Deserialize list of objects in C#

Question

I Use JsonConvert to serialize an object and save it in a database.
This is a sample of the serialized string that I saved in database:

[{"matId":"1","value":"44"},{"matId":"2","value":"55"},{"matId":"4","value":"77"}]

Now when I get this string from database which has a lot of backslashes like this:

"[{\"matId\":\"1\",\"value\":\"44\"},{\"matId\":\"2\",\"value\":\"55\"},{\"matId\":\"4\",\"value\":\"77\"}]"

And for this reason I can't Deserialize it.

.Replace("\\","") method doesn't create any affect on this. I don't know why.

Mihai Alexandru-Ionut · Accepted Answer · 2017-04-14T18:02:01.677

11

You have to use JsonConvert.Deserialize method.

Your json string is wrapped within square brackets ([]), hence it is interpreted as array. Therefore, you need to deserialize it to type collection of one class, for example let's call it MyClass.

public class MyClass
{
    public int matId { get; set; }
    public int value { get; set; }
}

Here is Deserialize method.

var results=JsonConvert.DeserializeObject<List<MyClass>>(json);

edited Apr 14 '17 at 18:02

answered Apr 14 '17 at 17:17

Mihai Alexandru-Ionut

47,092
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3

I get an error when I Deserialize , `Cannot deserialize the current JSON array (e.g. [1,2,3]) into type 'my type' because the type requires a JSON object (e.g. {"name":"value"}) to deserialize correctly.` – user3748973 Apr 14 '17 at 17:19

score 2 · Answer 2 · answered Apr 25 '18 at 13:08

2

Backslashes represent serialized object. You need to deserialize your List object. You can try using Generics:

public List<T> Deserialize<T>(string path)
{
   return JsonConvert.DeserializeObject<List<T>>(path);
}

answered Apr 25 '18 at 13:08

Nat

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score 0 · Answer 3 · answered Oct 07 '22 at 17:59

Be careful when looking at json strings as you are debugging. In Visual Studio it needs to format the value into a string. To do that it will add " so that it can process it when actually the value does not contain them. That is why the replace does not work.

Deserialize list of objects in C#

3 Answers3

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