6.2.用form实现登录

表单校验

定义表单

users/forms.py

from django import forms


class LoginForm(forms.Form):
    username = forms.CharField(required=True)
    password = forms.CharField(required=True, min_length=5)

通过表单的is_valid()方法验证表单是否有效

users/views.py

class LoginView(View):
    def get(self, request):
        return render(request, 'login.html', {})

    def post(self, request):
        login_form = LoginForm(request.POST)
        if login_form.is_valid():
            username = request.POST.get('username')
            password = request.POST.get('password')
            user = authenticate(username=username, password=password)
            if user is not None:
                login(request, user)
                return render(request, 'index.html', {})
            else:
                return render(request, 'login.html', {'msg': '用户名或密码错误'})
        else:
            return render(request, 'login.html', {'login_form': login_form})

显示错误信息到前台

判断是否有错

<div class="form-group marb20 {% if  login_form.errors.username %}errorput{% endif %} " >

获取错误信息

{% for key,error in login_form.errors.items %}{{ key }}:{{ error }}{% endfor %}

完整示例

templates/login.html

<form action="{% url 'login' %}" method="post" autocomplete="off">
    <input type='hidden' name='csrfmiddlewaretoken' value='mymQDzHWl2REXIfPMg2mJaLqDfaS1sD5'/>
    <div class="form-group marb20 {% if  login_form.errors.username %}errorput{% endif %} " >
        <label>用户名</label>
        <input name="username" id="account_l" type="text" placeholder="手机号/邮箱"/>
    </div>
    <div class="form-group marb8 {% if  login_form.errors.password %}errorput{% endif %} " >
        <label>密码</label>
        <input name="password" id="password_l" type="password" placeholder="请输入您的密码"/>
    </div>
    <div class="error btns login-form-tips" id="jsLoginTips">{% for key,error in login_form.errors.items %}{{ key }}:{{ error }}{% endfor %}{{ msg }}</div>
    <div class="auto-box marb38">

        <a class="fr" href="forgetpwd.html">忘记密码？</a>
    </div>
    <input class="btn btn-green" id="jsLoginBtn" type="submit" value="立即登录 > "/>
    {% csrf_token %}
</form>