如何从getopts中获取2个参数

#!/bin/bash

while getopts ":a:b:" opt; do
  case $opt in
    a)
      arg1=$OPTARG
      ;;
    b)
      arg2=$OPTARG
      ;;
    \?)
      echo "无效的选项: -$OPTARG" >&2
      exit 1
      ;;
    :)
      echo "选项 -$OPTARG 需要参数." >&2
      exit 1
      ;;
  esac
done

echo "参数1: $arg1"
echo "参数2: $arg2"

$ ./script.sh -a value1 -b value2
参数1: value1
参数2: value2