C# post json example to .vb

我试图转换一个c#的例子，发布到一个API到。vb。我的编程技能有限，所以我似乎不能让它工作。一个问题是，我不能使用httpclient，因为项目是在框架3.5，这是我不能改变。有人知道吗?

公共类TriggerData

{
    //if true, the contact will be updated with sent property data (affects performance).
    public bool saveProps { get; set; } 
    public string originalId { get; set; }
    public Dictionary<string, string> properties { get; set; } 
    public TriggerData()
    {
        properties = new Dictionary<string, string>();
    }
}
public class CarmaTriggerClient
{
    static void Main(string[] args)
    {
        //use your settings here
        var host = "https://www.adress.com";
        var customerId = 0;
        var triggerId = 0;
        var user = "";
        var pass = "";
        var data = new TriggerData();
        //unique identifier in the list
        data.originalId = "th@post.se";
        ///property keys are emailAddress, mobileNumber, firstName, lastName, city, zip, country, middleName, title, dateOfBirth, sex, or the id of one of your custom properties
        data.properties["emailAddress"] = "th@post.se";
        data.properties["4321"] = "some data";
        //REST resource for trigger
        var path = string.Format("/rest/{0}/triggers/{1}/messages", customerId, triggerId);
        TriggerAsync(host, path, user, pass, data).Wait();
    }
    static async Task TriggerAsync(string host, string path, string user, string pass, TriggerData data)
    {
        using (var client = new HttpClient())
        {
            client.BaseAddress = new Uri(host);
            client.DefaultRequestHeaders.Accept.Clear();
            client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
            var credentials = string.Format("{0}:{1}", user, pass);
            //http://www.ietf.org/rfc/rfc2617.txt
            var authorization = Convert.ToBase64String(System.Text.Encoding.Default.GetBytes(credentials));
            client.DefaultRequestHeaders.Add("Authorization", "Basic " + authorization);
            // HTTP POST
            var response = await client.PostAsJsonAsync(path, data);
            if (!response.IsSuccessStatusCode)
            {
                System.Diagnostics.Debug.WriteLine(response.Content);
            }
        }
    }
}

}