通过实例深入理解linux shell数组

${#array}
${#array[0]} #同上。 ${#array[*]} 、${#array[@]}。注意同#{array:0}的区别

array=( [0]=one [1]=two [2]=three [3]=four )
${array[@]:1} # two three four,除掉第一个元素后所有元素，那么${array[@]:0}表示所有元素
${array[@]:0:2} # one two
${array[@]:1:2} # two three

[root@localhost dev]# echo ${array[@]:0}
one two three four

[root@localhost dev]# echo ${array[@]#t*e} # 左边开始最短的匹配:"t*e",这将匹配到"thre"
one two e four

[root@localhost dev]# echo ${array[@]##t*e} # 左边开始最长的匹配,这将匹配到"three"
[root@localhost dev]# array=( [0]=one [1]=two [2]=three [3]=four )

[root@localhost dev]# echo ${array[@] %o} # 从字符串的结尾开始最短的匹配
one tw three four

[root@localhost dev]# echo ${array[@] %%o} # 从字符串的结尾开始最长的匹配
one tw three four

[root@localhost dev]# array=( [0]=one [1]=two [2]=three [3]=four )
第一个匹配到的，会被删除
[root@localhost dev]# echo ${array[@] /o/m}
mne twm three fmur

所有匹配到的，都会被删除
[root@localhost dev]# echo ${array[@] //o/m}
mne twm three fmur

没有指定替换子串，则删除匹配到的子符
[root@localhost dev]# echo ${array[@] //o/}
ne tw three fur

替换字符串前端子串
[root@localhost dev]# echo ${array[@] /#o/k}
kne two three four

替换字符串后端子串
[root@localhost dev]# echo ${array[@] /%o/k}
one twk three four