在Django中删除前导零

Question

I'm displaying data from my MySQL database. I would like to remove the leading zeros in a certain fields(the ops and obp fields), only when the value to the left of the decimal point is a 0. If the digit(s) to the left of the decimal point is not 0, then I obviously want that displayed.

For instance,

• 0.750 becomes .750

• 1.000 stays as is

I suspect this can be done in when calling the data using django template or in the views.py. How would I do either one?

Any help on this would be greatly appreicated! Thank You.

views.py

from django.shortcuts import render
from .models import BattingRegStd


# Create your views here.
def batting(request):
    battingregstd2018 = BattingRegStd.objects.filter(year=2018)
    return render(request, 'playerstats/battingReg2018.html', {'battingregstd2018':battingregstd2018})

models.py

class BattingRegStd(models.Model):
    id = models.IntegerField(db_column='ID', primary_key=True)  # Field name made lowercase. 
    obp = models.FloatField(db_column='OBP', blank=True, null=True)  # Field name made lowercase.
    ops = models.FloatField(db_column='OPS', blank=True, null=True)  # Field name made lowercase.
    tb = models.IntegerField(db_column='TB', blank=True, null=True)  # Field name made lowercase.

HTML

{% extends "base.html" %} 

{% block contents %}
<div>
    <table>
        <thead>
            <tr>
                <th>OBP</th>
                <th>OPS</th>
                <th>TB</th>
            </tr>
        </thead>
        <tbody>
            {% for index in battingregstd2018%}
                <td>{{ index.obp}}</td>
                <td>{{ index.ops}}</td>
                <td>{{ index.tb}}</td>
            </tr>
            {% endfor %}
        </tbody>
    </table>
</div>
{% endblock %}

Answer 1

You can use

def batting_avg_format(num):
    numstr = str(num)
    if numstr[0]!='0':
        return numstr
    else:
        return numstr[1:]

Either incorporate it as a method on your BattingRegStd Model and apply it, or directly do a list comprehension after you have filtered the model but before your render your HTML. The advantage of incorporating it as a model method is that you can now call it from the template, as long as the only parameter in your method is self .

Answer 2

Examples you can confirm in a Python shell, tested with Python 3.5.3:

x = "0.750"
x.lstrip("0")
> '.750'

# Included because a normal floating point type won't print trailing zeroes:
from decimal import Decimal
x = Decimal("0.750")
x.to_eng_string().lstrip("0")
> '.750'
str(x).lstrip("0")
> '.750'

While you won't be able to do this in Django templates unless you've swapped out the engine for jinja2 or something else that allows parens in method calls, you can either do this in the view (possibly ugly depending on how you're pulling this data) or in a simple custom template filter .

Answer 3

I assume that value is greater than zero.

views.py

def batting(request):
    battingregstd2018 = BattingRegStd.objects.filter(year=2018)

    for i in range(0, len(battingregstd2018)):
        # if need to edit value
        if battingregstd2018[i].obp is not None and battingregstd2018[i].obp < 1:
            # data edit as string
            # data type does not matter in template
            battingregstd2018[i].obp = str(battingregstd2018[i].obp)[1:]
        if battingregstd2018[i].ops is not None and battingregstd2018[i].ops < 1:
            battingregstd2018[i].ops = str(battingregstd2018[i].ops)[1:]

    return render(request, 'playerstats/battingReg2018.html', {'battingregstd2018':battingregstd2018})

than second attempt,
let's just fix template this time. use the original view.py

{% for index in battingregstd2018%}
    <td>
    {% if index.obp is None %}
    -
    {% elif index.obp < 1 %}
    .{{index.obp|slugify|slice:"1:"}}
    {% else %}
    {{index.obp}}
    {% endif %}
    </td>
{% endfor %}

.{{index.obp|slugify|slice:"1:"}}
|slice can only be used in string data type.
|slugify converts to ASCII for use |slice . but decimal point is deleted.
so i added . to the front.

ps)
maybe, float type will store 0.750 as 0.75 . if you want to 0.750 than use it .{{index.obp|floatformat:"3"|slugify|slice:"1:"}}