I can't JSON to List ;_; [Answered] The JSON value could not be converted to System.Collections.Generic.List1[Card]. Path: $ | LineNumber: 0 | BytePositionInLine: 1.' That's my error Here's my attempt to just call and dump it into a List. private static async Task ProcessRepositories() { var stringTask = client.GetStringAsync("https://api.magicthegathering.io/v1/cards/"); var msg = await stringTask; var cards = JsonSerializer.Deserialize<List<Card>>(msg); }

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Root Question Message

LaPetiteMortDeSam9/20/2022

I can't JSON to List ;_; [Answered]

The JSON value could not be converted to System.Collections.Generic.List`1[Card]. Path: $ | LineNumber: 0 | BytePositionInLine: 1.'

That's my error

Here's my attempt to just call and dump it into a List.

        private static async Task ProcessRepositories()
        {
            var stringTask = client.GetStringAsync("https://api.magicthegathering.io/v1/cards/");
            var msg = await stringTask;
            var cards = JsonSerializer.Deserialize<List<Card>>(msg);
        }

LaPetiteMortDeSam9/21/2022

I looked at the JSON returned and it starts like this {"cards":[{"name":"Ancestor's** so I see where my issue is, but I don't know how to address it.

LaPetiteMortDeSam9/21/2022

a <List<Card> is not the same as a {"cards": arrayOfCards

LaPetiteMortDeSam9/21/2022

so I understand I should make a class for the "cards" in the json, with my existing Cards class inside of it. I'm going to try that.

mtreit9/21/2022

Did you create the json by hand?

LaPetiteMortDeSam9/21/2022

No it's return from the URL above

LaPetiteMortDeSam9/21/2022

https://api.magicthegathering.io/v1/cards/
This returns 100 cards as default

LaPetiteMortDeSam9/21/2022

and the opening {"cards":[{"name":"Ancestor's here indicates there is an object above the actual card when returning multiple correct? I don't know what it looks like when returning 1 card alone

LaPetiteMortDeSam9/21/2022

that was meant to be a question. sorry

mtreit9/21/2022

Are you using Visual Studio?

LaPetiteMortDeSam9/21/2022

yepper

mtreit9/21/2022

This might help you:

LaPetiteMortDeSam9/21/2022

what do i click on?

mtreit9/21/2022

That's on the Edit menu

LaPetiteMortDeSam9/21/2022

lol I'm misunderstanding.

mtreit9/21/2022

LaPetiteMortDeSam9/21/2022

yeah I just gotta copy the return first.

LaPetiteMortDeSam9/21/2022

still get the error using autogenerated content

LaPetiteMortDeSam9/21/2022

sec

mtreit9/21/2022

Did you try deserializing to RootObject?

LaPetiteMortDeSam9/21/2022

System.Text.Json.JsonException: 'The JSON value could not be converted to System.Collections.Generic.List`1[Rootobject]. Path: $ | LineNumber: 0 | BytePositionInLine: 1.'

mtreit9/21/2022

No, just RootObject

mtreit9/21/2022

Not List

LaPetiteMortDeSam9/21/2022

oh lmao

LaPetiteMortDeSam9/21/2022

okay

LaPetiteMortDeSam9/21/2022

okay that worked. I understand a bit now.

LaPetiteMortDeSam9/21/2022

I wasn't adding Card as array in my previous class

LaPetiteMortDeSam9/21/2022

second question, if it returns one object, this form is still generally valid, or is it implementation dependent

mtreit9/21/2022

Not sure what you mean

LaPetiteMortDeSam9/21/2022

the fact that the return structure is a list of cards in this case

mtreit9/21/2022

Totally depends on what was serialized

LaPetiteMortDeSam9/21/2022

if it's one card returned it'd probably still be {"cards": oneCardInArray

LaPetiteMortDeSam9/21/2022

oh alright

mtreit9/21/2022

BTW you can change Card[] to List<Card> and it should still work just fine.

LaPetiteMortDeSam9/21/2022

yeah thanks for that too

LaPetiteMortDeSam9/21/2022

so when the json has an array built in I can't use the Deserialize<List<Object>

LaPetiteMortDeSam9/21/2022

that is what was tripping me up because EVERY tutorial on it I found was using that the deserialize multiple objects returned b ythe json

mtreit9/21/2022

I don't actually work with JSON that much but I don't think you can choose to deserialize a subset of the data. I think other formats like protobuf actually support that but I'm not aware that JSON does.

LaPetiteMortDeSam9/21/2022

well not to to a portion, just the way you tell it it's a list

LaPetiteMortDeSam9/21/2022

or array

LaPetiteMortDeSam9/21/2022

but either way I understand a bit more, and thank you very much for that.

mtreit9/21/2022

You can serialize a List<Card> yourself to see what that looks like in JSON. The root element is a JSON array in that case.

mtreit9/21/2022

It looks like this (I removed all properties except Name for brevity)

[{"Name":"Card 0"},{"Name":"Card 1"},{"Name":"Card 2"},{"Name":"Card 3"},{"Name":"Card 4"},{"Name":"Card 5"},{"Name":"Card 6"},{"Name":"Card 7"},{"Name":"Card 8"},{"Name":"Card 9"}]

LaPetiteMortDeSam9/21/2022

Yeah I get that bud

mtreit9/21/2022

Now you could take that and deserialize that to a List<Card>. But that's not the format that the web site is giving you.

LaPetiteMortDeSam9/21/2022

so what's the point of deserialize<list<object>>

LaPetiteMortDeSam9/21/2022

right that's not the format

LaPetiteMortDeSam9/21/2022

yeah I was just approaching it the wrong way because I didn't look at the data

mtreit9/21/2022

The point is that you would use that for data that is formatted like the example I gave above.

LaPetiteMortDeSam9/21/2022

Yeah that's how the bulk data is formatted

LaPetiteMortDeSam9/21/2022

I tried that first which is why I was on this path lol

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