Get id of last Rest API POST using Entity Framework - entity-framework

Question

I need to be able to access the id of a new Post. I will be using this id to populate another field called LocationId like this: "L" + id = LocationId (example L22) where 22 is the id of the new Post. Here is the code for my Post request:
private async void BtnSubmit_Clicked(object sender, EventArgs e)
{
var imageArray = FilesHelper.ReadFully(file.GetStream());
file.Dispose();
var location = new Models.Location()
{
LocationName = EntName.Text,
ImageArray = imageArray,
};
ApiServices apiServices = new ApiServices();
bool response = await apiServices.PostLocation(location);
bool response2 = await apiServices.InputLocationId(id, location);
if (!response || !response2)
{
await DisplayAlert("Alert", "Something wrong", "Cancel");
}
else
{
await DisplayAlert("Hi", "Your record has beed added successfully", "Alright");
}
await Navigation.PushAsync(new SetupPage());
This is on the client side. I have all the APIs created (such as PostLocation and InputLocationId)on Azure SQL Server. This is for a mobile inventory app built using Xamarin.
public async Task<bool> PostLocation(Location location)
{
var json = JsonConvert.SerializeObject(location);
var httpClient = new HttpClient();
var content = new StringContent(json, Encoding.UTF8, "application/json");
httpClient.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("bearer", Settings.AccessToken);
var wimsApiUrl = "http://xxxxxxx.azurewebsites.net/api/Locations";
//Get the Body of the Post
var body = await httpClient.PostAsync(wimsApiUrl, content);
//Convert it to a string
var jString = await body.Content.ReadAsStringAsync();
//Place it in a JSON Object
JObject joResponse = JObject.Parse(jString);
//Parse the JSON Object into an Int from a String
var id = int.Parse(joResponse["Id"].ToString());
//This is used in my other script to Put the LocationId of Lxx
AddNewLocationPage.NewLocationId = id;
return body.IsSuccessStatusCode;
}
My Post Location API:
// POST: api/Locations
[ResponseType(typeof(Location))]
public IHttpActionResult PostLocation([FromBody] Location location)
{
string userId = User.Identity.GetUserId();
if (!ModelState.IsValid)
{
return BadRequest(ModelState);
}
var stream = new MemoryStream(location.ImageArray);
var guid = Guid.NewGuid().ToString();
var file = String.Format("{0}.jpg", guid);
var folder = "~/Content/Images";
var fullPath = String.Format("{0}/{1}", folder, file);
var response = FilesHelper.UploadPhoto(stream, folder, file);
if (response)
{
location.ImagePath = fullPath;
}
var newLocation = new Location()
{
LocationName = location.LocationName,
User = userId,
ImagePath = location.ImagePath
};
db.Locations.Add(newLocation);
db.SaveChanges();
return Ok(new { newLocation.Id});
}
I will then take the id and put it in this Put Request to create the LocationId:
public async Task<bool> InputLocationId(int id, Location location)
{
var json = JsonConvert.SerializeObject(location);
var httpClient = new HttpClient();
var content = new StringContent(json, Encoding.UTF8, "application/json");
httpClient.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("bearer", Settings.AccessToken);
var wimsApiUrl = "http://xxxxxxx.azurewebsites.net/api/Locations/InputLocationId/";
var completeUrl = String.Format("{0}{1}", wimsApiUrl, id);
var response = await httpClient.PutAsync(completeUrl, content);
return response.IsSuccessStatusCode;
}
The InputLocationId API will automatically create the LocationId. Here is my API:
// PUT: api/Locations/5
[HttpPut]
[ResponseType(typeof(void))]
[Route("api/Locations/InputLocationId/{id}")]
public IHttpActionResult InputLocationId(int id, [FromBody] Location location)
{
//string userId = User.Identity.GetUserId();
if (!ModelState.IsValid)
{
return BadRequest(ModelState);
}
var result = db.Locations.FirstOrDefault(locationId => locationId.Id == id);
var resultant = String.Format("L{0}", id);
location.LocationName = location.LocationName;
result.LocationId = resultant;
db.SaveChanges();
return Ok("The record has been updated");
}
I am simply stuck on how to access that id!

Answer 1

// get the response body
var body = await httpClient.PostAsync(wimsApiUrl, content);
// load it into a JSON object using Newtonsoft
JObject data = JObject.Parse(body);
// get the id
var id = int.Parse(data["id"]);

Answer 2

The returns need to be converted into a string from the HttpResponseMessage.
var body = await httpClient.PostAsync(wimsApiUrl, content);
var jString = await body.Content.ReadAsStringAsync();
Then we can place it into a JSON Object:
JObject joResponse = JObject.Parse(jString);
Now this JSON Object can be parsed into an Int. Note it needs to be converted to a string.
var id = int.Parse(joResponse["Id"].ToString());