如何從 models.py 調用 function 到視圖或模板

Question

我是 Django 和 Python 的初學者。 我正在創建一個工資單項目，其計算是使用 models.py 中的 function 完成的。 用戶必須通過模板輸入變量並保存到sql。 然后搜索員工（再次通過模板）和 output 他的工資單詳細信息。 那是我想使用計算function的時候。

來自數據庫的數據正在工作並由模板輸出。 至於計算出來的數據，根本就沒有顯示出來。

我一直在嘗試使用 function 無濟於事，我已經搜索了 3 天。 我不知道現在該做什么。

模型.py

from django.db import models 

#Class in model.py acts as a table in database
class Add_Employee(models.Model): 
    name = models.CharField (max_length = 150, default = '', null = False)
    position = models.CharField (max_length = 150, default = '', null = False)
    email = models.EmailField (max_length = 150, default = '', null = False)
    address = models.CharField (max_length = 500, default = '', null = False)
    basic_pay = models.FloatField(default=None) 
    overtime_hours = models.IntegerField(default=None)
    allowance = models.FloatField(default=None)
    days_leave = models.IntegerField(default=None)
    other_deductions = models.FloatField(default=None)


    #Django admin page; the table will show the name
    def __str__(self):
        return '{}{}'.format(self.name, self.position, self.email, self.address)

    def salary_calculation(self):

        #Earnings
        self.overtime_hours_pay = self.overtime_hours * 64 

        self.gross_income = self.basic_pay + self.overtime_hours + self.allowance

        #Deductions
        self.days_leave = self.days_leave * 512
        self.pagibig = self.basic_pay * 0.01
        self.gsis = self.basic_pay * 0.09
        self.withholdingtax = self.basic_pay * 0.15
        self.philhealth = self.basic_pay * 0.0275 / 2

        self.total_deductions = self.days_leave + self.pagibig + self.gsis + self.withholdingtax + self.philhealth

        #Net Pay
        self.net_pay = self.gross_income - self.total_deductions

        print ("Calculated.") #this was never outputted from all the times i tried.
        return (self)

視圖.py

#Code for form submission and redirect back to employer page again
def add_employee_form_submit(request):
    print ("Form is successfully submitted.") #print can only be seen on the terminal, not the browser


    #create local variable for each variable entered using the form
    name = request.POST["name"]
    address = request.POST["address"]
    email = request.POST["email"]
    position = request.POST["position"]
    basic_pay = request.POST["basic_pay"]
    overtime_hours = request.POST["overtime_hours"]
    allowance = request.POST["allowance"]
    days_leave = request.POST["days_leave"]
    other_deductions = request.POST["other_deductions"]

    #assigning the local variable into the database fields
    employee_info = Add_Employee(name = name, address = address, email = email, position = position, basic_pay = basic_pay, overtime_hours = overtime_hours, allowance = allowance, days_leave = days_leave, other_deductions = other_deductions )

    #save the entire stuff
    employee_info.save()

    return render(request, 'employer.html')


def search_employee_form_submit(request):
    if request.method == "POST":
        search_id = request.POST['search_id']
        
        if search_id:
            employee_match = Add_Employee.objects.filter( pk = search_id ) #pk is primary key
            
            if employee_match:

                return render (request, 'employee.html', {'Search': employee_match})
            else:
                messages.error(request, 'No results found.')

        else: 
            return HttpResponseRedirect('employee/')

    return render(request, 'employee.html')

employee.html（查詢和結果查看模板）

    <h1>Employee Payroll</h1>
    <br><br>
    <h2>Enter your ID:</h2>
    <form action="/search_employee_form_submit/", method="post"> <!--it will use 'search_employee_form_submit' url after submitting form-->

        {% csrf_token %} <!-- added for privacy reasons/security-->
        <br>
        <input type = "text" name="search_id" placeholder="Enter employee id">
        <br><br>
        <input type="submit" value="search employee">
    </form>
    <br><br>

    <!-- Code for when your search has results / employee -->
    {% if Search %}
        {% for k in Search %}
            Name: 
            {{ k.name }} <br>
            Position:
            {{ k.position }} <br>
            Email: 
            {{ k.email }} <br>
          ..... etc (this part is working)

            Overtime Hour Pay:
            {{ k.overtime_hours_pay }}<br>
            Gross Income:
            {{ k.gross_income }}<br><br> 
          ..... etc (calculated data = doesnt show result)
        {% endfor %}

請原諒我的長篇文章，因為我不知道我在哪里遺漏了一些東西。

Answer 1

首先，您引用了 model 中不存在的字段，例如overtime_hours_pay和gross-income 。 如果您在 model 實例上執行self.someFieldName ，則應在 model 中定義或繼承該字段。 所以這是錯誤的：

self.overtime_hours_pay = self.overtime_hours * 64

你也可以

• 在 model 定義中添加這些字段
• 刪除self部分並使它們成為普通變量。 看起來像：

def salary_calculation(self):
        overtime_hours_pay = self.overtime_hours * 64 

        gross_income = self.basic_pay + self.overtime_hours + self.allowance

        self.days_leave = self.days_leave * 512
        pagibig = self.basic_pay * 0.01
        gsis = self.basic_pay * 0.09
        withholdingtax = self.basic_pay * 0.15
        philhealth = self.basic_pay * 0.0275 / 2

        total_deductions = self.days_leave + pagibig + gsis + withholdingtax + philhealth

        net_pay = gross_income - total_deductions

        return net_pay

之后，您可以在視圖中計算 net_pay。

...
if employee_match:
    # calculation
    net_pay = employee_match.salary_calculation()
    # then pass this to the template
    return render (request, 'employee.html', {'Search': employee_match, 'net_pay': net_pay})
else:
    messages.error(request, 'No results found.')