remove all non-alphanumeric characters from lua string

Question

I checking string for a non-alphanumeric char.

if(str:match("%W")) then
  --make str alpha-numeric
end

How to remove all non-alphanumeric chars from string using lua?

Answer 1

Use gsub (as suggested by Egor Skriptunoff):

str = str:gsub('%W','')

Answer 2

just make it like this you forgot +

if(str:match("%W+")) then --if it contain alpha
     number = str:match("%d+")
     alpha = str:match("%W+")
 end