问Microsoft认知服务识别文本api

EN

var client = new HttpClient();

var queryString = HttpUtility.ParseQueryString(string.Empty);

client.DefaultRequestHeaders.Add("Ocp-Apim-Subscription-Key", "{Subscription_Key_here}");

queryString["mode"] = "Printed";

var uri = "https://{region}.api.cognitive.microsoft.com/vision/v2.0/recognizeText?" + queryString;

HttpResponseMessage response;

var imagePath = @"D:\xxx\xxx\xxx\testcontent.PNG";

Stream imageStream = File.OpenRead(imagePath);

BinaryReader binaryReader = new BinaryReader(imageStream);

byte[] byteData = binaryReader.ReadBytes((int)imageStream.Length);

using (var content = new ByteArrayContent(byteData))
{
    content.Headers.ContentType = new MediaTypeHeaderValue("application/octet-stream");
    response = await client.PostAsync(uri, content);

    if (response.IsSuccessStatusCode)
    {
        var contentString = await response.Content.ReadAsStringAsync();

        var operation_location = response.Headers.GetValues("Operation-Location").FirstOrDefault();

        Console.WriteLine($"Response content is empty({contentString == string.Empty}).\n\rYou should further query the operation status using the URL ({operation_location}) specified in response header.");
    }
}