C# 使用group by进行LINQ查询时的帮助
我有以下清单:C# 使用group by进行LINQ查询时的帮助,c#,linq-to-objects,C#,Linq To Objects,我有以下清单: 1: true; 2: false; 2: true; 3: false; 3: false; 3: false; 我希望LINQ查询获得如下集合: 键,或分组项之间的操作,例如: 2: false | true = true 结果必须是: 1: true 2: true 3: false 提前谢谢 // my sample data var list = new[] { new {key = 1, value = true}
1: true;
2: false;
2: true;
3: false;
3: false;
3: false;
我希望LINQ查询获得如下集合:
键,或分组项之间的操作,例如:
2: false | true = true
结果必须是:
1: true
2: true
3: false
提前谢谢
// my sample data
var list = new[] {
new {key = 1, value = true},
new {key = 2, value = false},
new {key = 2, value = true},
new {key = 3, value = false},
new {key = 3, value = false},
new {key = 3, value = false},
};
// the actual code
var groups = from pair in list
group pair by pair.key into grp
orderby grp.Key
select new {
grp.Key,
Value = grp.Aggregate(false, (x, y) => x || y.value)
};
// display the result
foreach (var grp in groups)
{
Console.WriteLine("{0}: {1}", grp.Key, grp.Value);
}
注意:您也可以使用Any
进行聚合,其优点是它会更快短路:
select new { grp.Key, Value = grp.Any(y => y.value) };