Implementation of Variable Operation in Django Template

Under the template in django, we know that variables are rendered {{xxx}}, but what happens when two variables are operated?

# Addition: 
{{value|add:value2}}
# The result returned is value+value2 The value of, assuming that you value For 40 , value2 For 60  The expression 
# The result returned is 100

# Subtraction 
{{value|add -value2}}
# And the properties of addition 1 Sample, just put the first 2 Parameters become negative, and the result returned is value-value2
# Suppose value=4,value2=8, The result returned is -4

# Multiplication 
{% widthratio value1 value2 value3%}
# The above code indicates that  value1/value2*value3,widthratio Need 3 Parameters for multiplication   Simply put the 2 Parameters equal to 1 You can 
# Example:  value1=10 value2=1 value3=2  The result returned is 10/1*2=20

# Division 
{% widthratio value1 value2 value3%}
# The result returned is   ( value1/value2 ) *value3   Simply set the value3 Equal to 1 You can divide 
# Example:  value1=100 value2=20 value3=1   The result returned is   ( 100/20 ) *1=5

Retain two decimal places for data

  <td>{{ foo.product_amount |floatformat:5 }}</td>
  register = template.Library()

1 more complicated 1 more complicated operations

With add, filter, you can do even crazier things:

Calculate A ^ 2: {% widthratio A 1 A%} Calculate (A+B) ^ 2: {% widthratio Aadd: B 1 Aadd: B%} Calculation (A+B) * (C+D): {% widthratio Aadd: B 1 Cadd: D%}

Divide and preserve decimals

First define the method in the templatehelper. py file

@register.filter
def div(value, div):
    '''
     Decimals are converted into elements, keeping two decimal places 
    :param value:
    :param div:
    :return:
    '''
    return round((value / div), 2)

It can then be used in the template as follows, provided, of course, that {% load templatehelper%}:

<td>{{ foo.product_amount |div:100 }}</td>

Try a stupid method, but it doesn't work, and even if it works, it will ignore the value after the decimal point, so it is not recommended:

<td>{% widthratio foo.product_amount 100 1 as width %}{% blocktrans %}{{ width }}{% endblocktrans %}</td>#}