C # Extending the MapReduce method

MapReduce method Body:

1  Public StaticIdictionary<tkey, tresult> mapreduce<tinput, TKey, TValue, tresult> ( ThisIenumerable<tinput>Inputlist,2Func<tinput, Keyvalueclass<tkey, tvalue>> map, Func<tkey, Ienumerable<tvalue>, TResult>reduce)3         {4             ObjectLocker =New Object();5Concurrentdictionary<tkey, tresult> result =NewConcurrentdictionary<tkey, tresult>();6             //Save the map results7Concurrentdictionary<tkey, concurrentbag<tvalue>> mapdic =NewConcurrentdictionary<tkey, concurrentbag<tvalue>>();8             //Parallel Map9Parallel.ForEach (Inputlist, (T, p, s) = =Ten             { One                 varPair =map (t); A                 if(Pair! =NULL) -                 { -                     //lock to prevent concurrent operations list causes data loss the                     Lock(Locker) -                     { -                         //put the matching results into the dictionary in the result set -concurrentbag<tvalue> list =NULL; +                         if(Mapdic.containskey (pair). Key)) -                         { +List =Mapdic[pair. Key]; A                         } at                         Else -                         { -List =NewConcurrentbag<tvalue>(); -Mapdic[pair. Key] =list; -                         } - list. ADD (pair. Value); in                     } -                 } to             }); +  -             //Parallel Reduce theParallel.ForEach (Mapdic.keys, (T, p, s) = = *             { $RESULT[T] =reduce (t, mapdic[t]);Panax Notoginseng             }); -             returnresult; the}

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Keyvalueclass definition:

1  Public classKeyvalueclass<k, v>2     {3          PublicKeyvalueclass (K key, V value)4         {5Key =key;6Value =value;7         }8 9          PublicKeyvalueclass ()Ten         { One  A         } -  -          PublicK Key {Get;Set; } the  -          PublicV Value {Get;Set; } -}

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Console test:

1List<testclass> Listtestclass =NewList<testclass>();2Listtestclass.add (NewTestClass {a ="a", G =1 });3Listtestclass.add (NewTestClass {a ="b", G =3 });4Listtestclass.add (NewTestClass {a ="C", G =4 });5Listtestclass.add (NewTestClass {a ="D", G =2 });6Listtestclass.add (NewTestClass {a ="e", G =1 });7Listtestclass.add (NewTestClass {a ="F", G =2 });8Listtestclass.add (NewTestClass {a ="g", G =5 });9Listtestclass.add (NewTestClass {a ="h", G =6 });Tenidictionary<int,string> dic = listtestclass.mapreduce (t = One             { A                 if(T.g <5) -                 { -                     return Newkeyvalueclass<int,string>(T.G, t.a); the                 } -                 return NULL; -}, (key, values) = -            { +                return string. Join (",", values); -});

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TestClass definition:

1  Public classTestClass2     {3          Public stringAGet;Set; }4          Public stringD =Get;Set; }5 6          Public stringb =Get;Set; }7 8         //Public DateTime F {get; set;}9 Ten          Public intG {Get;Set; } One  A          PublicList<testclass> Test {Get;Set; } -  -          Publicdictionary<string,string> DIC {Get;Set; } the}

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Results:

1:a,e

2:d,f

3:b

4:c

C # Extending the MapReduce method