在linq查询中使用最小值和最大值进行区分

我有一张像下面这样的桌子

Name Entrytime    Exittime
A    10:30 AM     6:30PM    
A    7:30 AM      5:30PM
B    10:30 AM     2:30PM
A    5:30 AM      3:30PM
B    11:30 AM     4:30PM
A    8:30 AM     7:30PM
C    9:30 AM      1:30PM
C    10:30 AM     9:30PM

Name Entrytime    Exittime
A    5:30 AM      7:30PM    
B    10:30 AM     4:30PM
C    9:30 AM      9:30PM

我需要使用linq查询获取每个名称的记录最小输入时间和每个名称的最大退出时间

所以我需要下面这样的结果集

Name Entrytime    Exittime
A    10:30 AM     6:30PM    
A    7:30 AM      5:30PM
B    10:30 AM     2:30PM
A    5:30 AM      3:30PM
B    11:30 AM     4:30PM
A    8:30 AM     7:30PM
C    9:30 AM      1:30PM
C    10:30 AM     9:30PM

Name Entrytime    Exittime
A    5:30 AM      7:30PM    
B    10:30 AM     4:30PM
C    9:30 AM      9:30PM

下面是一个LinqPad查询，显示了当Entrytime和Exittime是字符串而不是datetime时，如何在IEnumerable上执行此操作：

var list= new[]{
new {Name="A",Entrytime="10:30 AM",Exittime="6:30PM"},
new {Name="A",Entrytime="7:30 AM",Exittime="5:30PM"},
new {Name="B",Entrytime="10:30 AM",Exittime="2:30PM"},
new {Name="A",Entrytime="5:30 AM",Exittime="3:30PM"},
new {Name="B",Entrytime="11:30 AM",Exittime="4:30PM"},
new {Name="A",Entrytime="8:30 AM",Exittime="7:30PM"},
new {Name="C",Entrytime="9:30 AM",Exittime="1:30PM"},
new {Name="C",Entrytime="10:30 AM",Exittime="9:30PM"}};

var result=list.GroupBy(x=>x.Name)
    .Select(x=>new {Name=x.Key,
            Entrytime=x.Min(m=>DateTime.Parse(m.Entrytime)).ToString("h:mm tt"),
            Exittime=x.Max(m=>DateTime.Parse(m.Exittime)).ToString("h:mm tt")});

result.Dump();  

下面是一个LinqPad查询，显示了当Entrytime和Exittime是字符串而不是datetime时，如何在IEnumerable上执行此操作：

var list= new[]{
new {Name="A",Entrytime="10:30 AM",Exittime="6:30PM"},
new {Name="A",Entrytime="7:30 AM",Exittime="5:30PM"},
new {Name="B",Entrytime="10:30 AM",Exittime="2:30PM"},
new {Name="A",Entrytime="5:30 AM",Exittime="3:30PM"},
new {Name="B",Entrytime="11:30 AM",Exittime="4:30PM"},
new {Name="A",Entrytime="8:30 AM",Exittime="7:30PM"},
new {Name="C",Entrytime="9:30 AM",Exittime="1:30PM"},
new {Name="C",Entrytime="10:30 AM",Exittime="9:30PM"}};

var result=list.GroupBy(x=>x.Name)
    .Select(x=>new {Name=x.Key,
            Entrytime=x.Min(m=>DateTime.Parse(m.Entrytime)).ToString("h:mm tt"),
            Exittime=x.Max(m=>DateTime.Parse(m.Exittime)).ToString("h:mm tt")});

result.Dump();  

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对不起，我不应该假设进出时间是日期时间。我已经更新了答案。对不起，我不应该假设Entrytime和Exittime是DateTime。我已经更新了答案。