function readOnly(count){ }
Starting November 20, the site will be set to read-only. On December 4, 2023,
forum discussions will move to the Trailblazer Community.
+ Start a Discussion
srujith chintha 4srujith chintha 4 

callout class

public class CalloutClass { @future(callout=true) public static void makeCallout() { HttpRequest request = new HttpRequest(); // Set the endpoint URL. String endpoint = 'http://yourHost/yourService'; request.setEndPoint(endpoint); // Set the HTTP verb to GET. request.setMethod('GET'); // Send the HTTP request and get the response. HttpResponse response = new HTTP().send(request); } }

1.how to make callout by adding trigger
 
AbhinavAbhinav (Salesforce Developers) 
Check this:

https://salesforce.stackexchange.com/questions/5602/http-callout-from-triggers

Thanks!