Add a range of items to the beginning of a list?

Question

The method List<T>.AddRange(IEnumerable<T>) adds a collection of items to the end of the list:

myList.AddRange(moreItems); // Adds moreItems to the end of myList

What is the best way to add a collection of items (as some IEnumerable<T>) to the beginning of the list?

Which ways have you tried? And what makes you think there's something better than that? — O. R. Mapper, Dec 05 '12 at 11:00
One glance at the available methods list would answer that question... — Ivan Golović, Dec 05 '12 at 11:02

score 52 · Accepted Answer · answered Dec 05 '12 at 11:00

52

Use InsertRange method:

 myList.InsertRange(0, moreItems);

answered Dec 05 '12 at 11:00

Sergey Berezovskiy

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score 4 · Answer 2 · answered Dec 05 '12 at 11:01

4

Use InsertRange method:

 List<T>.InsertRange(0, yourcollection);

Also look at Insert method which you can add an element in your list with specific index.

Inserts an element into the List at the specified index.

List<T>.Insert(0, T);

answered Dec 05 '12 at 11:01

Soner Gönül

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Prabhanjan Kumar Mahapatra · Answer 3 · 2012-12-05T12:06:45.167

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List<String> listA=new List<String>{"A","B","C"};
List<String> listB=new List<String>{"p","Q","R"};

listA.InsertRange(0, listB);

Here suppose we have 2 list of string... then using the InsertRange method we can pass the starting index where we want to insert/push the new range(listB) to the existing range(listA)

Hope this clears the code.

edited Dec 05 '12 at 12:06

answered Dec 05 '12 at 11:08

Prabhanjan Kumar Mahapatra

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Rather than only post a block of code, please *explain* why this code solves the problem posed. Without an explanation, this is not an answer. – Martijn Pieters Dec 05 '12 at 11:24

score 1 · Answer 4 · answered Dec 05 '12 at 11:00

1

Please try List<T>.InsertRange(0, IEnumerable<T>)

answered Dec 05 '12 at 11:00

petro.sidlovskyy

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some explanation will help this answer – dove Dec 05 '12 at 11:19

Add a range of items to the beginning of a list?

4 Answers4