Pursuing research before applying to grad schools I graduated last year (Bachelors in Computer Science) and am currently working in the industry. I am thinking of applying to grad schools next year but don't have any research experience under my belt (did not pursue any research-oriented project during my undergrad, regret it now).

Therefore I was thinking of pursuing research under a professor before applying for masters (to get a good LoR, as well as get in a publication, if possible). In what circumstances do professors take up requests such as mine, and how should I approach him/her? Currently I am shortlisting the ongoing research projects relevant to my field of interest in prospective universities.
EXACTLY   HOW do to define " research  experience"?
 You may have  more  research  experience  than  you  thin,k. Bow many  term papers Din;t  you do ANY LIBRARY RESEARCH  for term  papers  during  middle  school,  high school  or  college,  no matter   what  your  major  was  in  college?  Library  research IS RESEARCH. I learned  how  to  write   term papers  with  footnotes   and  reference  lists  in  7th  and  8th  grade  more  than  50  years ago.   There  was  section  of  "how  to  use  the  library  in  English class in  both  grade  school   and  the  (th  grade.  That  i went  to private  college  prepatory  schools  in  the  United  states  is  NOT  that  unique,  "how  to use'  the  library  was  also   taught  in public  schools.  in  the  USA. 
Apparently  how  to use   a  search  engine  is  not  being  taught  at  all.  I've  been using  Google  since  1993  or  1994,  but  i went  to  back  to  college  in 1992  just  as  the  internet  was  taking  off    in higher  education.

"...Undergraduate research experiences help students understand a particular topic or phenomenon in a field while simultaneously strengthening their comprehension of research and research methods. Undergraduate research is inquiry-based learning that involves practicing a discipline, not just being told about it...."
https://serc.carleton.edu/introgeo/studentresearch/What.html 

You probably DO  have  research  experience  and  do not  realize  because  your  haven't  bothered   to look up   the  definition   of  "research  experience."  I LOVE  doing  library  research,   but  i know  most  people   think  library  research  is  waste  of  time    and  is  boring  and  tedious  until  they  get  stuck   and HAVE  to  review  the professional  literature   and KEEP UP   with  it    g  for the  REQUIREMENTS  for  specific  college  degree   and  have  to  either  numerous  term papers  or  senior  thesis  which  requires   library  research,  possible  lab   research  compiling  data.   and  even  Field  work   to  father  more  data  or  field  truthingt  and  verification like  i   did  for  my  master's  thsis,  that  what  is  in  ssatellite  image  and  geological  maps  really IS  there  on  the  ground   and  is  real  and  is  accurate..

Part of  the point  of    going  to  college  these  days  is  to    teach you HOW TO THINK  critically , logically,  analytically  and  objectively  AND     so you   acquire  the  research  skills  to KEEP  doing your  own  research  AND   contribute  original knowledge  to  society.

You probably DO have   research   experience.

I  am  still  getting  used  to how  stack  exchanges  work  too. I  am  AMAZED  at  how much research i  can  do  online    these   without  having  to  get  anywhere  near  a  brick  and  mortar  library.