Request.form 找不到我的字段，即使它们似乎存在

Question

I am trying to submit a form with Flask using dynamic field names for multiple check boxes within a form. The naming of the fields seems to work and they have the names I want, but when I try to use request.form.get() to get the information from the form using the dynamic field names it is just returning None, meaning that the dictionary that is returned does not contain the names of my fields. Here is my code:

The Form And Example of name

HTML

<form action="{{url_for('main.updatealleles', id=fish.id)}}" method="post">
    <div id="updateAllelesBlock">
        <table id="alleleTable" style="margin: auto; margin-top:20px;">
            <tr>
                <th>Name</th>
                <th>Unidentified</th>
                <th>Identified</th>
                <th>Heterozygous</th>
                <th>Homozygous</th>
                <th>Hemizygous</th>
            </tr>
            {%for allele in alleles%}
                <tr>
                    <th>{{allele.name}}</th>
                    <td><input type="checkbox" name = {{allele.name.replace(" ", "")+"Unidentified"}}</td>
                    <td><input type="checkbox" name = {{allele.name.replace(" ", "")+"Identified"}}</td>
                    <td><input type="checkbox" name = {{allele.name.replace(" ", "")+"Heterozygous"}}</td>
                    <td><input type="checkbox" name = {{allele.name.replace(" ", "")+"Homozygous"}}</td>
                    <td><input type="checkbox" name = {{allele.name.replace(" ", "")+"Hemizygous"}}</td>
                </tr>
            {%endfor%}
        </table>
    </div>
    <button type="submit" class="btn btn-secondary" style="margin-top: 10px;">Update</button>
</form>

PYTHON

@bp.route("/fish/<id>/updatealleles/", methods=["GET", "POST"])
@login_required
def updatealleles(id):
    fish = Fish.query.filter_by(id=id).first_or_404()
    alleles = Allele.query.filter_by(fish=fish).all()

    if request.method == "POST":
        for allele in alleles:
            print(request.form.get(f"{allele.name.replace(' ', '')}Unidentfied"), file=sys.stderr)
            print(request.form.get(f"{allele.name.replace(' ', '')}Identfied"), file=sys.stderr)
            #THIS IS ALWAYS PRINTING NONE, SAME WITH ALL OTHER FIELDS

            #therefore these, and the other fields are being set to None rather than true/false
            allele.unidentified = request.form.get(f"{allele.name.replace(' ', '')}Unidentified")
            allele.identified = request.form.get(f"{allele.name.replace(' ', '')}Identified")

        db.session.commit()

            return redirect(url_for("main.updatealleles", id=fish.id))
    
        

    return render_template('updatealleles.html', fish=fish, alleles = alleles, title = "Update Alleles")

The reason I need the dynamic name fields is because there could be any number of different allele objects (they are SQLAlchemy objects) and the table is there to set different attributes for each allele object to true or false, shown in the python example. If there is a completely different way to do this that I am no aware of then I am also happy to try that.

I know there have been some similar questions to this, but I have tried all of their suggestions and none of them have worked for me, so any help would be greatly appreciated and let me know if you need any more information.

Answer 1

Okay I have the solution. It turns out even though the names appeared to be working when inspected, the jinja2 string was actually returned as unclosed when the form was requested extra information was included in the name. All I had to do to fix that was to add single quotation marks, either side of the id, so now it looks like this, for example:

 <td><input type="checkbox" name = '{{allele.name.replace(" ", "")+"Unidentified"}}'</td>

and then the python can work like this:

allele.unidentified= request.form.get(f"{allele.name.replace(' ', '')}Unidentified") == "on"

And the same for each other field.