HttpClient.PostAsync terminates program with exit code 0

Question

Have look around the web and not found any answers.. I did find a post here with my same problem but it does not resolve my issue. (HttpClient.PostAsync knocks out the app with exit code 0)

When I run this code, the post to vendorAddress works. but when I get to post PaymentTerms the program terminates on the postAsync function with no error message, code or anything. I don't understand why it works for one but not the other..

I have taken the same Url and json text and done a post thru chrome using the postman plugin. Both calls work and I can get results back.

I have changed my post to use WebClient and both call work and I get results. but I need to keep HTTPClient service in my code.

Any suggestions?

static void Main(string[] args)
    {
       RunAsync().Wait();
    }

    static async Task RunAsync()
    {

        try
        {
            // works
            var result = await enconPostData("vendorAddress", JsonVendorAdd);

            // does not work.  fails on postAsync
            var result1 = enconPostData("PaymentTerms", null);
        }
        catch (Exception e)
        {
            Console.WriteLine(e.Message);
        }           
    }

    static public async Task<string> enconPostData(string datatype, Object[] jsObject)
    {
        ////jsObject is a json string/object////

        string jsonString = null, URIaddress = null;

        switch (datatype)
        {                
            case "vendorAddress":
                // Create Json Object to post
                //EnVendors enconvend = new EnVendors();
                EnVendors envend = new EnVendors();

                envend.data = (Vendor[])jsObject;

                URIaddress = baseUrl + "api/CONTACTS/UpdateXXXXXX";

                // Serialize to a JsonString
                jsonString = JsonConvert.SerializeObject(enconvend);                 
                break;

            case "PaymentTerms":                   
                ContractInput entermdate = new ContractInput();
                //Set JsonObject here with dates
                entermdate.DateFrom = new DateTime(2016, 10, 1);
                entermdate.DateTo = new DateTime(2016, 10, 30);


                URIaddress = baseUrl + "api/PaymentTerms/ActiveXXXXXX";

                // Serialize to a JsonString
                jsonString = JsonConvert.SerializeObject(entermdate);

                break;
        }

        return await PostAsync(URIaddress, jsonString);
    }

    static public async Task<string> PostAsync(string uri, string jsonString)
    {

        // Post to API Call
        using (var Client = new HttpClient())
        {                   
        /////////
        /// program aborts here at PostAsync on PaymentTerms Call.   works fine for vendorAddress
       ////////
            var response = await Client.PostAsync(uri, new StringContent(jsonString, Encoding.UTF8, "application/json"));
            //will throw an exception if not successful
            response.EnsureSuccessStatusCode();

            string content = await response.Content.ReadAsStringAsync();
            return await Task.Run(() => content);

        }
    }

Answer 1

Well, I have figured out my issue on reviewing my post here. I had a break point set, so the red color of the break point made it hard to see my problem.

on line 22 of my example var result1 = enconPostData("PaymentTerms", null);

is missing the await command var result1 = await enconPostData("PaymentTerms", null);

once I added that.. I get my results, and the program did not terminate.

synchronous call vs asynchronous call

Thanks all.. just needed a new perspective i guess.