fix: after handle example

Author: bogeychan

docs/life-cycle/after-handle.md

@@ -15,13 +15,16 @@ head:
 ---
 
 # After Handle
+
 Execute after the main handler, for mapping a returned value of **before handle** and **route handler** into a proper response.
 
 It's recommended to use After Handle in the following situations:
-- Transform requests into a new value, eg. Compression, Event Stream
-- Add custom headers based on the response value, eg. **Content-Type**
+
+-   Transform requests into a new value, eg. Compression, Event Stream
+-   Add custom headers based on the response value, eg. **Content-Type**
 
 ## Example
+
 Below is an example of using the after handle to add HTML content type to response headers.
 
 ```typescript
@@ -32,7 +35,7 @@ new Elysia()
     .get('/', () => '<h1>Hello World</h1>', {
         afterHandle({ response, set }) {
             if (isHtml(response))
-                set.headers['Content-Type'] = 'text/html; charset=utf8'
+                set.headers['content-type'] = 'text/html; charset=utf8'
         }
     })
     .get('/hi', () => '<h1>Hello World</h1>')
@@ -47,28 +50,34 @@ The response should be listed as follows:
 | /hi  | text/plain; charset=utf8 |
 
 ## Returned Value
+
 If a value is returned After Handle will use a return value as a new response value unless the value is **undefined**
 
 The above example could be rewritten as the following:
+
 ```typescript
 import { Elysia } from 'elysia'
 import { isHtml } from '@elysiajs/html'
 
 new Elysia()
     .get('/', () => '<h1>Hello World</h1>', {
         afterHandle({ response, set }) {
-            if (isHtml(response))
+            if (isHtml(response)) {
                 set.headers['content-type'] = 'text/html; charset=utf8'
+                return new Response(response)
+            }
         }
     })
     .get('/hi', () => '<h1>Hello World</h1>')
     .listen(3000)
 ```
 
-Unlike **beforeHandle**, after a value is returned from **afterHandle**, the iteration of afterHandle **will __NOT__ be skipped.**
+Unlike **beforeHandle**, after a value is returned from **afterHandle**, the iteration of afterHandle **will **NOT** be skipped.**
 
 ## Context
+
 `onAfterHandle` Context is extends from `Context` with additional properties of the following:
-- response: Response to return to the client
+
+-   response: Response to return to the client
 
 All of the context is based on normal context and can be used like normal context in route handler.