htmlifelse语句例子（html中if可以嵌套while吗）

#ifelse_exam.sh脚本用于检查输入的字符串是否是一个当前目录

#!/bin/bash

if [ "$1" ]

then

echo "What you input is not null"

if [ -e "$1" ]

then

echo "The file $1 is existence!"

else

echo "The file $1 is not existence!"

fi

else

echo "What you input is null!"

fi