SKU defined in Custom option is displayed in Magento in the product page

Issue background:

Now selling a book, in English and Spanish, requires customers to choose their own language version. Therefore, when defining a product, define its custom option and add the appropriate version of the entry.

The front desk will show

It is now required to display its SKU under each entry.

Workaround:

1. Find app\code\local\mage\catalog\block\product\view\options\type\select.php

2. Add an Output SKU statement to the 103-line statement in the file

$selectHtml. = ' <li> '.
                               ' <input type= "'. $type. '" class= "'. $class. ' '. $require. ' Product-custom-option ' onclick= "Opconfig.reloadprice ()" Name= "options[". $_option->getid (). $arraySign. ' "id=" Options_ '. $_option->getid (). ' _ '. $count. ' value= '. $_value->getoptiontypeid (). '/> '.
                               ' <span class= "label" ><label for= "Options_". $_option->getid (). ' _ '. $count. ' " > '. $_value->gettitle (). ' '. $priceStr. ' </label><br><label> '. $_value->getsku (). ' </label></span> ';