web框架开发-Django的Forms组件

校验字段功能

针对一个实例:用户注册。

image


模型:models.py

class UserInfo(models.Model):
    name=models.CharField(max_length=32)
    pwd=models.CharField(max_length=32)
    email=models.EmailField()
    tel=models.CharField(max_length=32)


模板: reg.html:

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>

</head>
<body>

<form action="" method="post">
    {% csrf_token %# 为了通过中间件检验
    <div>
        <label for="user">用户名</label>
        <p><input type="text" name="name" id="name"></p>
    </div>
    <div>
        <label for="pwd">密码</label>
        <p><input type="password" name="pwd" id="pwd"></p>
    </div>
    <div>
        <label for="r_pwd">确认密码</label>
        <p><input type="password" name="r_pwd" id="r_pwd"></p>
    </div>
     <div>
        <label for="email">邮箱</label>
        <p><input type="text" name="email" id="email"></p>
    </div>
    <input type="submit">
</form>

</body>
</html>


视图函数:reg

# forms组件
from django.forms import widgets

wid_01=widgets.TextInput(attrs={"class":"form-control"})
wid_02=widgets.PasswordInput(attrs={"class":"form-control"})

class UserForm(forms.Form):
    name=forms.CharField(max_length=32,
                         widget=wid_01
                         )
    pwd=forms.CharField(max_length=32,widget=wid_02)
    r_pwd=forms.CharField(max_length=32,widget=wid_02)
    email=forms.EmailField(widget=wid_01)
    tel=forms.CharField(max_length=32,widget=wid_01)



def register(request):

    if request.method=="POST":
        form=UserForm(request.POST)  # 生成校验对象,接受客户端传过来的值,进行校验
        if form.is_valid():  # 返回布尔值,校验的最后结果
            print(form.cleaned_data)       # 所有通过校验的字段以及对应的值
        else:
            print(form.cleaned_data)       #
            print(form.errors)             # ErrorDict : {"校验错误的字段":["错误信息",]}
            print(form.errors.get("name")) # ErrorList ["错误信息",]
        return HttpResponse("OK")
 
    return render(request,"register.html",locals())


重要的点:

模板传过来的字段要和类的字段一一对应。

可以多,不能少。

如果有没有的值,即多了不存在字段,不会报错,不care没有的键值对。但是,若少了必然会是False

默认都有非空规则,如果需要的匹配的值,有找不到的,就会是False。

如果全部正确,才是True

如果有错误的,正确的放在form.cleaned_data,错误的放在forms.errors ,错误的信息作为值

forms.error.get(“xxx”)[0]取出错误信息,因为其本质的类型是一个字典

form.is_valid() :返回布尔值
form.cleaned_data :{"name":"yuan","email":"123@qq.com"}
form.errors :{"name":[".........."]}

渲染标签功能

为了更方便和快捷,以及防止输入出错,我么可以使用标签渲染


方式一

form=UserForm

{{form.字段名.lable }}

{{form.字段名 }}

需要在Form类中设置lable属性,显示别名(中文名)

view.py中

class UserForm(forms.Form):
    name=forms.CharField(min_length=4,label='用户名')
    pwd=forms.CharField(min_length=4,label='密码')
    pwd_r=forms.CharField(min_length=4,label='确认密码')
    tel=forms.CharField(label='手机号')
    email=forms.EmailField(label='邮箱')

reg.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
   <!-- 最新版本的 Bootstrap 核心 CSS 文件 -->
    <link rel="stylesheet" href="https://cdn.bootcss.com/bootstrap/3.3.7/css/bootstrap.min.css" integrity="sha384-BVYiiSIFeK1dGmJRAkycuHAHRg32OmUcww7on3RYdg4Va+PmSTsz/K68vbdEjh4u" crossorigin="anonymous">
</head>
<body>
<h3>注册页面</h3>
<div class="container">
    <div class="row">
        <div class="col-md-6 col-lg-offset-3">

                <form action="" method="post">
                    {% csrf_token %}
                    <div>
                        <label for="">用户名</label>
                        {{ form.name }}
                    </div>
                    <div>
                        <label for="">密码</label>
                        {{ form.pwd }}
                    </div>
                    <div>
                        <label for="">确认密码</label>
                        {{ form.r_pwd }}
                    </div>
                    <div>
                        <label for=""> 邮箱</label>
                        {{ form.email }}
                    </div>

                    <input type="submit" class="btn btn-default pull-right">
                </form>
        </div>
    </div>
</div>



</body>
</html>


方式二

用for循环动态添加

<form action="" method="post">
                    {% csrf_token %}
                    
                    {% for field in form %}
                        <div>
                            <label for="">{{ field.label }}</label>
                            {{ field }}
                        </div>
                    {% endfor %}
                    <input type="submit" class="btn btn-default pull-right">
                
</form>


方式三

{{form.as_p }},{{ forms.as_table }},….有很多种

固定了样式,而且不易于操作,所以不建议使用

<form action="" method="post">
    {% csrf_token %}
    
    {{ form.as_p }}
    <input type="submit" class="btn btn-default pull-right">

</form>


显示错误与重置输入信息功能

views.py

from django.shortcuts import render

# Create your views here.
from app01.models import *
from django import forms
from django.forms import widgets  # 设置调整渲染的样式的模块


# 创建forms组件,用来校验输入
class UserForm(forms.Form):
    name=forms.CharField(min_length=4, # 校验长度
                         label='用户名',   # 设置别名
                         error_messages={"required":'该字段不能为空'},  # 错误信息提示更改为中文
                         widget=widgets.TextInput(attrs={'class':'form-control'}))  # 添加class类的样式
    pwd=forms.CharField(min_length=4,label='密码',
                        widget=widgets.PasswordInput(attrs={'class':'form-control'}),  # 设置成password类型,并添加样式
                        error_messages = {"required": '该字段不能为空'}
                        )
    pwd_r=forms.CharField(min_length=4,label='确认密码',
                          error_messages={"required":'该字段不能为空'},
                          widget=widgets.TextInput(attrs={'class':'form-control'})
                          )
    tel=forms.CharField(label='手机号',
                        error_messages={"required":'该字段不能为空','invalid':'格式错误'},
                        widget=widgets.TextInput(attrs={'class':'form-control'})
                        )
    email=forms.EmailField(label='邮箱',

                           error_messages={"required":'该字段不能为空','invalid':'格式错误'},
                           widget=widgets.TextInput(attrs={'class':'form-control'})
                           )


def reg(request):
    if request.method=="POST":
        forms=UserForm(request.POST)
        print('post')
        if forms.is_valid():
            print(forms.cleaned_data)
        else:
            print(forms.is_valid())
            print(forms.cleaned_data)
            print(forms.errors)
            # 重要的一步放在这里,同时保留了传过来的值,所以前端在刷新的时候,之前的输入还会存在
            return render(request,'reg.html',locals())

    forms=UserForm()

    return render(request,'reg.html',locals())

                                                                                                                                     

模板reg.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <link rel="stylesheet" href="https://cdn.bootcss.com/bootstrap/3.3.7/css/bootstrap.min.css"
          integrity="sha384-BVYiiSIFeK1dGmJRAkycuHAHRg32OmUcww7on3RYdg4Va+PmSTsz/K68vbdEjh4u" crossorigin="anonymous">
</head>
<body>
    <h3>渲染方式一</h3>
    <form action="" method="post" novalidate>
        {% csrf_token %}
        <p>
            {{ forms.name.label }}{{ forms.name }}
            <span>{{ forms.name.errors.0 }}</span>
        </p>
        <p>
            {{ forms.pwd.label }}{{ forms.pwd }}
            <span>{{ forms.pwd.errors.0 }}</span> {#.0很重要 取到第一个错误,errors得到的是一个li标签列表#}
        </p>
        <p>
            {{ forms.pwd_r.label }}{{ forms.pwd_r }}
            <span>{{ forms.pwd_r.errors.0 }}</span> {#.0很重要#}
        </p>
        <p>
            {{ forms.tel.label }}{{ forms.tel }}
            <span>{{ forms.tel.errors.0 }}</span> {#.0很重要#}
        </p>
        <p>
            {{ forms.email.label }}{{ forms.email }}
            <span>{{ forms.email.errors.0 }}</span> {#.0很重要#}
        </p>
            <input type="submit">
    </form>
</body>
</html>


局部钩子与全局钩子

模板文件reg.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        .error{
            color: red;
        }
    </style>
    <!-- 最新版本的 Bootstrap 核心 CSS 文件 -->
    <link rel="stylesheet" href="https://cdn.bootcss.com/bootstrap/3.3.7/css/bootstrap.min.css"
    integrity="sha384-BVYiiSIFeK1dGmJRAkycuHAHRg32OmUcww7on3RYdg4Va+PmSTsz/K68vbdEjh4u" crossorigin="anonymous">
</head>
<body>

<div class="container">

    <div class="row">
        <div class="col-md-6 col-lg-offset-3">
            <hr>
            <h3>forms组件渲染方式1</h3>
            <form action="" method="post" novalidate>
                {% csrf_token %}
                <p>{{ form.name.label }}
                    {{ form.name }} <span class="pull-right error">{{ form.name.errors.0 }}</span>
                </p>
                <p>{{ form.pwd.label }}
                    {{ form.pwd }} <span class="pull-right error">{{ form.pwd.errors.0 }}</span>
                </p>
                <p>确认密码
                    {{ form.r_pwd }} <span class="pull-right error">{{ form.r_pwd.errors.0 }}</span>
                    <span class="pull-right error">{{ errors.0 }}</span>  {# 全局错误 #}
                </p>
                <p>邮箱 {{ form.email }} <span class="pull-right error">{{ form.email.errors.0 }}</span></p>
                <p>手机号 {{ form.tel }} <span class="pull-right error">{{ form.tel.errors.0 }}</span></p>
                <input type="submit">

            </form>
        </div>
    </div>
</div>

</body>
</html>


视图函数views.py

from django.shortcuts import render,HttpResponse

# Create your views here.

from app01.myforms import *


def reg(request):

    if request.method=="POST":

        print(request.POST)

        #form=UserForm({"name":"yu","email":"123@qq.com","xxxx":"alex"})


        form=UserForm(request.POST) # form表单的name属性值应该与forms组件字段名称一致

        print(form.is_valid()) # 返回布尔值

        if form.is_valid():
            print(form.cleaned_data)  # {"name":"yuan","email":"123@qq.com"}
        else:
            print(form.cleaned_data)  # {"email":123@qq.com}


            #   全局钩子错误
            #print("error",form.errors.get("__all__")[0])
            errors=form.errors.get("__all__")

            return render(request,"reg.html",locals())

    form=UserForm()

    return render(request,"reg.html",locals())


将forms组件逻辑,新建文件单独放置

from django import forms

from django.forms import widgets
from app01.models import UserInfo

from django.core.exceptions import NON_FIELD_ERRORS, ValidationError

class UserForm(forms.Form):
    name=forms.CharField(min_length=4,label="用户名",error_messages={"required":"该字段不能为空"},
                         widget=widgets.TextInput(attrs={"class":"form-control"})
                         )
    pwd=forms.CharField(min_length=4,label="密码",
                        widget=widgets.PasswordInput(attrs={"class":"form-control"})
                        )
    r_pwd=forms.CharField(min_length=4,label="确认密码",error_messages={"required":"该字段不能为空"},widget=widgets.TextInput(attrs={"class":"form-control"}))
    email=forms.EmailField(label="邮箱",error_messages={"required":"该字段不能为空","invalid":"格式错误"},widget=widgets.TextInput(attrs={"class":"form-control"}))
    tel=forms.CharField(label="手机号",widget=widgets.TextInput(attrs={"class":"form-control"}))


    def clean_name(self):  # 局部钩子

        val=self.cleaned_data.get("name")

        ret=UserInfo.objects.filter(name=val)

        if not ret:
            return val
        else:
            raise ValidationError("该用户已注册!")

    def clean_tel(self):  # 局部钩子

        val=self.cleaned_data.get("tel")

        if len(val)==11:

            return val
        else:
            raise  ValidationError("手机号格式错误")

    def clean(self):  # 全局钩子
        pwd=self.cleaned_data.get('pwd')
        r_pwd=self.cleaned_data.get('r_pwd')

        if pwd and r_pwd:
            if pwd==r_pwd:
                return self.cleaned_data
            else:
                raise ValidationError('两次密码不一致')
        else:

            return self.cleaned_data
原文地址:https://www.cnblogs.com/yxiaodao/p/9550560.html