Python Retaining variables from a text box.

[Ramone]

My issue is this. I can retrieve the chosenclass variable from the html text box, and the classroom of students is displayed, but after the updatepa function is called, that is after a student record has been updated, the variable is reset to the initial value of " " and so no class is displayed in the form.

I need a way of retaining the value of chosenclass. I'm thinking flask g or session might work but I'm not really sure how to implement this in my code. Or is there a better way of retaining a variable?

@app.route('/' , methods = ["GET", "POST"])
def Index():
        chosenclass = request.values.get('chosenclass')
        all_data = Data.query.filter_by(classroom=chosenclass).all()
        return render_template("index.html", students = all_data)

@app.route('/updatepa', methods = ['GET', 'POST'])

def updatepa():
    if request.method == 'POST':
        my_data = Data.query.get(request.form.get('id'))
        my_data.name = request.form['name']
        my_data.studentid = request.form['studentid']
        my_data.classroom = request.form['classroom']
        my_data.classtime = request.form['classtime']
        my_data.pacomment = request.form['pacomment']

        db.session.commit()
        flash("Student Updated Successfully")
        return redirect(url_for('Index'))

I have tried chosenclass = request.g.get('chosenclass') but receive the error message AttributeError: 'Request' object has no attribute 'g'

Any thoughts on how to go about this would be appreciated
Thanks
Ramone

 

[Malcolm]

Hi there,

I appreciate that you used the BBCode, but just a suggestion... When you are posting long bits if code its best to use the </>.

This is a little out of my league, however, I'll see who might be able to answer this!

@Krusty the Senile @swift @Ghost @simong1993

 

[Ramone]

Thanks Malcolm. I'll remember to enclose the code in </> in future. In the meantime, I'll keep chipping away at it and experiment with flask g or sessions in a smaller project. But I am still open to any ideas on the best way to approach this issue.

 

[Ghost]

x = "awesome"

def myfunc()
  global x
  x = "fantastic"
  print("Python is " + x)

myfunc()

print("Python is " + x)

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You need to declare a variable outside of the function scope first, as you can see above. The word 'global' is used to show that the variable being used inside the function is actually a reference to a variable not given to the function as a parameter.

For example, in almost any programming language you can search "how to use global variable in language?" or "language global variables" will almost always pull up a tutorial or example code for how to access a variable in a function, change it, etc.

 

[Ramone]

Thanks for that Ghost. I'll look in to that way of handling this..