Linux Shell 中数组的语法及应用

#!/bin/sh
#
# 数组的声明与初始化方法
# 先声明后赋值:
declare -a array
array=(one two three)

# 声明并初始化：
array_1=(1 2 3 four)

array_2=(
1
2
3
four
)

array_3[0]=1
array_3[1]=2
array_3[2]=3
array_3[3]=four

# 数组元素的引用 ${array_name[index]}
echo "array_1[0]= ${array_1[0]}"    
echo "array_3[3]= ${array_3[3]}"
echo "======================================="

# 数组的引用方法 ${array_name[*]} 或 ${array_name[@]}
echo "First Method: ${array_1[*]}"       
echo "Second Method: ${array_2[*]}"
echo "Third Method: ${array_3[@]}"
echo "======================================="

# $array_name 可直接代表${array_name[0]}
echo $array
echo $array[0]
echo ${#array}
echo "======================================="

# 增加或修改元素(值)
array[4]='hello'      #增加
array[1]='shells'     #修改
echo ${array[*]}
echo ${array[10]}     #空值
echo "======================================="

# 删除元素或数组
unset array[0]
echo ${array[*]}
unset array              #删除数组
echo ${array[*]}
echo "======================================="

# 切片访问  ${array_name[*]:startindex:endindex} or ${array_name[*]:startindex:endindex}     即 array_name[startindex,endindex)
echo ${array_1[*]:1:4}
echo ${array_1[@]:1:7}      #越界显示为空
echo ${array_1[*]:2}          #>=2
echo ${array_1[*]::4}         #<4

echo "======================================="

# 模式替换(匹配并替换)  ${array_name[*]/oldchar/newchar}
array_4=(123 "231" '81o')
echo ${array_4[*]}
echo ${array_4[*]/1/replace}
echo "======================================="

# 数组的长度(元素个数)
arraylength1=${#array_1[@]}
arraylength2=${#array_2[*]}
echo $arraylength1
echo $arraylength2
echo "======================================="

# 元素的长度
elementlength3=${#array_3[3]}
elementlength3_1=${#array_3[1]}
echo $elementlength3
echo $elementlength3_1
echo "======================================="

# 数组的应用(遍历)
for (( n=0; n<${#array_1[@]}; n++ )); do
    echo ${array_1[$n]}
done
echo "======================================="

for I in ${array_1[*]}; do
    echo $I
done
echo "======================================="

# 特殊数组(空格作为元素的分隔符)
for I in `ls -a ~`; do
    echo $I
done

for I in `head -n 10 /etc/passwd | cut -d: -f1`; do
    echo "Username: $I"
done
echo "xxxxxxxxxxxx"

ARRAY=`head -n 10 /etc/passwd | cut -d: -f1`
for I in $ARRAY; do
    echo "Username1: $I"
done

# 参考 http://blog.csdn.net/zhuying_linux/article/details/6778877

源码：

 #!/bin/sh
 #

 # 数组的声明与初始化方法
 # 先声明后赋值:
 declare -a array
 array=(one two three)

 # 声明并初始化：
 array_1=(   four)

 array_2=(

 four
 )

 array_3[]=
 array_3[]=
 array_3[]=
 array_3[]=four

 # 数组元素的引用 ${array_name[index]}
 echo "array_1[0]= ${array_1[0]}"
 echo "array_3[3]= ${array_3[3]}"
 echo "======================================="

 # 数组的引用方法 ${array_name[*]} 或 ${array_name[@]}
 echo "First Method: ${array_1[*]}"
 echo "Second Method: ${array_2[*]}"
 echo "Third Method: ${array_3[@]}"
 echo "======================================="

 # $array_name 可直接代表${array_name[]}
 echo $array
 echo $array[]
 echo ${#array}
 echo "======================================="

 # 增加或修改元素(值)
 array[]='hello'      #增加
 array[]='shells'     #修改
 echo ${array[*]}
 echo ${array[]}     #空值
 echo "======================================="

 # 删除元素或数组
 unset array[]
 echo ${array[*]}
 unset array              #删除数组
 echo ${array[*]}
 echo "======================================="

 # 切片访问  ${array_name[*]:startindex:endindex} or ${array_name[*]:startindex:endindex}     即 array_name[startindex,endindex)
 echo ${array_1[*]::}
 echo ${array_1[@]::}      #越界显示为空
 echo ${array_1[*]:}        #>=
 echo ${array_1[*]::}       #<

 echo "======================================="

 # 模式替换(匹配并替换)  ${array_name[*]/oldchar/newchar}
 array_4=( "" '81o')
 echo ${array_4[*]}
 echo ${array_4[*]//replace}
 echo "======================================="

 # 数组的长度(元素个数)
 arraylength1=${#array_1[@]}
 arraylength2=${#array_2[*]}
 echo $arraylength1
 echo $arraylength2
 echo "======================================="

 # 元素的长度
 elementlength3=${#array_3[]}
 elementlength3_1=${#array_3[]}
 echo $elementlength3
 echo $elementlength3_1
 echo "======================================="

 # 数组的应用(遍历)
 for (( n=; n<${#array_1[@]}; n++ )); do
     echo ${array_1[$n]}
 done
 echo "======================================="

 for I in ${array_1[*]}; do
     echo $I
 done
 echo "======================================="

 # 特殊数组(空格作为元素的分隔符)
 for I in `ls -a ~`; do
     echo $I
 done

 for I in `head -n  /etc/passwd | cut -d: -f1`; do
     echo "Username: $I"
 done
 echo "xxxxxxxxxxxx"

 ARRAY=`head -n  /etc/passwd | cut -d: -f1`
 for I in $ARRAY; do
     echo "Username1: $I"
 done

 # 参考 http://blog.csdn.net/zhuying_linux/article/details/6778877

array.sh