,取数据从POST中取,取文件从FILES中取
3 上传json格式,django不会处理数据,需要自己处理,自己从body体中取出数据处理