Converting a JSON String from a datatable into a JObject c# - json

Question

I am looking for some help with a datatable conversion into a JObject. I am using C# in visual studio along with the Newtonsoft JSON .net library. I have retrieved my datatable from my database.
From here I took the data table and processed it through this class:
public string DataTableToJSONString(DataTable table)
{
string JSONString = string.Empty;
JSONString = JsonConvert.SerializeObject(table,Formatting.Indented);
return JSONString;
}
Now that the object has been converted to a JSONString successfully (It throws no errors at this point) via the Newtonsoft JSON.net Library, I am unable to parse it into a JObject with this code:
Note: "json" is the string variable I placed the returned value from the DatatabletoDataTableToJSONString() method into..
JObject job = JObject.Parse(json);
I continuously get the following error...
Error reading JObject from JsonReader. Current JsonReader item is not an object: StartArray. Path '', line 1, position 1.
The reason I need it in the form of a JObject it to pass it into the following post method for an API:
public static async Task<JObject> Post(string url, JObject data)
{
// Create an HttpClient instance
HttpClient client = new HttpClient();
client.DefaultRequestHeaders.Authorization = CreateBasicHeader(ClientContext.Username, ClientContext.Password);
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
// Send a request asynchronously and continue when complete
var requestbody = new StringContent(data.ToString(), Encoding.UTF8, "application/json");
HttpResponseMessage response = await client.PostAsync(url, requestbody);
dynamic content = await response.Content.ReadAsAsync<JObject>();
// Check that response was successful or throw exception
try
{
response.EnsureSuccessStatusCode();
}
catch (Exception ex)
{
throw new Exception("Status Code: " + response.StatusCode + "\r\nMessage: " + content[0].ToString(), ex);
}
// Read response asynchronously as a JObject
return content;
}
I would appreciate any help on this as I have been researching for 2 weeks with no luck. This one is really killing me. Thanks in advance to all who take the time to examine this.
UPDATE: I ended up adding in the following bit of code as I realized I was returning an array when I pulled the data table.
string jsonresult = JsonConvert.SerializeObject(dt);
JArray aray = JArray.Parse(jsonresult);
//I then have code for the API login credentials here....
foreach (JObject item in aray)
{
ApiClient.Post(Url, item).Wait();
}
This appears to pass in the JObjects just fine into the post method although I get the following error:"AggregateException was unhandled..." I set a break point and the flaw appears to happen at the:
try
{
response.EnsureSuccessStatusCode();
}
After attempting the response.ensuresuccessstatusCode(); The program of course jumps to the catch....
catch (Exception ex)
{
throw new Exception("Status Code: " + response.StatusCode + "\r\nMessage: " + content.message.ToString(), ex);
}
Again, any help would be appreciated. I am almost there with this. After it posts, I will be done.... Thanks again in advance to everyone. I apologize for being long winded.

Answer 1

Your problem is that JSON has two types of containers: arrays and objects:
An object is an unordered set of name/value pairs. An object begins with { (left brace) and ends with } (right brace).
The corresponding LINQ to JSON class is JObject.
An array is an ordered collection of values. An array begins with [ (left bracket) and ends with ] (right bracket). Values are separated by , (comma).
The corresponding LINQ to JSON class is JArray.
So, how does Json.NET serialize a data table? From the documentation Serialize a DataSet, we can see that each table is serialized as an array.
If you attempt to parse a JSON string whose root object is an array into a JObject, you will get this exception.
Instead, you must return a JArray, or better yet a JToken which is the root class for all JSON entities:
public static async Task<JToken> Post(string url, JObject data)
{
// Create an HttpClient instance
HttpClient client = new HttpClient();
client.DefaultRequestHeaders.Authorization = CreateBasicHeader(ClientContext.Username, ClientContext.Password);
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
// Send a request asynchronously and continue when complete
var requestbody = new StringContent(data.ToString(), Encoding.UTF8, "application/json");
HttpResponseMessage response = await client.PostAsync(url, requestbody);
dynamic content = await response.Content.ReadAsAsync<JToken>();
// Check that response was successful or throw exception
try
{
response.EnsureSuccessStatusCode();
}
catch (Exception ex)
{
throw new Exception("Status Code: " + response.StatusCode + "\r\nMessage: " + content[0].ToString(), ex);
}
// Read response asynchronously as a JToken
return content;
}

Answer 2

I am answering this thread and closing it as the original question has technically been answered. I simply converted the JArray into its respective JObjects with the following bit of code.
foreach (JObject item in aray)
{
ApiClient.Post(Url, item).Wait();
}
Although I am still working on debugging, I was technically able to pull the Object out of the array that I got from the data table.
Thanks all!!!!!