由网友(|放生∮Melody)分享简介：如何从词典中删除所有重复使用LINQ的声明看起来像这样：How to remove all duplicates with a LINQ statement from a dictionary looking like this:Dictionary()2型包含字符串属性ID。我想删除具...

如何从词典中删除所有重复使用LINQ的声明看起来像这样：

How to remove all duplicates with a LINQ statement from a dictionary looking like this:

Dictionary<Type1, Type2>()

2型包含字符串属性ID。我想删除具有相同ID的所有条目

Type2 contains a string property ID. I want to remove all entries that has the same ID

推荐答案

可以组要和特定领域的字典中，然后拿到的第一个值匹配（或全部）：

You can group the dictionary on a specific field you want to, and then get the first value matching (or all):

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);
}

或者，如果你不小心创造结果的新词典：

Or if you don't care to create a new dictionary for the results:

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

var d2 = d.GroupBy(x => x.Value.SomeId)
          .ToDictionary(x => x.First().Key, x => x.First().Value)
          ;