提交后如何将字段值保留在表单中? [英] How can I keep field values in a form after submit?
问题描述
提交表单后,似乎字段值未设置为空.我正在做一些表格验证;如果表单无效,我将显示错误列表中的错误消息,但我希望保留字段值.有办法吗?
After submitting a form it appears that the field values are set back to nothing. I am doing some form validation; if the form is invalid I am having it display an error message from a list of errors but I wish for the field values to stay. Is there a way to do this?
这是我验证表单的视图:
This is my view that validates the form:
@app.route('/booking', methods=['GET', 'POST'])
def booking():
errors = []
if request.method == 'GET':
return render_template('booking.html', errors=errors)
else:
# grab values from form fields and store them in objects
start_date = request.form['start_date']
end_date = request.form['end_date']
name = request.form['name'].strip()
email = request.form['email'].strip()
# check if all fields are non-empty and raise an error if not
if not start_date or not end_date or not name or not email:
errors.append('Please enter all the fields.')
else:
# converts dates to Unix time-stamp for easier validation/calculations
start_timestamp = dt.strptime(start_date, "%d/%m/%Y")
end_timestamp = dt.strptime(end_date, "%d/%m/%Y")
# checks to see if dates are valid
if start_timestamp > end_timestamp or end_timestamp < start_timestamp:
errors.append('Please enter a valid date range')
else:
#checks to see if booking has already been taken
bookings = read_file('app/static/bookings.csv')
for i in bookings:
s_date = dt.strptime(i[0], "%d/%m/%Y")
e_date = dt.strptime(i[1], "%d/%m/%Y")
if s_date <= start_timestamp <= e_date:
errors.append('Booking has already been taken, please select another date')
break
# checks to see if email address is valid using regex
if not valid_email_address(email):
errors.append('Please enter a valid email address')
#if no errors have occured then write booking to file
if not errors:
new_booking = [start_date, end_date, name, email]
bookings.append(new_booking)
write_file(bookings, 'app/static/bookings.csv')
return render_template('booking.html')
return render_template('booking.html', errors=errors)
这是表单的模板:
<div id="main-wrapper">
<div id="main">
<div id="info">
{% if errors %}
{% for error in errors %}
<div><p>{{ error }}</p></div>
{% endfor %}
{% endif %}
<form action = "booking" method="post">
<input id="start_date" type="text" name="start_date">
<input id="end_date" type="text" name="end_date">
<input type="text" name="name" />
<input type="text" name="email" />
<input type="submit" value="Submit">
</div>
</div>
</div>
推荐答案
最好使用诸如 WTForms (以及相关的扩展名 Flask-WTF ),而不是手动完成所有操作.
You'd be better off using a form library such as WTForms (and the associated extension Flask-WTF) instead of doing this all manually.
但是,如果您设置了此方法,那么它很简单.您需要将request.form的值提供给HTML输入.
But if you're set on this method, then it's pretty traightforward. You need to provide the value from request.form to the HTML inputs.
<input id="start_data" type="text" name="start_date" value="{{ request.form['start_date'] }}"/>
这篇关于提交后如何将字段值保留在表单中?的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!