Trying to create a new .xlsx file using NPOI and write to it

Question

Edit:

I am trying to write a small console application that will read rows from an Excel spreadsheet, parse rows and write field data to a new excel file. I am using .NET and the NPOI library. Finally, after many searches, I found the Java documentation for the POI on the apache site. Here is my updated code with new bugs.

This actually creates a readable file, except that it only writes text to the third column.

public static void TransferXLToTable() { DataTable dt = new DataTable(); dt.Columns.Add("City", typeof(string)); dt.Columns.Add("State", typeof(string)); dt.Columns.Add("Zip", typeof(string)); using (FileStream stream = new FileStream(OpenFile(), FileMode.Open, FileAccess.Read)) { IWorkbook wb = new XSSFWorkbook(stream); ISheet sheet = wb.GetSheet("Sheet1"); string holder; int i = 0; do { DataRow dr = dt.NewRow(); IRow row = sheet.GetRow(i); try { holder = row.GetCell(0, MissingCellPolicy.CREATE_NULL_AS_BLANK).ToString(); } catch (Exception) { break; } string city = holder.Substring(0, holder.IndexOf(',')); string state = holder.Substring(holder.IndexOf(',') + 2, 2); string zip = holder.Substring(holder.IndexOf(',') + 5, 5); dr[0] = city; dr[1] = state; dr[2] = zip; dt.Rows.Add(dr); i++; } while (!String.IsNullOrEmpty(holder)); } using (FileStream stream = new FileStream(@"C:\Working\FieldedAddresses.xlsx", FileMode.Create, FileAccess.Write)) { IWorkbook wb = new XSSFWorkbook(); ISheet sheet = wb.CreateSheet("Sheet1"); ICreationHelper cH = wb.GetCreationHelper(); for (int i = 0; i < dt.Rows.Count; i++) { for (int j = 0; j < 3; j++) { IRow row = sheet.CreateRow(i); ICell cell = row.CreateCell(j); cell.SetCellValue(cH.CreateRichTextString(dt.Rows[i].ItemArray[j].ToString())); } } wb.Write(stream); } } 

Answer 1

I understood what happened. Actually it was a very simple mistake, I created a new line in the inner majority of loops when I needed to create a line in the outer loop. We hope that the working code in the answer will be useful for everyone who needs a starting point with NPOI.

This site is a great resource for anyone who ships with a POI or NPOI.

http://poi.apache.org/spreadsheet/quick-guide.html#NewWorkbook

Here is the working code.

  public static void TransferXLToTable() { DataTable dt = new DataTable(); dt.Columns.Add("City", typeof(string)); dt.Columns.Add("State", typeof(string)); dt.Columns.Add("Zip", typeof(string)); using (FileStream stream = new FileStream(OpenFile(), FileMode.Open, FileAccess.Read)) { IWorkbook wb = new XSSFWorkbook(stream); ISheet sheet = wb.GetSheet("Sheet1"); string holder; int i = 0; do { DataRow dr = dt.NewRow(); IRow row = sheet.GetRow(i); try { holder = row.GetCell(0, MissingCellPolicy.CREATE_NULL_AS_BLANK).ToString(); } catch (Exception) { break; } string city = holder.Substring(0, holder.IndexOf(',')); string state = holder.Substring(holder.IndexOf(',') + 2, 2); string zip = holder.Substring(holder.IndexOf(',') + 5, 5); dr[0] = city; dr[1] = state; dr[2] = zip; dt.Rows.Add(dr); i++; } while (!String.IsNullOrEmpty(holder)); } using (FileStream stream = new FileStream(@"C:\Working\FieldedAddresses.xlsx", FileMode.Create, FileAccess.Write)) { IWorkbook wb = new XSSFWorkbook(); ISheet sheet = wb.CreateSheet("Sheet1"); ICreationHelper cH = wb.GetCreationHelper(); for (int i = 0; i < dt.Rows.Count; i++) { IRow row = sheet.CreateRow(i); for (int j = 0; j < 3; j++) { ICell cell = row.CreateCell(j); cell.SetCellValue(cH.CreateRichTextString(dt.Rows[i].ItemArray[j].ToString())); } } wb.Write(stream); } }