Finding and repeating a character

[Rostrox]

Hi: Trying to know more about C# and its libraries ... Without using explicit iterations, how could I: 1) Determine if a character is in a list of characters? For example if I want to know if the content of variable v is in a list containg 'a','j','1','%'. I normally do: if (v[i] == 'a' || v[i] == 'j' ..... but it is too long if I use with many characters in the list. I would like something like (if a[i] in ('a','j','1','%')) for example. 2) For writing the character ',' 600 times I would like to do this: write(600(',')), for example and not use for statement. Seems to be disheveled but :rolleyes:.... May there may be alternatives. Best regards