怎样判断变量是否为空

cl02050212

怎样判断变量是否为空

linux_paly

1. 
   
2. #!/bin/bash
   
3. a="zzz"
   
4. if [[ "$a" = "" ]]
   
5. then
   
6. echo $a empty
   
7. else
   
8. echo $a no empty
   
9. fi
   

复制代码

foreman2002

if [[ "${a}aa" = "aa" ]]

BLZer

if [ -z "$VAR" ] ; then
command
fi

mcolinc

[ -z "$var" ] && echo "empty" || echo "not empty"

a8e8c1ca5b

不错