我有下面的Map

Map<String, String> Dictionary = {
    '37': 'thirty-four',
    '94': 'ninety',
    '91': 'ninety-one',
    '22': 'twenty-one',
    '61': 'sixty-one',
    '9': 'nine',
    '3': 'three',
    '8': 'eight',
    '80': 'eighty',
    '81': 'eighty-one',
    'Ninety-eight': '98',
    'nine-hundred': '900'};

我想按升序排序，这样最终结果是

3: three
8: eight
9: nine
22: twenty-two
37: thirty-seven
61: sixty-one
80: eighty
81: eighty-one
91: ninety-one
94: ninety four
Ninety-eight': 98
nine-hundred': 900

但是我得到的结果是

22: twenty-two
3: three
37: thirty-seven
61: sixty-one
8: eight
80: eighty
81: eighty-one
9: nine
91: ninety-one
94: ninety-four
Ninety-eight: 98
nine-hundred: 900

以上结果的代码如下

sortDict(){

    var sortedByKeyMap = Map.fromEntries(
        Dictionary.entries.toList()..sort((e1, e2) => (e1.key).compareTo((e2.key))));

    print(sortedByKeyMap);

  }

你知道如何先将数字字符串键转换为int吗？