批处理：获取字符串的第一个字母

Question

目前正在测试一些东西，想知道是否可以获取字符串的第一个字母并将其分配给变量？

一些context/example：

set USRDIR1==\SERVER\Users\%username%
if not exist %USRDIR1% mdkir %USRDIR1%

rem // grab first letter from %username% and assign to %firstletter% //

set USDIR2==\SERVER\Users\%firstletter%\%Username%
if not exist %USRDIR2% mkdir %USRDIR2%

Answer 1

set USRDIR1==\SERVER\Users\%username%
if not exist %USRDIR1% mdkir %USRDIR1%

rem // grab first letter from %username% and assign to %firstletter% //
set firstletter=%username:~0,1%

set USDIR2==\SERVER\Users\%firstletter%\%Username%
if not exist %USRDIR2% mkdir %USRDIR2%

Check variable substring syntax

批处理：获取字符串的第一个字母

Batch: Grab first letter of a string

batch-file