反序列化 C# 中的对象列表

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.

Answer 1

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);

Answer 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);
}

Answer 3

MyClass result = JsonConvert.DeserializeObject<MyClass>(jsonString);

Answer 4

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.