c# - What is the meaning of ToLower().Contains() -

what meaning of given below condition in c#:

if(!dr[4].tostring().tolower().contains("cash")) 

depending on dr (let's not assume things), if outputted string does not contain word 'cash'. breaking down reads:

// if *not* if(!dr[4]      // make single string out of fifth entry of dr (0 first)     .tostring()      // convert characters in lowercase     .tolower()      // check see if has word 'cash' in     .contains("cash"));