shell 判斷字符串長度是否為0

 

test.sh

#!/bin/bash
echo "enter the string:"
read filename
if test -z $filename ; then
echo "the length is 0"
else
echo "the length is not 0"
fi

執行

sudo chmod +x test.sh
./test.sh

輸出

enter the string:

the length is 0

 

執行

./test.sh

輸出

enter the string:
sssssss
the length is not 0