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Generic Extension Method Problem

Posted on 2010-09-14
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Last Modified: 2012-05-10
I'm trying to extend a wrapper of generic objects ('Retreival' in the example below) to output as a generic list, but I can't get it to work. The generic identifiers aren't recognized?
public static class Exts
    {
        public static List<T> ToList(this  Retrieval<T> lstToUse)
        {
            List<T> lstRet = new List<T>();
            foreach(T item   in  lstToUse.Results<T>)
            {
                lstRet.Add(item);
            }
            return lstRet;
        }
    }
0
Comment
Question by:Silas2
  • 2
  • 2
5 Comments
 
LVL 29

Expert Comment

by:Gautham Janardhan
ID: 33671248
are you getting any error ?
0
 
LVL 2

Expert Comment

by:SandyAgo
ID: 33671267
Hi Silas2,

I am a little unclear on what you are trying to achieve here. This might work for you. If not, can you please give some more info on the design and requirement behind this functionality?
public static class Exts
    {
        public static List<T> ToList<T>(List<T> input)
        {
            List<T> list = new List<T>();
            foreach (T item in input)
            {
                list.Add(item);
            }
            return list;
        }

    }

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LVL 29

Accepted Solution

by:
Gautham Janardhan earned 125 total points
ID: 33671310
assuming your retrival class is something like
public class Retrieval<T>
    {
        public IEnumerable<T> Results
        {
            get;
            set;
        }
    }

seethe modified code below

public static class Ext
    {
        public static List<T> ToList<T>(this  Retrieval<T> lstToUse)
        {
            List<T> lstRet = new List<T>();
            foreach (T item in lstToUse.Results)
            {
                lstRet.Add(item);
            }
            return lstRet;
        }
    }

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0
 
LVL 8

Expert Comment

by:Gururaj Badam
ID: 33671405

public static List<T> Clone<T>(this List<T> _list)
            where T : ICloneable
        {
            List<T> newList = new List<T>();

            foreach (T item in _list)
                newList.Add((T) item.Clone());

            return newList;
        }

public class Retreival : ICloneable
{
public object Clone()
        {
            return MemberwiseClone();
        }
}

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0
 
LVL 8

Assisted Solution

by:Gururaj Badam
Gururaj Badam earned 125 total points
ID: 33671411
Cloning is safer as your code just copies the reference unless you really intended that.
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