shell数组常见操作

#!/bin/bash

#声明数组
declare -a TEST

#j=0
#cat > test.file << EOF
#1
#2
#3
#4
#5
#EOF
#将文件的值写入到数组中
#for line in $(cat test.file)
#do
#       TEST[${j}]=${line}
#       let j+=1
#done

#定义数组内容
TEST[0]=1
TEST[1]=2
TEST[2]=3
TEST[3]=4
TEST[4]=5
#打印数组内容
echo ${TEST[@]}

#打印数组所有元素：${ARRAY_NAME[@]} or ${ARRAY_NAME[*]}

#打印数组元素 方式一
echo "one way to print all of the array elements"
for i in ${TEST[@]}
do
echo ${i}
done

#打印数组元素 方式二
echo "another way to print all of the array elements"
for i in ${TEST[*]}
do
echo ${i}
done

#获取数组长度
#法一
echo "get array length"
echo "solution 1"
echo ${#TEST[*]}
echo "solution 2"
#法二
echo ${#TEST[@]}

#打印数组的第四个元素
echo "print the fourth array element"
echo ${TEST[3]}

#删除数组的第四个元素
echo "delete fourth array element"
unset TEST[3]

for i in ${TEST[@]}
do
echo ${i}
done

#删除整个数组，删除后不会再打印数组元素
unset TEST

for i in ${TEST[@]}
do
echo ${i}
done

[root@test ~]# sh a.sh
1 2 3 4 5
one way to print all of the array elements
1
2
3
4
5
another way to print all of the array elements
1
2
3
4
5
get array length
solution 1
5
solution 2
5
print the fourth array element
4
delete fourth array element  #此处可以看到没有打印出已删除的数组元素4
1
2
3
5