script to read input from textbox and output response if input is found or not

Question

I need a script that can read input from a textbox on a webpage and output yes or no (or other words) if the input was found in a .txt file

For example, if I have the file of colors located on my website, each separated by ", " and the user puts in "red" and clicks submit, I'd like the next page to say "Yes red is a color". If they input "car" or anything it does not recognize it should return "No car is not a color".