How to convert this C# code to vb.net

[Gobindap]

using (var client = new HttpClient())
{
client.DefaultRequestHeaders.Accept.Clear();
client.DefaultRequestHeaders.Accept.Add(new
MediaTypeWithQualityHeaderValue("application/json"));
BillViewModel p = new BillViewModel
{
username = "Test_CBMS", password = "test@321", seller_pan = "999999999",
buyer_pan = "123456789",
buyer_name="", fiscal_year = "2073.074", invoice_number="102",
invoice_date="2074.07.06", total_sales=1000.01,
taxable_sales_vat=1000.01, vat=130, excisable_amount=0, excise=0,
taxable_sales_hst=0,
hst=0, amount_for_esf=0, esf=0, export_sales=0,
tax_exempted_sales=0,isrealtime=true, datetimeclient = Datetime.now };
client.BaseAddress = new Uri("http://202.166.207.75:9050");
var response = client.PostAsJsonAsync("api/bill", p).Result; if
(response.IsSuccessStatusCode)
{
var result = response.Content.ReadAsStringAsync();
Console.Write(result.Result);
Console.ReadLine();
} else
{
Console.Write("Error");
Console.ReadLine();
}
}

=================================
It tried it as following

Using client = New HttpClient()
            client.DefaultRequestHeaders.Accept.Clear()
            client.DefaultRequestHeaders.Accept.Add(New MediaTypeWithQualityHeaderValue("application/json"))
            Dim p As BillViewModel = New BillViewModel With {
             .username = "Test_CBMS",
             .password = "test@321",
             .seller_pan = "999999999",
             .buyer_pan = "123456789",
             .buyer_name = "",
             .fiscal_year = "2073.074",
             .invoice_number = "102",
             .invoice_date = "2074.07.06",
             .total_sales = 1000.01,
             .taxable_sales_vat = 1000.01,
             .vat = 130,
             .excisable_amount = 0,
             .excise = 0,
             .taxable_sales_hst = 0,
             .hst = 0,
             .amount_for_esf = 0,
             .esf = 0,
             .export_sales = 0,
             .tax_exempted_sales = 0,
             .isrealtime = True,
             .datetimeClient = DateTime.Now
            }
            client.BaseAddress = New Uri("http://202.166.207.75:9050")
 
            'Dim response = client.PutAsync("api/bill", p).Result
 
            Dim response = client.PostAsJsonAsync("api/bill", p).Result
            If response.IsSuccessStatusCode Then
                Dim result = response.Content.ReadAsStringAsync()
                Console.Write(result.Result)
                Console.ReadLine()
            Else
                Console.Write("Error")
                Console.ReadLine()
            End If
        End Using
 

==========================
but is show error in " Dim response = client.PostAsJsonAsync("api/bill", p).Result"

it says
'PostAsJsonAsync' is not a member of 'System.Net.Http.HttpClient'.


Please please please help me.
Thank you.

[Frinavale]

According to the documentation on the MSDN Library for the PostAsJsonAsync method...it is only available if you are referencing the System.Net.Http namespace in the System.Net.Http.Formatting assembly.

Make sure you have referenced everything appropriately.