django changing a value of databe field using variable in view-CodePudding

Is there any way to update the by-hand value of a particular field in the model instance using variables?

For example.

models.py

class ExampleModel(models.Model):
        name=models.CharField(max_length=10)
        a=models.CharField(max_length=10)
        b=models.CharField(max_length=10)
        c=models.CharField(max_length=10)

views.py

list=[a,b,c]
fruits=[orange,apple,banana]
values
def ExampleView(request):
    model_instsnce=ExampleModel.objects.last()
    for i in list:
    instance_model.i=fruits[i]
    model_instance.save()

In my project, I tried to use something like the above but it doesn't work. 'i' from loop doesn't behave like a variable. 'i' is treated as a new field in the model.

Any idea how to use variables to designate fields from model to change?

CodePudding user response：

Since django models are essentially just objects, the model fields are just attributes. As such, you could simply use a dict to map the field-value pairs you want to update for the model and then call setattr to set them:

# store/get the model field-value pair data
fruits = {
    'a': 'orange',
    'b': 'apple',
    'c': 'banana'
}

def ExampleView(request):
    model_instance = ExampleModel.objects.last()
    # update the model fields
    for key, value in fruits.items():
        setattr(model_instance, key, value)
    model_instance.save()

I'm assuming that you're getting the update values dynamically as well so you'd have to adjust the above code for that, but overall I think this addresses the main point of your question.

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