How to use toLowerCase() function before filter?

I want to lowercase product.productName before filter, but I couldn’t do that. I tried some thing but didn’t work. Is there any way that I can lowercase product.productName before filter?

>Solution :

Simply convert to lowercase inside filter before comparing.
e.g.
product.productName.toLowerCase().includes .....

If it complains about being an object, convert to string first.

product.productName.toString().toLowerCase().includes ....