Python 烧瓶表单类型错误：类型为'的对象；int'；没有len（）

我想用flask做一份登记表。我的代码看起来很干净，显示了所有正确的数据类型。该错误还强调了my

routes.py

中的

if form.validate\u on_submit（）：

。我现在迷路了，我真的不知道该怎么办

编辑：我需要它来成功发布数据。请帮帮我

路线：

from flask import render_template, url_for, flash, redirect
from registration import main
from registration.forms import RegistrationForm
from registration.models import Student, Colleges

@main.route("/")
def index():
    return redirect(url_for('register'))
@main.route("/register", methods=['GET','POST'])
def register():
    form = RegistrationForm()
    form.college.choices = [(c.id, c.college) for c in Colleges.query.all()]

    if form.validate_on_submit():
        college = Colleges.query.filter_by(college=form.college.data).first()
        reg_student = Student(student_number=form.student_number.data,last_name=form.last_name.data,first_name=form.first_name.data,college=college.id,section=form.section.data,email=form.email.data)
        db.session.add(reg_student)
        db.session.commit()

    return render_template('register.html', form=form)

@main.route("/admin")
def admin():
    return "Students list"

{% extends "base.html" %}

{% block content %}

{{ form.hidden_tag() }}
<form method="POST">
  <fieldset>
    <legend>Register:</legend>
    {{ form.student_number.label }}
    {{ form.student_number(class="form-control form-control-lg") }} 

    {{ form.last_name.label }}
    {{ form.last_name(class="form-control form-control-lg") }} 

    {{ form.first_name.label }}
    {{ form.first_name(class="form-control form-control-lg") }} 

    {{ form.college.label }}
    {{ form.college(class="form-control form-control-lg") }} 


    {{ form.section.label }}
    {{ form.section(class="form-control form-control-lg") }} 

    {{ form.email.label }}
    {{ form.email(class="form-control form-control-lg") }} 

    {{ form.submit(class="btn btn-outline-info") }}

  </fieldset>

</form>

{% endblock %}

型号：

from registration import db

class Colleges(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    college = db.Column(db.String(120), nullable=False)
    students = db.relationship('Student', backref='department', lazy=True)


    def __repr__(self):
        return f"College('{self.college}')"

class Student(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    student_number = db.Column(db.String(11), unique=True,nullable=False)
    last_name = db.Column(db.String(60), nullable=False)
    first_name = db.Column(db.String(60), nullable=False)
    college_id = db.Column(db.Integer, db.ForeignKey('colleges.id'), nullable=False)
    section = db.Column(db.String(10), nullable=False)
    email = db.Column(db.String(120), unique=True, nullable=False)

    def __repr__(self):
        return f"Student('{self.student_number}','{self.last_name}','{self.first_name}','{self.college_id}','{self.section}','{self.email}')"

from flask_wtf import FlaskForm
from wtforms import StringField, PasswordField, SubmitField, BooleanField, IntegerField, SelectField
from wtforms.validators import DataRequired, Length, Email, EqualTo


class RegistrationForm(FlaskForm):
    student_number = IntegerField('Student Number', validators=[DataRequired(),Length(min=11,max=11)])
    last_name = StringField('Last Name',validators=[DataRequired()])
    first_name = StringField('First Name',validators=[DataRequired()])
    college = SelectField('College', coerce=int,validators=[DataRequired()])
    section = StringField('Section', validators=[DataRequired()])
    email = StringField('Email', validators=[DataRequired(), Email()])
    submit = SubmitField('Sign Up')

表格：

from registration import db

class Colleges(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    college = db.Column(db.String(120), nullable=False)
    students = db.relationship('Student', backref='department', lazy=True)


    def __repr__(self):
        return f"College('{self.college}')"

class Student(db.Model):
    id = db.Column(db.Integer, primary_key=True)
    student_number = db.Column(db.String(11), unique=True,nullable=False)
    last_name = db.Column(db.String(60), nullable=False)
    first_name = db.Column(db.String(60), nullable=False)
    college_id = db.Column(db.Integer, db.ForeignKey('colleges.id'), nullable=False)
    section = db.Column(db.String(10), nullable=False)
    email = db.Column(db.String(120), unique=True, nullable=False)

    def __repr__(self):
        return f"Student('{self.student_number}','{self.last_name}','{self.first_name}','{self.college_id}','{self.section}','{self.email}')"

from flask_wtf import FlaskForm
from wtforms import StringField, PasswordField, SubmitField, BooleanField, IntegerField, SelectField
from wtforms.validators import DataRequired, Length, Email, EqualTo


class RegistrationForm(FlaskForm):
    student_number = IntegerField('Student Number', validators=[DataRequired(),Length(min=11,max=11)])
    last_name = StringField('Last Name',validators=[DataRequired()])
    first_name = StringField('First Name',validators=[DataRequired()])
    college = SelectField('College', coerce=int,validators=[DataRequired()])
    section = StringField('Section', validators=[DataRequired()])
    email = StringField('Email', validators=[DataRequired(), Email()])
    submit = SubmitField('Sign Up')

register.html:

from flask import render_template, url_for, flash, redirect
from registration import main
from registration.forms import RegistrationForm
from registration.models import Student, Colleges

@main.route("/")
def index():
    return redirect(url_for('register'))
@main.route("/register", methods=['GET','POST'])
def register():
    form = RegistrationForm()
    form.college.choices = [(c.id, c.college) for c in Colleges.query.all()]

    if form.validate_on_submit():
        college = Colleges.query.filter_by(college=form.college.data).first()
        reg_student = Student(student_number=form.student_number.data,last_name=form.last_name.data,first_name=form.first_name.data,college=college.id,section=form.section.data,email=form.email.data)
        db.session.add(reg_student)
        db.session.commit()

    return render_template('register.html', form=form)

@main.route("/admin")
def admin():
    return "Students list"

{% extends "base.html" %}

{% block content %}

{{ form.hidden_tag() }}
<form method="POST">
  <fieldset>
    <legend>Register:</legend>
    {{ form.student_number.label }}
    {{ form.student_number(class="form-control form-control-lg") }} 

    {{ form.last_name.label }}
    {{ form.last_name(class="form-control form-control-lg") }} 

    {{ form.first_name.label }}
    {{ form.first_name(class="form-control form-control-lg") }} 

    {{ form.college.label }}
    {{ form.college(class="form-control form-control-lg") }} 


    {{ form.section.label }}
    {{ form.section(class="form-control form-control-lg") }} 

    {{ form.email.label }}
    {{ form.email(class="form-control form-control-lg") }} 

    {{ form.submit(class="btn btn-outline-info") }}

  </fieldset>

</form>

{% endblock %}

{%extends“base.html”%}
{%block content%}
{{form.hidden_tag（）}}
登记册：
{{form.student_number.label}
{{form.student_number（class=“form control form control lg”）}
{{form.last_name.label}
{{form.last_name（class=“form control form control lg”）}
{{form.first_name.label}
{{form.first_name（class=“form control form control lg”）}
{{form.college.label}
{{form.college（class=“form control form control lg”）}
{{form.section.label}
{{form.section（class=“form control form control lg”）}
{{form.email.label}
{{form.email（class=“form control form control lg”）}
{{form.submit（class=“btn btn outline info”）}
{%endblock%}

我还没有试过使用烧瓶。如果我错了，请纠正我。 我认为问题在于RegistrationForm（）类下面的这一行：

---

检查后，wtforms.validators.Length（）将验证字符串，但您正在IntegerField（）上使用此验证器。尝试改用StringField（）。

我还没有尝试使用Flask。如果我错了，请纠正我。 我认为问题在于RegistrationForm（）类下面的这一行：

---

检查后，wtforms.validators.Length（）将验证字符串，但您正在IntegerField（）上使用此验证器。尝试改用StringField（）。

更改了它，显然它仍然不起作用。虽然在服务器日志中，它说它已进行了后期更改，但显然它仍然不起作用。虽然在服务器日志中显示POST