POST-Request in Xamarin WebView? - post

Question

I've a simple Xamarin.Forms page with a WebView in it, working well.
Now I want to call POST-Requests (sending form-data) for an URL.
Do I have to create 3 different views for Android, iOS and UWP to achieve that - or is there a way to implement the C# post-request code only once in the shared coded of my Xamarin-Forms project?

Answer 1

As #hvaughan3 says you can use HttpClient, like so (from the shared code of your Xamarin Forms project):
private static HttpClient client = new HttpClient() { Timeout = TimeSpan.FromSeconds(30) };
HttpContent content = new StringContent(JsonConvert.SerializeObject(objectToPost), Encoding.UTF8, "application/x-www-form-urlencoded");
var response = await client.PostAsync(new Uri("http://your.url"), content);
if (response.IsSuccessStatusCode) {
var responseFromServer = await response.Content.ReadAsStringAsync();
}
else {
// handle errors
}

Answer 2

Use HTTPcLient for form-URLencoded post request and then create a Custom Webview to handle cookies. Use the CookieWebView Nuget Package created by seansparkman.
Please check https://www.nuget.org/packages/CookieWebView/

Answer 3

POST Request Over Webview
For WkWebview
[assembly: ExportRenderer(typeof(PaymentWebview), typeof(PaymentWebViewRenderer))]
namespace MMFInvestorApp.iOS.Utils
{
public class PaymentWebViewRenderer : WkWebViewRenderer
{
protected override void OnElementChanged(VisualElementChangedEventArgs e)
{
base.OnElementChanged(e);
if (NativeView != null)
{
var request = new NSMutableUrlRequest(new NSUrl(new NSString(paymentwebview.url))); //Your Url
request.HttpMethod = "POST";
request.Body = NSData.FromString(paymentwebview.data); //Data for POST
request["Content-Length"] = req.Body.Length.ToString();
request["Content-Type"] = "application/x-www-form-urlencoded charset=utf-8";
LoadRequest(request);
}
}
}
}
For UIWebview (Deprecated from April 2020
[assembly: ExportRenderer(typeof(PaymentWebview), typeof(PaymentWebViewRenderer))]
namespace MMFInvestorApp.iOS.Utils
{
public class PaymentWebViewRenderer : WebViewRenderer
{
protected override void OnElementChanged(VisualElementChangedEventArgs e)
{
base.OnElementChanged(e);
if (NativeView != null)
{
var paymentwebview = Element as PaymentWebview;
var request = new NSMutableUrlRequest(new NSUrl(new NSString(paymentwebview.url)));//Your Url
request.Body = paymentwebview.data; //Data for POST
request.HttpMethod = "POST";
LoadRequest(request);
}
}
}
}