Check if a key exists in request.files

I would like to iterate over request.files content and check if a key exists , however the key value is : "item_i" , so the key could be one or more : "item_0" , "item_1" "item_2" ... i would like to create a loop and retrive the keys if the keys startwith item_ save them in a list and at the end return the list lenght if it'szero returns an erro no key "item_"

code looks like :

result = []
            for (int i = 0; i < request.files.count; i++):
                key = Request.Files.GetKey(i)
                if key.startswith("item_"):
                    result.append(key)

            if len(result) == 0:
                return f" No {item_}key exists !", HTTPStatus.BAD_REQUEST,

PS : i'm using flask , not sure that request.files.count works but the most important is to iterate over all the request.files items many thanks .

Solution

If you stop your route code in the debugger and evaluate type(request.files) you'll see it's a werkzeug.datastructures.ImmutableMultiDict.

If you want to check if a key is in request.files you can just do:

if "item_0" in request.files:
    #do something

If you want to get all the keys from request.files you can use request.files.keys() and to get the number of items in request.files you can use len(request.files).

To replicate the code in your question you can use this:

result = list()
for key in request.files.keys():
    if key.startswith("item_"):
    result.append(key)