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public class TestClass
{
public string userName { get; set; }
public int Age { get; set; }
public string QQCode { get; set; }
}
List<TestClass> tests = new List<TestClass>();
tests.Add(new TestClass { userName = "张三", Age = 12, QQCode = "11111" });
tests.Add(new TestClass { userName = "张三", Age = 12, QQCode = "22222" });
tests.Add(new TestClass { userName = "李四", Age = 13, QQCode = "33333" });
tests.Add(new TestClass { userName = "李四", Age = 13, QQCode = "44444" });
tests.Add(new TestClass { userName = "李四", Age = 13, QQCode = "55555" });
tests.Add(new TestClass { userName = "王五", Age = 14, QQCode = "66666" });
tests.Add(new TestClass { userName = "赵六", Age = 15, QQCode = "77777" });
var v = from p in tests
group p by p.userName into g
select new {
userName =g.Key,
Count=g.Count() ,
QQCodes=???
};
var result = tests.Where(tc => tc.userName == "李四").Select(qq => qq.QQCode);
string qqCodes = string.Join(",", result.ToArray());
或者这样也可以
var result = from tc in tests where tc.userName == "李四" select tc.QQCode;
string qqCodes = string.Join(",", result.ToArray());
var v = from p in tests
group p by p.userName into g
select new {
userName =g.Key,
Count=g.Count() ,
QQCodes = string.Join(",", g.Select(y => y.QQCode.ToString()).ToArray())
};
//或者下面这样
var v1 = tests.GroupBy(p => p.userName).Select(p => new {
userName = p.Key,
Count = p.Count(),
QQCodes = string.Join(",", p.Select(y => y.QQCode.ToString()).ToArray())
});