Hi

I am very new to Lightning Development. I am trying to learning developing Lightning components on my own.
I was trying to develop an Input form for Case Object. Now, I wanted to Attach files feature as well to the form at the very bottom.
Once I upload and save the form, a new Case record should be created with attachments in the record detail page.

I have used this to get the Input for upload a file:
 

<lightning:input type="file" label="Attachment" name="file" multiple="true" aura:id = "upButton" accept="image/png, .zip" onchange="{! c.handleFilesChange }"/>

Can someone share a simple code for the controller(handleFilesChange) as well as the Server-side class to save the data to Case object.

Thanks!