Export MySQL Database to EXCEL in c#.net - c#

I am using c#.net web application where i am using MySQL DB, my requirement is i want to export table data as in Excel format. please tell me how it is possible

The easiest way would be to render your data to a (html) table in plain text format. Excel loads such tables and even allows some basic and advanced configurations in css styles.
However, the other options presented here are more stable and of course recommended. But for a quick and dirty hack, a plain html table will do the trick as well.

CSV (comma separated values) are common format for Excel. It is, probably, the easiest way to export data. And very portable :)

Depending on what u really need i don't know for sure, why do u want to export table data into a Excel format? I would use SSIS with as source a odbc connection and as destination an excel connection. U'll only need to have sql server to execute the SSIS package, but will work for MySQL as source. U can execute that SSIS package in runtime behind the HttpPOST and return the uri to the excel document or something like that.
PS: This might be an elephant for your solution, as i said: depending on what u really need :)

C#.NET can access MySQL data with ADO.NET: so you can use DataReader or DataTable as well. Remember to use the correct SqlClient. Create and save a flat .csv file with the extracted data.

I am using ExcelPackagePlus for that purpose (only xlsx !), here is a method that exports DataTable to xlsx :
public static MemoryStream DataSetToExcelXlsx(DataTable table, string sheetName)
{
MemoryStream Result = new MemoryStream();
ExcelPackage pack = new ExcelPackage();
ExcelWorksheet ws = pack.Workbook.Worksheets.Add(sheetName);
int col = 1;
int row = 1;
foreach (DataRow rw in table.Rows)
{
foreach (DataColumn cl in table.Columns)
{
if (rw[cl.ColumnName] != DBNull.Value)
ws.Cells[row, col].Value = rw[cl.ColumnName].ToString();
col++;
}
row++;
col = 1;
}
pack.SaveAs(Result);
return Result;
}

Related

Parsing excel sheet - cell by cell

I would like to see your help on how to parse an excel file in mvc c# but, accessing its cell address like:
var a = Excel_cell{A1:B1}
model.a = a
I've looked to various plugin like excelfilereader, epplus and also javascript libraries like sheetjs and alike but, they do the same where they parse the whole file with the layout of a table...
My excel file is quite complicated because it has no headers and its data is on the right side.
EG:
I apologize if I put an image here...
My requirement is read an excel template, and save its data to the database.. I dont need to send the file to server because it will not be beneficial in the long run
Im hoping you could help me... An idea how to accomplish this would be really help.
You can try by using Spire.XLS, It's a good library that helps you read and write (this one only with a license) excel files and some other formats, it's easy to use and intuitive, for example this would be the code to get an excel file and read some cells:
//Create a variable to access the excel file
Workbook yourFile = new Workbook();
Stream stream = new MemoryStream(FilePath);
//Load the excel file into the variable
workbook.LoadFromStream(stream);
//Select the worksheet you want to take values from
var firstSheet = workbook.Worksheets.Where(x => x.Name == "Name of the sheet").First() as Worksheet;
string value = firstsheet.Range[A1].Text;
So with this code you have populated a variable with the excel file, a variable with a specific sheet (for example the first one), and then you save the text value of a specific cell of your choice in another variable, let me know if I got it right
EDIT: This is their site and this is the nuget gallery

How to merge csv and excel?

I am trying to build simple program that does my weekly job.
Everytime I receive csv file, I maintain excel file.
My csv is like below:
key_code,eng_name,...so on
000001,some name,...so on
My excel is like below:
Some text are written on A1-G4
No column hearders written
Data is from 5th row
Each row has data from B-G(1st row B5-G5, 2nd row B6-G6)
If key_code in csv does not exist in excel, I add.
If key_code in csv does exist in excel, I update the rest columns.
If key_code in excel does not exist in csv, I delete the row.
Can anyone tell me any easy way or steps to get this done?
I am very confusing about what to use to update excel file among OleDb, Interop.Excel, epplus, spire.xls, etc.
And in which class do I have to store csv data and excel data to compare.
For reading CSV you can use ChoETL reader, this is one of the best CSV readers I have ever used.
The tricky part is to how to write Excel file and choosing the right tool, amongst the tools you have mentioned EPPlus is best because
Excel.Interop needs Excel(MS Office) to be installed on production machine which can create licencing issues
To use OleDB you need some nitty gritty to use it a better way
EPPlus provides some abstraction which makes it easy to manipulate the excel files
using (var p = new ExcelPackage())
{
//A workbook must have at least on cell, so lets add one...
var ws=p.Workbook.Worksheets.Add("MySheet");
//To set values in the spreadsheet use the Cells indexer.
ws.Cells["A1"].Value = "This is cell A1";
//Save the new workbook. We haven't specified the filename so use the Save as method.
p.SaveAs(new FileInfo(#"c:\workbooks\myworkbook.xlsx"));
}
This is very simple example given on the github page to write, please use it and post any specific issues
If key_code in csv does not exist in excel, I add.
If key_code in csv does exist in excel, I update the rest columns.
If key_code in excel does not exist in csv, I delete the row.
As my understanding of the rules above, you simply delete the old excel file and create a new file from the data in the CSV file.
You can use R to do this very easily:
#Install package 'writexl' if you didn't, by install.packages("writexl")
library(writexl)
#File excel
fn <- "file.xlsx"
#Check its existence
if (file.exists(fn))
#Delete file if it exists
file.remove(fn)
#Read the csv file to a data frame
df <- read.csv("C:/newfile.csv")
#Write the data frame to excel file. Change col_names = TRUE if you want the headers.
write_xlsx(
df,
path = "file.xlsx",
col_names = FALSE
)

Search text in particular column and retrieve data from another column in excel using C#

I have an Excel file of 20 columns and there are about 150 records. I need to search for a particular string in a particular column with header "DESCRIPTION"(usually column b). The search string and column header values come from an INI File. After the search is found, I need to copy the value in column J (again from INI file) to the output file.
I am new to C#. Can somebody help me here. I tried Range.Find but I got confused.
Usually OLEDB with SQL like statements can be used to retrieve specific column or row data. Please go throgh following solutions:
http://www.c-sharpcorner.com/UploadFile/6b8651/read-excel-file-in-windows-application-using-C-Sharp/
https://www.codeproject.com/articles/1088970/read-write-excel-file-with-oledb-in-csharp-without
Hope this will give you some idea. But try to show some of your code so that members can have the better understanding of your approach. Thanks
Apart from Oledb connection you can also use ClosedXML. ClosedXML is a wrapper around OpenXML that allows you to easily work with .XLSX files.
https://github.com/ClosedXML/ClosedXML.
You can look at the documentation that'll help you understand how to search for text.
If you want to search .XLS files, then you can use the Microsoft Excel Interoperability libraries. These libraries cannot be used in a web app, are slower than ClosedXML but they support all kinds of Excel files.
You can use free version of GemBox.Spreadsheet to search for a text in both XLS and XLSX file formats. Also regarding the INI file, you can use MadMilkman.Ini.
Here is an example that you could try:
// Load INI file.
IniFile ini = new IniFile();
ini.Load("Sample.ini");
// Get INI values.
string header = ini.Sections["SampleSection"].Keys["ColumnHeaderValue"].Value;
string search = ini.Sections["SampleSection"].Keys["SearchTextValue"].Value;
string j = ini.Sections["SampleSection"].Keys["JColumnValue"].Value;
// Load XLSX file.
ExcelFile excel = ExcelFile.Load("Sample.xlsx");
ExcelWorksheet sheet = excel.Worksheets[0];
// Find column header value in first row.
ExcelColumn searchColumn = sheet.Rows[0].Cells
.First(cell => cell.ValueType == CellValueType.String && cell.StringValue == header)
.Column;
// Find search value in column.
int r, c;
searchColumn.Cells.FindText(search, false, false, out r, out c);
ExcelCell searchCell = sheet.Cells[r, c];
// Get cell from column "J" that is in the same row as cell that has search text.
ExcelCell jCell = sheet.Cells[r, ExcelColumnCollection.ColumnNameToIndex("J")];
// Set cell value.
jCell.Value = j;
// Save XLSX file.
excel.Save("Sample.xlsx");

How to create an excel spreadsheet using a dataset with Npoi

I am completely new to Npoi and I am struggling trying to find some information on how to create a basic spreadsheet from a DataSet.
I have a DataSet being returned that will only ever contain one table I am trying to get the columns and values from these columns into an dynamically generated excel file that I can allow users to download.
So far I have been able to create the workbook and sheet but I can't figure out how to properly populate sheet using the Npoi.dll
My code for creating the workbook (so far) is as follows:
private void CreateWorkbook(DataSet ds)
{
var table = ds.Tables[0];
var workbook = new HSSFWorkbook();
var sheet = workbook.CreateSheet();
foreach (DataColumn col in table.Columns)
{
//seems like I should create the columns for the sheet here
foreach (DataRow row in table.Rows)
{
sheet.CreateRow(); //then populate each column with the approriate data
}
}
}
In addition, and I may be missing something but where is all the documentation Npoi on codeplex mentions, I cannot find anything relevant for Mvc apps dynamically creating a sheet and returning it to the client? What I am trying to accomplish is to create create the file and pass it to the client without storing it on the server.
I'm sure this is basic but I can't figure out where to look for information. I'd appreciate any suggestions.
-cheers
A couple links that got me started:
How to read in XLSX data for editing with NPOI
Creating Excel spreadsheets .XLS and .XLSX in C#
And finally at quick overview of basic functions from the POI documentation like reading a named range, collapsing rows, etc. As NPOI is a close match to POI the guide is fairly effective.
Busy Developers' Guide to HSSF and XSSF Features

How can I export very large amount of data to excel

I'm currently using EPPlus to export data to excel. It works admirably for small amount of data. But it consume a lots of memory for large amount of data to export.
I've briefly take a look at OOXML and/or the Microsoft Open XML SDK 2.5. I'm not sure I can use it to export data to Excel?
There is also third party provider libraries.
I wonder what solution could do the job properly of exporting very large amount of data in good performance and not taking to much spaces (ideally less than 3x the amount of data to export) ?
Update: some extra requirements...
I need to be able to export "color" information (that exclude CSV) and I would like something easy to manage like EPPlus library (exclude the XML format itself). I found another thread and they recommend Aspose or SpreadsheetGear which I'm trying. I put first answer as ok. Thanks to all.
Update 2016-02-16 Just as information... We now use SpreadSheetGear and we love it. We required support once and it was awesome.
Thanks
EPPlus to export data to excel. It works admirably for small amount of data. But it consume a lots of memory for large amount of data to export.
A few years ago, I wrote a C# library to export data to Excel using the OpenXML library, and I faced the same situation.
It worked fine until you started to have about 30k+ rows, at which point, the libraries would be trying to cache all of your data... and it'd run out of memory.
However, I fixed the problem by using the OpenXmlWriter class. This writes the data directly into the Excel file (without caching it first) and is much more memory efficient.
And, as you'll see, the library is incredibly easy to use, just call one CreateExcelDocument function, and pass it a DataSet, DataTable or List<>:
// Step 1: Create a DataSet, and put some sample data in it
DataSet ds = CreateSampleData();
// Step 2: Create the Excel .xlsx file
try
{
string excelFilename = "C:\\Sample.xlsx";
CreateExcelFile.CreateExcelDocument(ds, excelFilename);
}
catch (Exception ex)
{
MessageBox.Show("Couldn't create Excel file.\r\nException: " + ex.Message);
return;
}
You can download the full source code for C# and VB.Net from here:
Mike's Export to Excel
Good luck !
If your requirements are simple enough, you can just use CSV.
If you need more detail, look into SpreadsheetML. It's an XML schema that you can use to create a text document that Excel can open natively. It supports formulas, multiple worksheets per workbook, formatting, etc.
I second using CSV but note that Excel has limits to the number of rows and columns in a worksheet as described here:
http://office.microsoft.com/en-us/excel-help/excel-specifications-and-limits-HP010342495.aspx
specifically:
Worksheet size 1,048,576 rows by 16,384 columns
This is for Excel 2010. Keep these limits in mind when working with very large amounts of data.
As an alternative you can use my SwiftExcel library. It was design for high volume Excel output that writes data directly to the file with no memory impact.
Here is a sample of usage:
using (var ew = new ExcelWriter("C:\\temp\\test.xlsx"))
{
for (var row = 1; row <= 100; row++)
{
for (var col = 1; col <= 10; col++)
{
ew.Write($"row:{row}-col:{col}", col, row);
}
}
}

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