c# - How do you create nested groups with linq via lambda/method expressions -

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is possible? example, how rewrite working code below lambda expression?

public void querynestedgroups() {     var querynestedgroups =         student in students         group student student.year newgroup1         newgroup2 in             (from student in newgroup1             group student student.lastname)         group newgroup2 newgroup1.key; }  // 3 nested foreach loops required iterate   // on elements of grouped group. hover mouse   // cursor on iteration variables see actual type.  foreach (var outergroup in querynestedgroups) {     console.writeline("dataclass.student level = {0}", outergroup.key);     foreach (var innergroup in outergroup)     {         console.writeline("\tnames begin with: {0}", innergroup.key);         foreach (var innergroupelement in innergroup)         {             console.writeline("\t\t{0} {1}", innergroupelement.lastname, innergroupelement.firstname);         }     } } 

var names = myclass1list     .selectmany(c1 => c1.class2list.where(c2 => c2.name == "something"))     .selectmany(c2 => c2.class3list.select(c3 => c3.name));  var names = myclass1list     .selectmany(c1 => c1.class2list         .where(c2 => c2.name == "something")         .selectmany(c2 => c2.class3list             .select(c3 => c3.name)));

see more: linq on list lot of nested list


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