Python 表单值未添加到Flask中的数据库

我早些时候发布了这个问题，但随后它被链接到一个类似的问题，该问题没有提供所需的解决方案，然后被关闭以供回答

因此，我创建了一个Flask应用程序，它跟踪产品从一个位置到另一个位置的移动，同时我通过Flask应用程序进行移动。表单没有得到验证。我尝试将

{{form.hidden_tag（）}

和

{form.csrf_token}

添加到接收用户输入的html文件中

如果我从命令行上的终端运行此应用程序，则表单将被验证并添加到数据库中，但如果我运行flask应用程序并在浏览器中提交表单，则表单不会被验证

这是我的代码

class MovementForm(FlaskForm):
    to_location = SelectField('To Location', coerce=int)
    from_location = SelectField('From Location', coerce=int)
    product = SelectField('Product')
    quantity = IntegerField('Quantity')
    add_movement = SubmitField('Add Movement')

@app.route('/movements',methods=["GET","POST"])
def add_movements():
    form = MovementForm()
    form.to_location.choices = [(location.id, location.location_name) for location in Location.query.all()]
    form.from_location.choices = [(location.id, location.location_name) for location in Location.query.all()]
    form.product.choices = [(product.id, product.product_name) for product in Product.query.all()]
    form.from_location.choices.insert(0, (0, 'None'))   
    if form.validate_on_submit():
        new_movement = Movement(to_location_id=form.to_location.data, from_location_id=form.from_location.data, product_id=form.product.data, quantity=form.quantity.data)
        db.session.add(new_movement)
        db.session.commit()
        flash('Product has been moved!', 'success')
        return redirect(url_for('add_movements'))   
    return render_template('add_movements.html', form=form)

这是我的html文件

 <form action="/movements" method="post">
        {{ form.hidden_tag() }}
        {{ form.csrf_token }}
        <div class="row">
            <div class="form-group col">
                {{ form.from_location.label(class="form-control-label") }}
                {{ form.from_location(class="form-control form-control-lg") }}
            </div>
            <div class="form-group col">
                {{ form.to_location.label(class="form-control-label") }}
                {{ form.to_location(class="form-control form-control-lg") }}
            </div>
        </div>
        <div class="row">
            <div class="form-group col">
                {{ form.product.label(class="form-control-label") }}
                {{ form.product(class="form-control form-control-lg") }}
            </div>
            <div class="form-group col">
                {{ form.quantity.label(class="form-control-label") }}
                {{ form.quantity(class="form-control form-control-lg") }}
            </div>
        </div>
        <div class="form-group">
                {{ form.add_movement(class="btn btn-outline-info") }}
        </div>
    </form> 

{{form.hidden_tag（）}}
{{form.csrf_token}
{{form.from_location.label（class=“form control label”）}
{{form.from_location（class=“form control form control lg”）}
{{form.to_location.label（class=“form control label”）}
{{form.to_location（class=“form control form control lg”）}
{{form.product.label（class=“form control label”）}
{{form.product（class=“form control form control lg”）}
{{form.quantity.label（class=“form control label”）}
{{form.quantity（class=“form control form control lg”）}
{{form.add_movement（class=“btn btn outline info”）}

---

这里出了什么问题？

尝试删除以更改HTML表单中的表单操作

 <form action="" method="post">
    {{ form.hidden_tag() }}
    {{ form.csrf_token }}
    <div class="row">
        <div class="form-group col">
            {{ form.from_location.label(class="form-control-label") }}
            {{ form.from_location(class="form-control form-control-lg") }}
        </div>
        <div class="form-group col">
            {{ form.to_location.label(class="form-control-label") }}
            {{ form.to_location(class="form-control form-control-lg") }}
        </div>
    </div>
    <div class="row">
        <div class="form-group col">
            {{ form.product.label(class="form-control-label") }}
            {{ form.product(class="form-control form-control-lg") }}
        </div>
        <div class="form-group col">
            {{ form.quantity.label(class="form-control-label") }}
            {{ form.quantity(class="form-control form-control-lg") }}
        </div>
    </div>
    <div class="form-group">
            {{ form.add_movement(class="btn btn-outline-info") }}
    </div>
</form> 

---

编辑#2

---

如果您遇到此类问题（这种情况经常发生），我建议您添加一个print语句和一个If/Else子句。这将极大地帮助你找到问题所在（你发布的问题类型是你“看不见”），并会给你“眼睛”

例如，我会这样做：

@app.route('/movements',methods=["GET","POST"])
def add_movements():

    form = MovementForm()
    form.to_location.choices = [(location.id, location.location_name) for 
    location in Location.query.all()]
    form.from_location.choices = [(location.id, location.location_name) 
    for location in Location.query.all()]
    form.product.choices = [(product.id, product.product_name) for product 
    in Product.query.all()]
    form.from_location.choices.insert(0, (0, 'None')) 

    if form.validate_on_submit():
        print('Form Ok') #if you see the 'Form ok' to see if is validated
        new_movement = Movement(to_location_id=form.to_location.data, 
        from_location_id=form.from_location.data, 
        product_id=form.product.data, quantity=form.quantity.data)
        db.session.add(new_movement)
        db.session.commit()
        flash('Product has been moved!', 'success')
        return redirect(url_for('add_movements'))
     else:
         print('Form Not Ok') #If you see this printed then you see that 
          #is not validated

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

---

不，它没有，值仍然没有反映在数据库中。如果添加此flash消息，您可以在浏览器上看到flash消息吗？产品字段中的“强制”参数起作用。非常感谢。我认为问题在于表单返回false，因此在'if form.validate_on_submit（）：'之后的所有内容都返回false，因为它从不运行

class MovementForm(FlaskForm):
    to_location = SelectField('To Location', coerce=int)
    from_location = SelectField('From Location', coerce=int)
    product = SelectField('Product', coerce=int)
    quantity = IntegerField('Quantity')
    add_movement = SubmitField('Add Movement')

@app.route('/movements',methods=["GET","POST"])
def add_movements():

    form = MovementForm()
    form.to_location.choices = [(location.id, location.location_name) for 
    location in Location.query.all()]
    form.from_location.choices = [(location.id, location.location_name) 
    for location in Location.query.all()]
    form.product.choices = [(product.id, product.product_name) for product 
    in Product.query.all()]
    form.from_location.choices.insert(0, (0, 'None')) 

    if form.validate_on_submit():
        print('Form Ok') #if you see the 'Form ok' to see if is validated
        new_movement = Movement(to_location_id=form.to_location.data, 
        from_location_id=form.from_location.data, 
        product_id=form.product.data, quantity=form.quantity.data)
        db.session.add(new_movement)
        db.session.commit()
        flash('Product has been moved!', 'success')
        return redirect(url_for('add_movements'))
     else:
         print('Form Not Ok') #If you see this printed then you see that 
          #is not validated

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