HTTP 请求标头中的 C# 错误

Question

I want to use the service Microsoft Cognitive Service. I wrote this code :

static async void MakeRequest()
    {
        var client = new HttpClient();
        var queryString = System.Web.HttpUtility.ParseQueryString(string.Empty);

        //Request headers
        client.DefaultRequestHeaders.Add("Ocp-Apim-Subscription-Key", ".......");

        //Requests parameters
        queryString["returnFaceId"] = "true";
        queryString["returnFaceLandmarks"] = "false";
        queryString["returnFaceAttributes"] = "age,smile,gender";
        var uri = "https://api.projectoxford.ai/face/v1.0/detect?" + queryString;
        //var uri = "https://api.projectoxford.ai/face/v1.0/detect?returnFaceId=true&returnFaceLandmarks=false&returnFaceAttributes=age,smile,gender";
        HttpResponseMessage response;

        //request body
        byte[] byteData = Encoding.UTF8.GetBytes("http://ima..uniserv...248.jpg");

        using (var content = new ByteArrayContent(byteData))
        {
            content.Headers.ContentType = new MediaTypeHeaderValue("application/json");
            //
            response = await client.PostAsync(uri, content);
        }
        Console.WriteLine(response);

    }

After execution I see :

I don't understand where is my error for a header. Thank's for your help.

Answer 1

thank you for answer. I understand the problem. i replace this :

byte[] byteData = Encoding.UTF8.GetBytes("{\\"url\\":\\" http://im...8.jpg \\"}");

Now my problem is to obtain the result on this form :

[

{

"faceId": "bed2c25c-3fab-4a72-b32b-a44797b1bf1a",

"faceRectangle": {

  "top": 98,

  "left": 135,

  "width": 201,

  "height": 201

},

"faceAttributes": {

  "smile": 0.002,

  "gender": "male",

  "age": 30.6

}

}

]

thaks a lot for help!