如何在 Linux shell 脚本中提示输入后调用函数？

Question

标题说明了一切。在我被提示后，我希望 yes 和 no 分别调用一个函数。

# Check to see if you ran this script before

echo
echo I need to know if this is your first time...
while true; do
    read -p "" yn
        case $yn in
            [Yy]* ) new;;
            [Nn]* ) exit;;
                * ) echo "Please answer yes or no.";;
            esac
done

# Define function as new
new (){
    clear; echo As you are new, I will need a few things.
} 

# Define function as root

root(){
    echo "$(tput setaf 6)Hello, world$(tput sgr0)"
}
echo

如果用户输入“y”，我希望脚本调用函数“new”。现在，脚本将尝试运行一个名为“new”的不存在的程序。哈哈。谢谢

Answer 1

您需要在调用函数之前定义它们：

# Define function as new
new (){
    clear; echo As you are new, I will need a few things.
} 

# Check to see if you ran this script before
echo
echo I need to know if this is your first time...
while true; do
    read -p "" yn
        case $yn in
            [Yy]* ) new;;
            [Nn]* ) exit;;
                * ) echo "Please answer yes or no.";;
            esac
done

Answer 2

假设这是 bash，脚本中的每一行都将从最小到最大读取。即“第 1 行，然后是第 2 行，然后是第 3 行，依此类推。考虑到这一点，您可以在脚本中创建许多函数，并依次调用它们，如下所示：

#!/bin/bash

func_1() {
echo "Doing something."
}

func_2() {
echo "Doing something again."
}

func_3() {
echo "Doing something for the last time."
}

func_1
func_2
func_3

但是，为了调用每个函数，调用总是必须在定义之后，如下所示：

#!/bin/bash

func_1() {
echo "Doing something."
}

func_2() {
echo "Doing something again."
}

func_3() {
echo "Doing something for the last time."
}

until [ "$SOMETHING" == "SOMETHING_1" ]
do
func_1
done

until [ "$SOMETHING_2" == "SOMETHING_3" ]
do
func_2
done

until [ "$SOMETHING_4" == "SOMETHING_5" ]
do
func_3
done

这将有助于更好地利用更复杂脚本中的函数。希望这能有所帮助。