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如何将变数设定为违约值?
原标题:How to set a variable to default value?
  • 时间:2010-11-19 10:34:19
  •  标签:
  • bash
  • shell

以下守则正在按预期对用户投入进行检查。

if [ -z "$1" ]
then
myvar= 80 
else
myvar="$1"
fi  

但我读到了非常简短的同文。 任何要点?

最佳回答

你可以做到:

myvar=${1:-"80"}
问题回答

暂无回答




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