Unable to map JSON to class

Question

I make a request to an external API and get JSON data back, the data returned is in the following format:

abnCallback({
    "Abn": "53660112345",
    "AbnStatus": "Active",
    "AbnStatusEffectiveFrom": "2022-06-16",
    "Acn": "660198745",
    "AddressDate": "2022-06-16",
    "AddressPostcode": "3000",
    "AddressState": "VIC",
    "BusinessName": [],
    "EntityName": "Company name pty ltd",
    "EntityTypeCode": "PRV",
    "EntityTypeName": "Private Company",
    "Gst": "2022-06-16",
    "Message": ""
})

I'm trying to map this to a model by doing the following:

var jsonString = await response.Content.ReadAsStringAsync();
var response = JsonConvert.DeserializeObject<ABRPayloadSearchResults>(jsonString);

My model looks like this:

public class ABRPayloadSearchResults
{
    public string Abn { get; set; }
    public string AbnStatus { get; set; }
    public string AbnStatusEffectiveFrom { get; set; }
    public string Acn { get; set; }
    public string AddressDate { get; set; }
    public string AddressPostcode { get; set; }
    public string AddressState { get; set; }
    public object[] BusinessName { get; set; }
    public string EntityName { get; set; }
    public string EntityTypeCode { get; set; }
    public string EntityTypeName { get; set; }
    public string Gst { get; set; }
    public string Message { get; set; }
}

The issue I have is the returned JSON has abnCallBack( at the start which is preventing the json being mapped correctly to my class, has anyone had to handle this situation before?

score 1 · Accepted Answer · answered Aug 11 '22 at 06:19

This format is called JSONP. It wraps a JSON object in a (javascript) function call, which enables a browser to download the JSON via a <script>. This can be used to circumvent cross origin policies to load JSON from other domains.

I don't believe there is a built-in way to deserialize JSONP in C#, but you should be able to manipulate the string quite easily to remove the function name and the brackets. See e.g. How to deserialize a JSONP response (preferably with JsonTextReader and not a string)?

Phillip Ngan · Answer 2 · 2022-08-11T06:28:24.683

Get the index of the open curly bracket and the number of chars to the closing curly bracket. Enter those parameters into a substring operation. This will return the contents between the brackets and the brackets. You need to add handling for real world cases, such as extra curly brackets, and empty string, but the code example gives the general idea.

var input = @"abnCallback({
""Abn"": ""53660112345"",
""AbnStatus"": ""Active"",
""AbnStatusEffectiveFrom"": ""2022-06-16"",
""Acn"": ""660198745"",
""AddressDate"": ""2022-06-16"",
""AddressPostcode"": ""3000"",
""AddressState"": ""VIC"",
""BusinessName"": [],
""EntityName"": ""Company name pty ltd,
""EntityTypeCode"": ""PRV"",
""EntityTypeName"": ""Private Company"",
""Gst"": ""2022-06-16"",
""Message"": """"})";

int from = input.IndexOf("{");
int to = input.IndexOf("}");

var jsonString = input.Substring(from, to - from + 1);

This only works with a single JSON object without child objects. Be aware when using this solution when using a different JSON model. — klekmek, Aug 11 '22 at 07:06

Unable to map JSON to class

2 Answers2