Flask-WTF实例化嵌套表单

from flask_wtf import FlaskForm
from wtforms import StringField, IntegerField, FieldList, FormField, SubmitField
from wtforms.validators import DataRequired

class OrderItemForm(FlaskForm):
    product_name = StringField('Product Name', validators=[DataRequired()])
    quantity = IntegerField('Quantity', validators=[DataRequired()])

class OrderForm(FlaskForm):
    customer_name = StringField('Customer Name', validators=[DataRequired()])
    order_items = FieldList(FormField(OrderItemForm), min_entries=1)
    submit = SubmitField('Submit')

from flask import Flask, render_template, redirect, url_for
app = Flask(__name__)
app.config['SECRET_KEY'] = 'your_secret_key'

@app.route('/order', methods=['GET', 'POST'])
def order():
    form = OrderForm()
    if form.validate_on_submit():
        # 处理表单数据
        customer_name = form.customer_name.data
        for item in form.order_items.data:
            product_name = item['product_name']
            quantity = item['quantity']
            # 保存订单项
        return redirect(url_for('success'))
    return render_template('order.html', form=form)

@app.route('/success')
def success():
    return 'Order submitted successfully!'

if __name__ == '__main__':
    app.run(debug=True)

<!-- order.html -->
<form method="POST">
    {{ form.hidden_tag() }}
    <p>
        {{ form.customer_name.label }}<br>
        {{ form.customer_name(size=32) }}
    </p>
    {% for item in form.order_items %}
        <p>
            {{ item.product_name.label }}<br>
            {{ item.product_name(size=32) }}
        </p>
        <p>
            {{ item.quantity.label }}<br>
            {{ item.quantity(size=32) }}
        </p>
    {% endfor %}
    <p>{{ form.submit() }}</p>
</form>

if form.validate_on_submit():
    # 确保每个子表单字段都通过验证
    for item in form.order_items.data:
        if not item['product_name'] or not item['quantity']:
            form.order_items.errors.append('Invalid data')
            break