The json value could not be converted to system.collections.generic.list

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The error message the json value could not be converted to system.collections.generic.list occurs when trying to convert a JSON value into a List object in a .NET application.

Here is an example to illustrate the issue:


string json = "[1, 2, 3, 4, 5]";
try
{
    List<int> list = JsonConvert.DeserializeObject<List<int>>(json);
}
catch (JsonSerializationException ex)
{
    Console.WriteLine(ex.Message);
}

In this example, we are trying to deserialize a JSON array into a List<int> object. However, if the JSON value is invalid or cannot be converted to the specified type, a JsonSerializationException will be thrown with the message the json value could not be converted to system.collections.generic.list.

To fix this issue, make sure that the JSON value and the target type are compatible. The JSON array should contain elements that can be mapped to the specified type. For example, if the JSON array contains string values, you cannot directly convert it to a List<int>. You would need to modify the JSON or use a different target type.


// Valid JSON array of integers
string json = "[1, 2, 3, 4, 5]";
List<int> list = JsonConvert.DeserializeObject<List<int>>(json);
foreach (int value in list)
{
    Console.WriteLine(value);
}

In this revised example, the JSON array contains integers, which can be successfully converted to a List<int> object without any exceptions.

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