Question

Possible Duplicate:
How can I easily convert DataReader to List<T>?

I want to put the data which is coming from datareader object in a generic list. I have done like this but it doesn’t work…

I am getting cast exception error in foreach row!

 SqlDataReader pointreader = cmd2.ExecuteReader();
 var pointt = new List<int>();
 while (pointreader.Read())
 {
     foreach (int item in pointreader)
     {
        pointt.Add(item);
         if (pointt.Contains(point))
         {
             matchpoint = item;
         }
     }
 }

Answer 1

SqlDataReader cannot be accessed in the way you have described as it does not implement IEnumerable. Instead you need to access each field individually:

SqlDataReader puanoku = cmd2.ExecuteReader();
List<int> puann = new List<int>();
while (puanoku.Read())
{
    for (int i = 0; i < puanoku.FieldCount; i++)
    {
        if (puanoku.GetFieldType(i) == typeof(int))
        {
            // Do something here
        }
    }
}

If you’ve only selected one column and are certain that it is an int then you can simplify the code like so:

SqlDataReader puanoku = cmd2.ExecuteReader();
List<int> puann = new List<int>();
while (puanoku.Read())
{
    int value = puanoku.GetInt32(1);

    // Do something with the int here...
}

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