原文地址：http://ju.outofmemory.cn/entry/218410
1.通配符
string='My long string'
if [[ $string == *"My long"* ]]; then
echo "It's there!"
fi
2.正则匹配
string='My long string'
if [[ $string =~ .*My.* ]]; then
echo "It's there!"
fi
3.switch…case版本的通配符(速度最快……)
string='My long string'
case "$string" in
*foo*)
# Do stuff
;;
esac
4.用grep来实现
string='My long string'
if grep -q foo <<<$string; then
echo "It's there"
fi
5.用字符串替换/删除来实现
string='My long string'
if [ "$string" != "${string/foo/}" ]; then
echo "It's there!"
fi
