Update examples/tutorial/step_3.wiki

examples/tutorial/step_3.wiki

@@ -12,6 +12,43 @@ or go to [[step_4.wiki|step 4]]
 == "hello" project ==
 * Let's start from the "hello_custom" project
 * you will learn how to use the req: WSF_REQUEST argument
+* See the hello project from [[step_3]] folder
+
+* The code looks like
+
+   response (req: WSF_REQUEST): WSF_HTML_PAGE_RESPONSE
+ 			-- Computed response message.
+ 		do
+ 			--| It is now returning a WSF_HTML_PAGE_RESPONSE
+ 			--| Since it is easier for building html page
+ 			create Result.make
+ 			Result.set_title ("EWF tutorial / Hello World!")
+ 			--| Check if the request contains a parameter named "user"
+ 			--| this could be a query, or a form parameter
+ 			if attached req.string_item ("user") as f_user then
+ 				--| If yes, say hello world #name
+ 				Result.set_body ("Hello " + f_user.string + "!")
+ 				--| We should html encode this name
+ 				--| but to keep the example simple, we don't do that for now.
+ 			else
+ 				--| Otherwise, ask for name
+ 				Result.set_body ("[
+ 							<form action="/" method="POST">
+ 								<p>Hello, what is your name?</p>
+ 								<input type="text" name="user"/>
+ 								<input type="submit" value="Validate"/>
+ 							</form>
+ 						]"
+ 					)
+ 			end
+      --| note:
+      --| 1) Source of the parameter, we could have used
+ 			--|		 req.query_parameter ("user") to search only in the query string
+ 			--|		 req.form_parameter ("user") to search only in the form parameters
+ 			--| 2) response type
+ 			--| 	it could also have used WSF_PAGE_REPONSE, and build the html in the code
+ 			--|
+ 		end
 
 ----