How to set the part of request params nil ?

[maxlcoder]

for example :
post params

{
  "id": 1,
  "products": null
}

then be able to judge req.Procuts is nil , not empty array

[kesonan]

Why you need nil array? by default, if you missing the array value, in request, the length must be 0.

[maxlcoder]

Why you need nil array? by default, if you missing the array value, in request, the length must be 0.

I want to determine if the user has filled out a field ,whether they have left it blank or not? Such as :

1. nil means user not edit the field
2. empty means user left it blank , then here will set the data to empty from other content