function override

You can’t override those files / functions. What are you trying to do exactly?

You should be able to use this filter: https://github.com/woothemes/woocommerce/blob/a8e47992a69fcca0393114afc387f85f5289e9ea/includes/class-wc-form-handler.php#L566

Thanks for quick response but I need to not files override but only function override

See following woo-commerce core function override how can do this?

function update_cart_action()
{
content here…
}
above function is core but i have some changed thay why i need to override this function

Again, you can’t override those files / functions. What are you trying to do exactly?

You should be able to use this filter: https://github.com/woothemes/woocommerce/blob/a8e47992a69fcca0393114afc387f85f5289e9ea/includes/class-wc-form-handler.php#L566 instead of overriding the function.

Is there a way we can override the core “include” class files? e.g – class-wc-form-handler.php?

I want to override the function – update_cart_action() in a way that it should not return a message when the user removes an item from cart.

I tried to comment out the below line and it worked fine.
//wc_add_notice( $removed_notice );

But I do not want to update the core file. Instead I want to override and update.

Please help.