Http Callout to Rest API from apex

Question

How to send request and get response from server when working with Rest API.

Answer 1

 Http http1=new Http();
 HttpRequest req1=new HttpRequest();
 req1.setendpoint('URL');
 req1.Setheader('String','String');
 req1.setmethod('POST'); //you can also SET method `GET` with Get there is no need of req1.setbody()
 req1.setbody(string);
 HttpResponse res1;
 res1 = http1.send(req1);
 String str=res1.getbody();

Answer 2

The details of making HTTP callouts in Apex are found in the developer.force.com wiki pages here:

http://wiki.developerforce.com/page/Apex_Web_Services_and_Callouts

Answer 3

These Is How You Can Send A request or get Response

public class pincode {

public string x {get;set;}
    public PageReference click() {

   http p = new http();// invoiking Http Class
httprequest req= new httprequest(); //Invoking RestRequest
req.setEndpoint('http://pin-codes.in/api/pincode/500072');//Setting Endpoint
req.setMethod('GET');// Setting Method 
httpresponse res = new httpresponse();
res=p.send(req);
system.debug('-------'+req.getBody());
x= res.getbody();// Catching Response 
        return null;
    }

}