HttpClient中的c＃http内容

Question

I am trying to send a json to a certain localhost site but somehow im not able to do it properly. Im getting an issue in the PostAsync line:

Cannot implicitly convert type 'System.Threading.Tasks.Task<System.Net.Http.HttpResponseMessage>' to 'System.Net.Http.HttpResponseMessage

I do not really know how to fix the conversion, thanks for any help.

using (HttpClient client = new HttpClient())
{
    try
    {
        StringContent json = new StringContent(jsonText, Encoding.UTF8, "application/json");
        HttpResponseMessage response = client.PostAsync("http://www.localhost.com/", json);
        response.EnsureSuccessStatusCode();
        string responseBody =  response.Content.ReadAsStringAsync();
        // Above three lines can be replaced with new helper method below
        // string responseBody = await client.GetStringAsync(uri);

        Console.WriteLine(responseBody);
    }
    catch (HttpRequestException e)
    {
        Console.WriteLine("\nException Caught!");
        Console.WriteLine("Message :{0} ", e.Message);
    }
}

Answer 1

请尝试添加等待您的PostAsync和ReadAsStringAsync最好的问候。

Answer 2

When executing asynchronous function calls you have to await task completion before getting actual return value of function.

Also please notice that when your method has at least one await you have to decorate your method with async keyword.

Following is working example of your code snippet.

using (HttpClient client = new HttpClient())
{
    try
    {
        StringContent json = new StringContent(jsonText, Encoding.UTF8, "application/json");
        HttpResponseMessage response = await client.PostAsync("http://www.localhost.com/", json);
        response.EnsureSuccessStatusCode();
        string responseBody = await response.Content.ReadAsStringAsync();
        // Above three lines can be replaced with new helper method below
        // string responseBody = await client.GetStringAsync(uri);

        Console.WriteLine(responseBody);
    }
    catch (HttpRequestException e)
    {
        Console.WriteLine("\nException Caught!");
        Console.WriteLine("Message :{0} ", e.Message);
    }
}

There are plenty of good Q&A's regarding async/await issue, one good example here .