Retrieving From A WEBAPI Into a textview in xamarin

Question

_meta:{totalCount:17pageCount:1currentPage:1perPage:20}} im new to programming and i need help in retrieving the results from the webapi to my textview on xamarin?? this is the WEBAPI address : http://api.iolab.net/v1/exams?access-token= need help.

Bhuvanesh Mohankumar · Answer

Hi Chioma Please modify the response to the proper Json format. Sample Json: [{Name:ChiomaID:1234}] Now your response has some unwanted code  or you can use the below regular expression to get valid Json var validJsonData = data.replace(/[^a-z0-9\s{}:[]]/gi '' ).replace(/[_\s]/g ' ' ); once you clean up your JSON content check the content is proper by pasting to online parser link provided. http://json.parser.online.fr/ Now you can parse the Valid Jsonand get assigned to object you require and manipulate in Xamarin. Accept as answer if helpful.

Bhuvanesh Mohankumar · Answer

Can you returnas JSON from the WEB API and try to read the JSON data in your Xamarin.

Chioma Joshua · Answer

Thank You Bhuvanesh.... Nice To Meet You....

Bhuvanesh Mohankumar · Answer

You can also check for the HTTPCollectionKeysas I searched this is due to some settings issue the error mayoccurred. Chioma Will try to post if I get any update on this.

Chioma Joshua · Answer

Thank You Bhuvanesh.. Its a mobile application..

Bhuvanesh Mohankumar · Answer

Can you add this line in your configuration file [Web.config] key = aspnet:MaxHttpCollectionKeys value = 2001 />

Chioma Joshua · Answer

hey bhuvanesh did as you suggested but its still returning the same error: System.InvalidOperationException: Operation is not valid due to the current state of the object. plus the result of the webapi is in an array...

Bhuvanesh Mohankumar · Answer

Thanks Chioma I believe this is due to the object may not available or disposed before you access that. Ican see you used -> using (WebResponse response = await request.GetResponseAsync()).... When the using is used the object will be disposed automatically may be due to which current object is out of scope. Can you try removing the using and check once that works then we can optimize the code by using keyword.

Chioma Joshua · Answer

Hello Bhuvanesh thanks for the assistance so far... i really do appreciate.. Still have a problem... i'll paste my code.. please help me.. tried debugging but its not coming through... its returning this error: System.InvalidOperationException: Operation is not valid due to the current state of the object. Code Used..: button.Click += async (sender e) => { string url = http://api.iolab.net/v1/exams?access-token; // Fetch the weather information asynchronously parse the results // then update the screen: JsonValue json = await FetchExamAsync(url); ParseAndDisplay(json); }; } private async Task FetchExamAsync(string url) { // Create an HTTP web request using the URL: HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(new Uri(url)); request.ContentType = application/json; request.Method = GET; // Send the request to the server and wait for the response: using (WebResponse response = await request.GetResponseAsync()) { // Get a stream representation of the HTTP web response: using (Stream stream = response.GetResponseStream()) { // Use this stream to build a JSON document object: JsonValue jsonDoc = await Task.Run(() => JsonObject.Load(stream)); Console.Out.WriteLine(Response: {0} jsonDoc.ToString()); // Return the JSON document: return jsonDoc; } } } private void ParseAndDisplay(JsonValue json) { TextView itemtext = FindViewById (Resource.Id.textView1); JsonValue weatherResults = json[items]; itemtext.Text = weatherResults[shortname]; }

Chioma Joshua · Answer

Bhuvanesh i dont know how to.. please help me..