Forms Data Controls :: Sorting In Dataview?

I want to sort the string which is in the format given below15% Test;15% Sear;40% Santhosh;30% Jeeson;
The output that I am expecting is

40% Santhosh;30% Jeeson;15% Sear;15% Test;

I wrote the following code but it does not work .

string str = "15% Test;15% Sear;40% Santhosh;30% Jeeson;";
Console.WriteLine(str);
DataTable dt = new DataTable("SortBenchMark");
DataRow dr;
dt.Columns.Add("Weightings", typeof(int));
dt.Columns.Add("BenchMark", typeof(string));
string weightings = string.Empty;
string BenchMarkName = string.Empty;
foreach (object o in str.Split(';'))
{
if(o.ToString().Length > 0)
{
dr = dt.NewRow();
dr["Weightings"] = Convert.ToInt32((o.ToString().Split('%'))[0].ToString().Trim());
dr["BenchMark"] = (o.ToString().Split('%'))[1].ToString().Trim();
dt.Rows.Add(dr);
}
}
dt.AcceptChanges();
DataView dataview = new DataView(dt);
dataview.Sort = "Weightings DESC,BenchMark Asc";
string final = string.Empty;
foreach (DataRow drow in dataview.Table.Rows)
{
final += drow["Weightings"].ToString().Trim() + "% " + drow["BenchMark"].ToString().Trim() + ";";
}
Console.WriteLine(final);
Console.ReadLine();