文件相关

-d：检查是否为目录（directory）

if [ -d "/path/to/directory" ]; then
    echo "It's a directory."
fi

-f：检查是否为普通文件（file)

if [ -f "/path/to/file" ]; then
    echo "It's a regular file."
fi

-e：检查文件是否存在

if [ -e "/path/to/file" ]; then
    echo "The file exists."
fi

-s：检查文件是否非空

if [ -s "/path/to/file" ]; then
    echo "The file is not empty."
fi

-r：检查文件是否可读

if [ -r "/path/to/file" ]; then
    echo "The file is readable."
fi

-w：检查文件是否可写

if [ -w "/path/to/file" ]; then
    echo "The file is writable."
fi

-x：检查文件是否可执行

if [ -x "/path/to/file" ]; then
    echo "The file is executable."
fi

字符串

-n：检查字符串是否非空

string="Hello, World!"
if [ -n "$string" ]; then
    echo "The string is not empty."
fi

-z：检查字符串是否为空

string="Hello, World!"
if [ -z "$string" ]; then
    echo "The string is not empty."
fi

算术

-eq：检查两个整数是否相等

number1=10
number2=20
if [ "$number1" -eq "$number2" ]; then
    echo "The numbers are equal."
fi

-ne：检查两个整数是否不相等

number1=10
number2=20
if [ "$number1" -ne "$number2" ]; then
    echo "The numbers are not equal."
fi

-gt：检查第一个整数是否大于第二个整数

number1=30
number2=20
if [ "$number1" -gt "$number2" ]; then
    echo "The first number is greater than the second number."
fi

-lt：检查第一个整数是否小于第二个整数

number1=10
number2=20
if [ "$number1" -lt "$number2" ]; then
    echo "The first number is less than the second number."
fi

-ge：检查第一个整数是否大于等于第二个整数

number1=30
number2=20
if [ "$number1" -ge "$number2" ]; then
    echo "The first number is greater than or equal to the second number."
fi

-le：检查第一个整数是否小于等于第二个整数

number1=10
number2=20
if [ "$number1" -le "$number2" ]; then
    echo "The first number is less than or equal to the second number."
fi