forms组件

一,校验字段功能

-forms是什么?

		就是一个类,可以校验字段(前台传过来的字段)
	-怎么用:

针对一个实例:注册用户讲解。

模型:models.py

 

class UserInfo(models.Model):      # 写一个类,要校验那些字段,就是类的属性
    name=models.CharField(max_length=32)  # 定义一个属性,可以用来校验字符串类型
    pwd=models.CharField(max_length=32)
    email=models.EmailField()

模板文件里:

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

</head>
<body>

<form action="" method="post">
    {% csrf_token %}
    <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>

视图函数里:

# forms组件
from django.forms import widgets

wid_01=widgets.TextInput(attrs={"class":"form-control"})      #控制input输入框的格式,括号里面是控制的样式
wid_02=widgets.PasswordInput(attrs={"class":"form-control"})   #控制密码框,这样密码就是密文格式

class UserForm(forms.Form):             #重写一个类
    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)    #实例化出来一个对象,#实例化产生对象,传入要校验的数据(字典)
        if form.is_valid():   #判断is_valid如果是true,校验成功
            print(form.cleaned_data)       # 所有干净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")
    form=UserForm()
    return render(request,"register.html",locals())
    -注意:校验的字段,可以多,但是不能少

二 渲染标签功能

渲染方式一:

<!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>

渲染方式2

<h1>第二种方式(for循环form对象,建议用这种)</h1>
<form action="" method="post" >
    {% for foo in myform %}
        <p>{{ foo.label }}:{{ foo }}</p>
    {% endfor %}

    <input type="submit" value="提交">
</form>

渲染方式3

<h1>第三种方式(不建议用)</h1>
<form action="" method="post" >

{#    {{ myform.as_p }}#}
    {{ myform.as_ul }}
    <input type="submit" value="提交">
</form>
</body>
</html>

三渲染错误信息功能

  • myforms有errors
    -属性(name)也有errors
    -错误信息,变成中文:

视图里:

def register(request):

    if request.method=="POST":
        form=UserForm(request.POST)
        if form.is_valid():
            print(form.cleaned_data)       # 所有干净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 render(request,"register.html",locals())
    form=UserForm()
    return render(request,"register.html",locals())

模板里:

<form action="" method="post" novalidate>
    {% for foo in myform %}     #循环出来的是要校验的字段
        <p>{{ foo.label }}:{{ foo }} <span>{{ foo.errors.0 }}</span></p>
    {% endfor %}

    <input type="submit" value="提交"><span>{{ all_error }}</span>
</form>

四 局部钩子:

-定义一个函数,名字叫:clean_字段名字,内部,取出该字段,进行校验,如果通过,将该字段返回,如果失败,抛异常(ValidationError)

from django.core.exceptions import NON_FIELD_ERRORS, ValidationError
def clean_name(self):

        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):

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

        if len(val)==11:

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

五 全局钩子:

#重写clean方法

 def clean(self):
        #程序能走到该函数,前面校验已经通过了,所以可以从cleaned_data中取出密码和确认密码	
        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/fxc-520520/p/9997572.html