How to execute a command in bat depending on the presence of a substring in a string?

Question

cmd/bat

I'm completely 0 in scripts, tried a lot but nothing happened.
In general, you need to do this in bat:
if there is a substring "xxx" in% computername%, then execute the command [command], otherwise move on

Answer 1

The FIND command returns different ERRORLEVEL values ​​depending on whether the value you are looking for is found or not.
Next in the script, you need to use the if statement.

Answer 2

scriptcoding.ru/2013/08/17/operator-if-cmd

Answer 3

echo %computername% | findstr "xxx" && [command]