Question

如何使用字典中的LINQ语句删除所有重复项：

Dictionary<Type1, Type2>()

Type2包含字符串属性ID。我想删除所有具有相同ID的条目

Answer 1

您可以将字典分组到您想要的特定字段，然后获得匹配（或全部）的第一个值：

Traceback (most recent call last):
  File "C:\path\to\py\ssltest.py", line 4, in <module>
    r = requests.get('https://localhost:8081/api', cert=r'C:\path\to\cert\mule.crt')
  File "C:\Python34\lib\site-packages\requests\api.py", line 69, in get
    return request('get', url, params=params, **kwargs)
  File "C:\Python34\lib\site-packages\requests\api.py", line 50, in request
    response = session.request(method=method, url=url, **kwargs)
  File "C:\Python34\lib\site-packages\requests\sessions.py", line 465, in request
    resp = self.send(prep, **send_kwargs)
  File "C:\Python34\lib\site-packages\requests\sessions.py", line 573, in send
    r = adapter.send(request, **kwargs)
  File "C:\Python34\lib\site-packages\requests\adapters.py", line 431, in send
    raise SSLError(e, request=request)
requests.exceptions.SSLError: [SSL] PEM lib (_ssl.c:2536)

或者，如果您不在乎为结果创建新词典：

Dictionary<Type1, Type2> d = new Dictionary<Type1, Type2>();

var entriesToBeRemoved = d.GroupBy(x => x.Value.SomeId)
                         .SelectMany(x => x.Skip(1))
                         .ToList()
                         ;

foreach (var kvp in entriesToBeRemoved)
{
    d.Remove(kvp.Key);
}

Answer 2

这应该完全按照您的要求运作：

var removables =
    dict
        .ToLookup(x => x.Value.ID, x => x.Key)
        .SelectMany(x => x.Skip(1))
        .ToArray();

foreach (var key in removables)
{
    dict.Remove(key);
}

根据Value中的属性，从对象的字典中删除重复项

2 个答案: