How to get the Jinja2 generated input value data?

Question

In my HTML file, I have:

  <table>
      {% for user in user_data_html %}
      <tr>
         <td>
            <input id="firstname" name="firstname" type="text" value='{{ user.FirstName }}' />  
         </td>
         <td>
             <input name="submit" type="submit" value='update' />
         </td>
     </tr>
     {% else %}
     <tr><td>no user found</td></tr>
     {% endfor %}
 </table>

I want to modify the user name in the webpage by clicking update button in each row. But I always get the first "firstname" using the following python code in the backend:

firstname = request.form['firstname']

How can I solve this problem?

Solution 1

Forms get confused when you use the same name for each input name. You could either create a separate form around each table cell with the first name or you can use the jinja2 loop index to create unique input names...

<input id="firstname{{ loop.index }}" name="firstname{{ loop.index }}" type="text" value='{{ user.FirstName }}' />

Hope this helps!

Solution 2

request.form is a werkzeug.datastructures.MultiDict. You can get out all the values for a field with its getlist method:

a_firstname = request.form['firstname']
all_firstnames = request.form.getlist('firstname')

If you need the names to be in the order they were defined in the form you need to subclass flask.Request and set its parameter_storage_class to an instance of ImmutableOrderedMultiDict. Then you need to set the request_class field on your Flask instance:

from flask import Flask, Request
from werkzeug.datastructures import ImmutableOrderedMultiDict

class OrderedRequest(Request):
    parameter_storage_class = ImmutableOrderedMultiDict

app = Flask(__name__)
app.request_class = OrderedRequest

Then request.form.getlist('firstname') will return the fields in the order the browser sent them (which is conventionally in the order they are defined in the HTML).