>Hi All, just in the middle of a code review and I'm finding lots of methods in different classes that use the following method for populating Dictionary and List objects - I'm wondering if there is an easier / generic way using Linq ( It looks like a black art to me ) this is what I have at present
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>DataSet ds = SomeMethodThatReturnsADataSet("MyDS");
>Dictionary<string,string>  MyDictionary = new Dictionary<string,string>(StringComparer.CurrentCultureIgnoreCase);
>
>foreach(DataRow dr in ds.Tables[0].Rows)
>    MyDictionary.Add(dr["KeyName"].ToString(),dr["KeyValue"].ToString());
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>which is pretty basic and clean but , this code is scattered among dozens of classes - any thoughts very welcome

Don't think you can use Linq to directly construct the Dictionary. But, if the variables are basically the DataTable and the two Column names then you could make it more generic. Something like:

public IEnumerable<KeyValuePair<string,string>>  GetEntries(DataTable dt, string keyField, string valueField)
        {
            foreach (DataRow d in dt.AsEnumerable())
            {
                yield return new KeyValuePair<string, string>(d[keyField].ToString(), d[valueField].ToString());
            }
        }

which could then be called as:

foreach (var v in GetEntries(ds.Tables[0], "KeyName", "KeyValue"))
            {
                MyDictionary.Add(v.Key, v.Value);
            }

Not much benefit there as is but if you ever needed to do things like selectively filtering the list it could be more useful. e.g:

var v2 = from x in GetEntries(dt,"KeyName","KeyValue").Where(x=>x.Value.StartsWith("Fred")) select x ;
            foreach( KeyValuePair<string,string> xx in v2)
            {
                MyDictionary.Add(xx.Key, xx.Value);
            }