shell字符串索引

Posted 2020-08-29 Sawyer Ford

shell中的字符串索引一会从0开始，一会从1开始，见例子：

#!/bin/bash

string="hello world"
length=${#string}
echo "string is \\""$string"\\""
echo "length is $length"

index=`expr index "$string" \'o\'`
echo "index of \'o\' is $index"

substring=${string:$index}
echo "substring begins from index $index is \\""$substring"\\""
echo "shit happens"
echo

exit 0

输出如下：