我想写一个循环15个字符串的脚本(可能是数组?)这可能吗?
类似于:
for databaseName in listOfNames
then
# Do something
end
我想写一个循环15个字符串的脚本(可能是数组?)这可能吗?
类似于:
for databaseName in listOfNames
then
# Do something
end
当前回答
单线循环,
declare -a listOfNames=('db_a' 'db_b' 'db_c')
for databaseName in ${listOfNames[@]}; do echo $databaseName; done;
你会得到这样的输出,
db_a
db_b
db_c
其他回答
我循环浏览一系列项目以进行git pull更新:
#!/bin/sh
projects="
web
ios
android
"
for project in $projects do
cd $HOME/develop/$project && git pull
end
脚本或函数的隐式数组:
除了anubhava的正确答案:如果循环的基本语法是:
for var in "${arr[@]}" ;do ...$var... ;done
bash中有一个特殊情况:
当运行脚本或函数时,在命令行传递的参数将被分配给$@数组变量,您可以通过$1、$2、$3等进行访问。
可以通过以下方式填充(用于测试)
set -- arg1 arg2 arg3 ...
这个数组上的循环可以简单地写:
for item ;do
echo "This is item: $item."
done
请注意,中的保留工作不存在,也没有数组名称!
示例:
set -- arg1 arg2 arg3 ...
for item ;do
echo "This is item: $item."
done
This is item: arg1.
This is item: arg2.
This is item: arg3.
This is item: ....
注意,这与
for item in "$@";do
echo "This is item: $item."
done
然后进入脚本:
#!/bin/bash
for item ;do
printf "Doing something with '%s'.\n" "$item"
done
将其保存在脚本myscript.sh、chmod+x myscript.shh中,然后
./myscript.sh arg1 arg2 arg3 ...
Doing something with 'arg1'.
Doing something with 'arg2'.
Doing something with 'arg3'.
Doing something with '...'.
在函数中相同:
myfunc() { for item;do cat <<<"Working about '$item'."; done ; }
Then
myfunc item1 tiem2 time3
Working about 'item1'.
Working about 'tiem2'.
Working about 'time3'.
如果您使用的是Korn shell,则有“set-A databaseName”,否则有“declare-A databaseName”
要在所有外壳上编写脚本,
set -A databaseName=("db1" "db2" ....) ||
declare -a databaseName=("db1" "db2" ....)
# now loop
for dbname in "${arr[@]}"
do
echo "$dbname" # or whatever
done
它应该在所有外壳上工作。
listOfNames="db_one db_two db_three"
for databaseName in $listOfNames
do
echo $databaseName
done
或者只是
for databaseName in db_one db_two db_three
do
echo $databaseName
done
这些答案中没有一个包含计数器。。。
#!/bin/bash
## declare an array variable
declare -a array=("one" "two" "three")
# get length of an array
arraylength=${#array[@]}
# use for loop to read all values and indexes
for (( i=0; i<${arraylength}; i++ ));
do
echo "index: $i, value: ${array[$i]}"
done
输出:
index: 0, value: one
index: 1, value: two
index: 2, value: three