Fractional quantities or custom quantities by product category

Changes quantity steps by specific product categories. Must be activated on both front and back ends (run everywhere setting).

// Define steps by category
function ccom_get_step_by_product_category( $product_id ) {

	// Categories in priority order
	if( has_term( 'wheels', 'product_cat', $product_id ) ) {
		return 2;
	}
	if( has_term( 'tires', 'product_cat', $product_id ) ) {
		return 2;
	}
	if( has_term( 'fabrics', 'product_cat', $product_id ) ) {
		return 0.25;
	}

	// Default to one
	return 1;
}

// Update min value to the quantity field
add_filter( 'woocommerce_quantity_input_min',
	function( $default, $product ) {

	$product_id = $product->get_id();

	return ccom_get_step_by_product_category( $product_id );

}, 10, 2 );

// Update step value to the quantity field
add_filter( 'woocommerce_quantity_input_step',
	function( $default, $product ) {

	$product_id = $product->get_id();

	return ccom_get_step_by_product_category( $product_id );

}, 10, 2 );

// Replace the WooCommerce filter that is validating the quantity
remove_filter( 'woocommerce_stock_amount', 'intval' );
add_filter( 'woocommerce_stock_amount', 'floatval' );

Instructions for Fractional quantities or custom quantities by product category

  1. Log into a staging or locally hosted clone of your site.
  2. Install and activate Code Snippets plugin.
  3. WP Admin > Snippets > Add New
  4. Copy and paste the code from the section above.
  5. Check to ensure formatting came over properly.
  6. Customize the code as desired.
  7. Add a meaningful title.
  8. Select whether to run on front-end or back-end (or both).
  9. Click “Save and Activate”.
  10. Test your site to ensure it works.
  11. Disable if any problems, or recover.
  12. Repeat for live environment.

Need help modifying Fractional quantities or custom quantities by product category?

Contact me. I can help with fitting projects or refer to my partner.

License

All code snippets are licensed GPLv2 (or later) matching WordPress licensing.

Except when otherwise stated in writing the copyright holders and/or other parties provide the program as-is without warranty of any kind, either expressed or implied, including, but not limited to, the implied warranties of merchantability and fitness for a particular purpose.

Disclaimer of warranty
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