c# - linq query group by in a list of strings -

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this question has answer here:

i new linq query c#. have list of strings , new list or delete double strings. 

list<string> zipcodes = new list<string>(); zipcodes.add("1234"); zipcodes.add("1234"); zipcodes.add("1234"); zipcodes.add("4321"); zipcodes.add("4321");  list<string> groupbyzipcodes = (from zip in zipcodes group zip zip newgroup select newgroup.tolist());

cannot implicitly convert type 'system.collection.generic.ienumarable<system.collections.generic.list<string>' 'system.collections.generic.list<string>. explicit conversion exists (are missing cast?)

you can use distinct keyword in linq:

var dedupedlist = zipcodes.distinct().tolist();

for more see https://msdn.microsoft.com/en-us/library/vstudio/bb348436(v=vs.100).aspx


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