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Good Morning ALL

I have an Arralist for example
<br />1<br />2<br />3<br />4<br />5<br />2<br />4<br />3

Now i need to Find Duplicates in this array list. how can i get the Duplicated

Thank you


ArrayList is too old and try to avoid unless you are on .NET 1.1.

Method 1
list.Sort();<br />int i = 0;<br />while (i < list.Count - 1)<br />{<br />   if ((int)list[i] == (int)list[i + 1])<br />        list.RemoveAt(i);<br />   else<br />        ++i;<br />}
Method 2
ArrayList target = new ArrayList(list.ToArray().Distinct().ToArray());
This works only when you have System.Linq namespace imported.

If you use .NET 3.5, use HashSet(T) class. It will not allow duplicate entries to be created. For .NET 2.0 or later, use List(T) other than ArrayList.


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You should take "C#" out of your sig until you learn it.

This has been asked/answered at least twice before. It's homework, isn't it?

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