[VB6] StringBuilder - Fast string concatenation-VBForums
https://www.vbforums.com/showthread....-concatenation

like this,it's use Append (s="abc", append "ddd",s ="abcddd")
i like chage sub name to "add"
it's not addline,so i need change use:
sub addline(s)
append "ddd"
append vbcrlf
end sub

It also takes a lot of time to learn the process usage inside