Hi
I have not used late binding before but it would seem to be the solution, if only I could find a concise example!
Or may be it's not the solution but I'm sure you guys will know!
I need to fill a dropdown combbox list from a column in excel reading down to the first blank cell. the solution needs to work with excel 2003 and above some PCs never have had 2003 install only office 2010 other have been upgraded from 2003 and some are still on 2003!
I need a solution that works on all of the above.
So I'm looking into late binding is this the correct way to go? would Linq help!?
Its a clasic windows Form app using .Net 4.
I thought I would write a method that takes the file name and path and returns a list which I would then assign to the combobox.
But being new I'm not getting pass go!
Any help/examples PLEASE
It sounds like you're looking at using COM interop/automation with the Excel application installed on client machines.
If your sole requirement is to extract data from an Excel file, you'll be better off using a library that can simply read data out of the file itself, rather than launching the Excel process in the background.
It is faster, cleaner, and more testable.
I've used NPOI for .xls files (and there are certainly others), and there are LOTS of options for .xlsx files. This SO question is about creating a file, but any of the suggested libraries can of course read files as well.
The only time I'd use COM automation is to interact with a running instance of Excel.
Edit (in response to comments)
Here is a sample of getting the values of column B as strings:
using System;
using System.IO;
using NPOI.HSSF.UserModel;
using NPOI.SS.UserModel;
namespace ConsoleApplication1
{
class Program
{
static void Main(string[] args)
{
var stream = new FileStream(#"c:\my_workbook.xls", FileMode.Open);
var workbook = new HSSFWorkbook(stream);
stream.Close();
var sheet = workbook.GetSheet("My Sheet Name");
var row_enumerator = sheet.GetRowEnumerator();
while (row_enumerator.MoveNext())
{
var row = (Row)row_enumerator.Current;
var cell = row.GetCell(1); // in Excel, indexes are 1-based; in NPOI the indexes are 0-based
Console.WriteLine(cell.StringCellValue);
}
Console.ReadKey();
}
}
}
Related
I have a controller endpoint from which I want to generate a csv file and download it.
Currently I am using nuget CsvHelper and my code is like this:
var cc = new CsvConfiguration(new System.Globalization.CultureInfo("sl-SI"));
using (var ms = new MemoryStream())
{
using (var sw = new StreamWriter(stream: ms, encoding: new UTF8Encoding(true)))
{
using (var cw = new CsvWriter(sw, cc))
{
cw.WriteRecords(ListOfReports);
}// The stream gets flushed here.
return File(ms.ToArray(), "text/csv", $"{docNumber.Trim()}_{docType}.csv");
}
}
It generated csv pretty nice, but the problem was, if I opened it in Excel, whole row was in the first column and was not splitted.
I added this part:
cw.WriteField("sep=,", false);
cw.NextRecord();
Before cw.WriteRecords(ListOfReports);, which made it work in Excel, but if I open it in Notepad, there is a sep=, in my first row.
I noticed there is a difference in CultureInfo, If I set "sl-SI" it will work properly on Slovenian windows (separator will be ;), if I set "en-US" it will work on English Windows (separator ,). But what do i need to do to work on any Culture?
Does anyone has any idea how to fix this so it will work properly in Excel and any other text editor?
This is effectively the same as this SuperUser question, but it appears you want a programming-oriented solution rather than a user-oriented one.
The problem is fundamentally that Excel is really bad at dealing with CSV files, especially when taking non-US cultures into account. My suggestion would be to allow users to download a real Excel file using a library like DocumentFormat.OpenXml.
If you have two separate use cases for your downloads (i.e. some users who open the file in notepad or consume it with software that reads CSV, and others who open the file in Excel), give the users separate options to download in CSV or Excel.
I mostly write number-crunching programs using Visual Studio C# (2019) where I am simply taking input data, calculating results and displaying it. No complicated Network or Internet programming. Think first or second college level programming coarse from the early 1990's.
For inputs I was reading in data from an excel file using the following directive:
using Excel = Microsoft.Office.Interop.Excel;
This proved to be very slow when executing the program. I then learned this way of accessing an Excel file is no longer supported and has been superseded by Open XML SDK. Please see the following link to the Microsoft Dev Center page:
https://learn.microsoft.com/en-us/office/open-xml/how-to-parse-and-read-a-large-spreadsheet
For what I want to do the Document Object Model(DOM) approach seems most appropriate for the thousands of individual excel cells I want to read as input data. However, the Microsoft Dev Center is certainly not the most user-friendly resource and the code example provided for reading an Excel file using this DOM approach is writing to a console which I'm not using. I never did get my code to work.
Long and short of it is, I got my code working using the GetCellValue Method:
https://learn.microsoft.com/en-us/office/open-xml/how-to-retrieve-the-values-of-cells-in-a-spreadsheet
However, this 'GetCellValue' method is still taking way too long. I need to read in thousands or tens of thousands of Excel input data cells in seconds or fractions of seconds not 20 seconds to a minute.
I think if I had an example of the DOM method reading in Excel data to an Array Variable (instead of writing to the console) it would help. Can anyone provide an example of such code?
Below I have included my code example where I modified the DOM approach code copied from the Microsoft Office Dev Center to write values from a source Excel File to a DataGrid instead of the Console used by the Dev Center code:
C#
// The DOM approach.
// Note that the code below works only for cells that contain numeric values.
//
public void ReadExcelFileDOM(string fileName)
{
using (SpreadsheetDocument spreadsheetDocument = SpreadsheetDocument.Open(fileName, false))
{
WorkbookPart workbookPart = spreadsheetDocument.WorkbookPart;
WorksheetPart worksheetPart = workbookPart.WorksheetParts.First();
SheetData sheetData = worksheetPart.Worksheet.Elements<SheetData>().First();
DataGridView_Vessel.Rows.Clear();
DataGridView_Vessel.Refresh();
string text;
int File_Row = 0;
int File_Cell = 0;
foreach (Row r in sheetData.Elements<Row>())
{
DataGridView_Vessel.Rows.Add();
foreach (Cell c in r.Elements<Cell>())
{
if (c.CellValue == null)
{
File_Cell++;
//continue;
}
else
{
text = c.CellValue.Text;
if(File_Cell<12)
{
DataGridView_Vessel.Rows[File_Row].Cells[File_Cell].Value = text;
}
File_Cell++;
}
}
File_Row++;
}
//Console.WriteLine();
//Console.ReadKey();
}
}
I am trying to automate a Powerpoint presentation. I am using OpenXML to navigate the powerpoint presentation up to the point that I find the Excel linked to a chart. Now I want to use EPPlus to load a datatable into one of the worksheets (because EPPlus has a simple LoadFromDataTable function whereas I think I would have to write lots of code to use OpenXML).
So my problem is this.
I have a PresentationDocument in memory. And I have navigated to the particular chart that I want to manipulate via:
doc.PresentationPart.SlideParts.ElementAt(0).ChartParts.ElementAt(0)
I get the Excel part using:
var stream = chartpart.EmbeddedPackagePart.GetStream()
Then I tried:
using(var pck = new ExcelPackage(stream)) {
`do stuff;
`pck.Save();
}
and then at the end I do a doc.PresentationPart.Presentation.Save but this hasn't changed the Presentation. I can change it using OpenXML instead with:
using (var xl = Spreadsheet.Document.Open(stream, true))
{
`do stuff;
`xl.Close();
}
With everything else the same. So I guess either xl.Close() is doing stuff that pck.Save() isn't or I am using the stream incorrectly - can anyone advise?
I am developing an Excel Addin that is able to fetch data from our database.Instead of dumping the data directly , I would like to have the data presented in a nice format. I have got our local VBA expert to develop a templates for the same since there can be multiple sheets all of which can have different formats.
It is while adding the worksheet that I am stuck at.
string TemplateFileLocation = Path.GetFullPath(fileName);
if(File.Exists(fileName))
{
Worksheet newWorkSheet = (WorkSheet)Globals.ThisAddin.Aplication.Worksheets.Add(Missing.Value,Missing.Value,1,TemplateFileLocation);
}
The code crashes while it hits this location.
The Error code returned is : 0x800A03EC
I have verified that the path to the template file is correct.
Each of these templates have only one work sheet.
You can use EPPlus
using System.IO;
using System.Reflection;
using OfficeOpenXml;
//Create a stream of .xlsx file contained within my project using reflection
Stream stream = Assembly.GetExecutingAssembly().GetManifestResourceStream("EPPlusTest.templates.VendorTemplate.xlsx");
//EPPlusTest = Namespace/Project
//templates = folder
//VendorTemplate.xlsx = file
//ExcelPackage has a constructor that only requires a stream.
ExcelPackage pck = new OfficeOpenXml.ExcelPackage(stream);
I need some way to read worksheets from an Excel file, then select what it's important, and put all the Data in a Database.
It's a job for one time only. It's an old excel file with information, that have to be passed to a Database, and which will work with an application that i have developed.
I saw many examples but i am not understanding well how it works, and which way is the best to do this type of work.
My idea is to develop some application in c# that to this process.
LINQ may work and would be preferable for a relatively simple table.
A traditional approach would be to use COM Interop. Here's a Microsoft page about to work with Excel using COM interop (it is for spreadsheet creation, but the principles are the same - just use different API methods to open and read data):
http://msdn.microsoft.com/en-us/library/ms173186(v=vs.80).aspx
I strongly suggest using a linq provider to connect to excel. This should make it very easy to query for the information you are looking for. Once you have it, inserting into the database should be easy.
http://code.google.com/p/linqtoexcel/
I've used this before and it works well.
http://exceldatareader.codeplex.com/
had an example handy...
using (FileStream fileStream = File.Open(inputFilenames[0], FileMode.Open, FileAccess.Read))
{
IExcelDataReader excelReader;
if (Path.GetExtension(inputFilenames[0]) == ".xls")
excelReader = Factory.CreateReader(fileStream, ExcelFileType.Binary);
else
excelReader = Factory.CreateReader(fileStream, ExcelFileType.OpenXml);
excelReader.NextResult();
while (excelReader.Name != this.Worksheet)
excelReader.NextResult();
while (excelReader.Read())
{
if (FirstRowHasColumnNames)
{
FirstRowHasColumnNames = false;
}
else
{
//do stuff
var test = GetColumnData(excelReader, 1);
}
}
this.Save(outputFilename);
}
Read Data from Excel Worksheet in c#? I got the Exact solution here visit
http://microsoftdotnetsolutions.blogspot.in/2012/12/get-excel-sheet-data.html