Export Data from Listview to Excel

private void Export2Excel()
        {
            try
            {                
                //lvPDF is nothing but the listview control name
                string[] st = new string[lvPDF.Columns.Count];
                DirectoryInfo di = new DirectoryInfo(@"c:\PDFExtraction\");
                if (di.Exists == false)
                    di.Create();
                StreamWriter sw = new StreamWriter(@"c:\PDFExtraction\" + txtBookName.Text.Trim() + ".xls", false);
                sw.AutoFlush = true;
                for (int col = 0; col < lvPDF.Columns.Count; col++)
                {
                    sw.Write("\t" + lvPDF.Columns[col].Text.ToString());                    
                }
                
                int rowIndex = 1;
                int row = 0;
                string st1 = "";                
                for (row = 0; row < lvPDF.Items.Count; row++)
                {
                    if (rowIndex <= lvPDF.Items.Count)
                        rowIndex++;
                    st1 = "\n";
                    for (int col = 0; col < lvPDF.Columns.Count; col++)
                    {
                        st1 = st1 + "\t" + "'" + lvPDF.Items[row].SubItems[col].Text.ToString();                        
                    }
                    sw.WriteLine(st1);
                }
                sw.Close();
                FileInfo fil = new FileInfo(@"c:\PDFExtraction\" + txtBookName.Text.Trim() + ".xls");
                if (fil.Exists == true)
                    MessageBox.Show("Process Completed", "Export to Excel", MessageBoxButtons.OK, MessageBoxIcon.Information);
            }
            catch (Exception ex)
            {
            }
        }
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