Linux 变量作为bash数组索引？
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Variable as bash array index?
提问by John Hansen
#!/bin/bash
set -x
array_counter=0
array_value=1
array=(0 0 0)
for number in ${array[@]}
do
array[$array_counter]="$array_value"
array_counter=$(($array_counter + 1))
done
When running above script I get the following debug output:
运行上述脚本时，我得到以下调试输出：
+ array_counter=0
+ array_value=1
+ array=(0 0 0)
+ for number in '${array[@]}'
+ array[$array_counter]=1
+ array_counter=1
+ for number in '${array[@]}'
+ array[$array_counter]=1
+ array_counter=2
+ for number in '${array[@]}'
+ array[$array_counter]=1
+ array_counter=3
Why does the variable $array_counternot expand when used as index in array[]?
为什么变量$array_counter在用作数组 [] 中的索引时不会扩展？
回答by Bob the Angry Coder
Bash seems perfectly happy with variables as array indexes:
Bash 似乎对变量作为数组索引非常满意：
$ array=(a b c)
$ arrayindex=2
$ echo ${array[$arrayindex]}
c
$ array[$arrayindex]=MONKEY
$ echo ${array[$arrayindex]}
MONKEY
回答by user2038893
Your example actually works.
你的例子确实有效。
echo ${array[@]}
confirms this.
证实了这一点。
You might try more efficient way of incrementing your index:
您可以尝试更有效的增加索引的方法：
((array_counter++))
