linux - Shell 脚本大小写语法错误

Question

尝试运行以下命令时，我在 vi 中不断收到以下语法错误“语法错误接近意外标记‘case’”:

 #!/bin/bash
if [ -z $1 ]
then
        NAME="Person"
elif [ -n $1 ]
then
        NAME=$1
fi

for NAME
case $NAME in
        "Alice") echo "$NAME is a member of the name group.";;
        "Bob") echo "$NAME is a member of the name group.";;
        "Charlie") echo "$NAME is a member of the name group.";;
        "Quan") echo "$NAME is a member of the name group.";;
        "Brandon") echo "$NAME is a member of the name group.";;
        *) echo "Sorry, That $NAME is not a member of the name group.";;
esac

Answer 1

#!/bin/bash
#Will also work with dash (/bin/sh)

#Shorter default-value assignment
#+ no need for an all-cap variable
name="$1" 
: "${name:=Person}"

#`for name` doesn't belong here
case "$name" in
        "Alice") echo "$name is a member of the name group.";;
        "Bob") echo "$name is a member of the name group.";;
        "Charlie") echo "$name is a member of the name group.";;
        "Quan") echo "$name is a member of the name group.";;
        "Brandon") echo "$name is a member of the name group.";;
        *) echo "Sorry, That $name is not a member of the name group.";;
esac

全大写变量通常用于:

• 从环境导出或继承的变量
• 配置shell的变量

如果两者都不适用，则无需全部大写。

默认情况下引用 "$variables" 是一个很好的做法，除非您特别希望在空白处进行拆分(或者更准确地说是 $IFS)。