How do I correctly submit results from a wtformusing Jinja with a Python /Flask setup

问题

What I'm trying to do

Instead of using form.predictions() I've tried to separate it out so I can style it better, although it doesn't work when I submit the predictions apart from the first prediction..i.e doesn't update it apart from the first one.

I don't really want to write them all out hence the for loop and loop.index

Issue

Say if update one row of scores, it does not update the db, although I get a flash message saying I have. Strangely only row 1 works and the others dont.

views

# Predictor - User makes predictions and saves/
@app.route('/predictor/',methods=['GET','POST'])
@login_required
def predictions():
    user_id = g.user.id
    # retrieve predictions
    prediction= db.session.query(Fixture_prediction,\
                Fixture_prediction.fixture_id,Fixture.stage,\
                Fixture.home_team,Fixture_prediction.home_score,\
                Fixture_prediction.away_score,Fixture.away_team)\
                .outerjoin(Fixture,Fixture.id==Fixture_prediction.fixture_id)\
                .filter(Fixture_prediction.fixture_id==Fixture.id)\
                .filter(Fixture_prediction.user_id==user_id).all()
    data = {'predictions': prediction}
    form = PredictionListForm(request.form,data=MultiDict(data))
    if request.method == 'POST':
        for prediction in form.predictions:
            store=db.session.query(Fixture_prediction) \
                .filter(Fixture_prediction.user_id==user_id) \
                .filter(Fixture_prediction.fixture_id==prediction.fixture_id.data)\
                .update({'home_score':prediction.home_score.data\
                ,'away_score':prediction.away_score.data})
            db.session.commit()
            flash('Prediction added')
            return redirect(url_for('predictions'))
    # display current predictions
    elif request.method == 'GET':
        return render_template('predictor.html', form=form)

template

<form action='' method='post'>
    <table>
     <tr>
      <th>Fixture Id</th>
      <th>Stage</th>
      <th>Home Team</th>
      <th>Home Score</th>
      <th>Away Score</th>
      <th>Away Team</th>
     </tr>
     {%for prediction in form.predictions%}
     <tr>
  <td><input name="predictions-{{loop.index0}}-fixture_id" type="text" value={{prediction.fixture_id.data}}></td>
  <td><input name="predictions-{{loop.index0}}-stage" type="text" value="{{prediction.stage.data}}"></td>
  <td><input name="predictions-{{loop.index0}}-home_team" type="text" value={{prediction.home_team.data}}></td>
  <td><input name="predictions-{{loop.index0}}-home_score" type="text" value={{prediction.home_score.data}}></td>
  <td><input name="predictions-{{loop.index0}}-away_score" type="text" value={{prediction.away_score.data}}></td>
  <td><input name="predictions-{{loop.index0}}-away_team" type="text" value={{prediction.away_team.data}}></td>
 </tr>
 {%endfor%}
</table>
<p><input type="submit" value="Submit Predictions"></p>
</form>

回答1:

I believe the problem is in this block of code:

if request.method == 'POST':
    for prediction in form.predictions:
        store=db.session.query(Fixture_prediction) \
            .filter(Fixture_prediction.user_id==user_id) \
            .filter(Fixture_prediction.fixture_id==prediction.fixture_id.data)\
            .update({'home_score':prediction.home_score.data\
            ,'away_score':prediction.away_score.data})
        db.session.commit()
        flash('Prediction added')
        return redirect(url_for('predictions'))

The problem is after the first iteration of your for loop, you commit your changes, flash a message and redirect. These three statements need to be outside the for loop like below:

if request.method == 'POST':
    for prediction in form.predictions:
        store=db.session.query(Fixture_prediction) \
            .filter(Fixture_prediction.user_id==user_id) \
            .filter(Fixture_prediction.fixture_id==prediction.fixture_id.data)\
            .update({'home_score':prediction.home_score.data\
            ,'away_score':prediction.away_score.data})
    db.session.commit()
    flash('Prediction added')
    return redirect(url_for('predictions'))

来源：https://stackoverflow.com/questions/24160335/how-do-i-correctly-submit-results-from-a-wtformusing-jinja-with-a-python-flask