I think you need to consider splitting this
public DataTable create(string a)
{
DataTable dt = new DataTable();
dt.Columns.Add("Saheler",typeof(String));
DataRow row = dt.NewRow();
row[0] = a;
dt.Rows.Add(row);
}
Into Something like
public DataTable create(string a)
{
DataTable dt = new DataTable();
dt.Columns.Add("Saheler",typeof(String));
return dt;
}
public AddRowToDT(ref Datatable dt, String Parameter)
{
DataRow row = dt.NewRow();
row[0] = Parameter;
dt.Rows.Add(row);
}
Given your description of what you're trying to do ...
If you want to elaborate further, and be a bit more specific, you might get a better answer