DataSelector

gistfile1.cs

// DataSelector
// description: This class loops through all merge blocks in a given template to check
// for sort keywords. The given referenced DataSet will be sorted.
//
// Parameters: dataSet of type DataSet, template as a byte[] array in the InternalUnicodeFormat
public class DataSelector
{
    public byte[] Template { get; set; }

    public DataSelector(DataSet dataSet, byte[] template)
    {
        // use a temporary ServerTextControl instance to recognize blocks with
        // the sorting keyword 'ORDERBY'
        using (TXTextControl.ServerTextControl tx =
            new TXTextControl.ServerTextControl())
        {
            tx.Create();
            // load the template
            tx.Load(template, TXTextControl.BinaryStreamType.InternalUnicodeFormat);

            // create a list of merge blocks
            List<MergeBlock> lMergeBlocks = MergeBlock.GetMergeBlocks(MergeBlock.GetBlockMarkersOrdered(tx), tx);

            // loop through all merge blocks to check whether they
            // have a sorting parameter
            foreach (MergeBlock mergeBlock in lMergeBlocks)
            {
                string sBlockName = mergeBlock.StartMarker.TargetName;

                // check for the unique sorting parameter
                if (sBlockName.ToUpper().Contains("ORDERBY") == false)
                    continue;

                // create a new SortedBlock object to store parameter
                SortedBlock block = new SortedBlock(sBlockName);

                // remove the sorting parameter from the block name
                // so that MailMerge can find the matching data in the data source
                mergeBlock.StartMarker.TargetName = block.Name;
                mergeBlock.EndMarker.TargetName = "BlockEnd_" + mergeBlock.Name;

                if (dataSet.Tables.Contains(mergeBlock.Name) == false)
                    continue;

                // get all DataRows using LINQ
                var query = from product in dataSet.Tables[mergeBlock.Name].AsEnumerable()
                            select product;

                // create a new DataTable with the sorted DataRows
                DataTable dtBoundTable = (block.SortType == SortType.ASC) ?
                    query.OrderBy(product => product.Field<String>(block.ColumnName)).CopyToDataTable() :
                    query.OrderByDescending(product => product.Field<String>(block.ColumnName)).CopyToDataTable();

                // remove original rows and replace with sorted rows
                dataSet.Tables[mergeBlock.Name].Rows.Clear();
                dataSet.Tables[mergeBlock.Name].Merge(dtBoundTable);

                dtBoundTable.Dispose();
            }

            // save the template
            byte[] data = null;
            tx.Save(out data, TXTextControl.BinaryStreamType.InternalUnicodeFormat);
            this.Template = data;
        }
    }
}