在bash

Question

由另一个替换一个子我有以下bash脚本

pass="kall" 
cnumb="000000000000" 

for ((i=0; i<${#pass}; i++)) 
do 
    code=`printf '%03d' "'${pass:i:i+1}"` #generate the code ASCII of letter as string with 3 chars 
    cnumb = .... #put the code ASCII of "k" in the first bloc of 3 chars , put the code ASCII of "a" in the second bloc of 3 chars, ... 
done 

如在代码所描述的，我想repace在循环每次迭代的3个字符的cnumb一个集团由另一3个charachters集团。如何用bash执行此操作

是否可以用代码替换子字符串${cnumb:i:i+3}？

Answer 1

无需将零置入cnumb。此外，使用%03d模板printf：

#! /bin/bash 
pass="kall" 
cnumb='' 

for ((i=0; i<${#pass}; i++)) 
do 
    code=`printf '%03d' "'${pass:i:i+1}"` #generate the code ASCII of letter as string with 3 chars 
    cnumb+=$code 
done 
echo "$cnumb"