Writing and Reading excel files in C# - c#

I am writing a program that takes data from a website via selenium web driver. I am trying to create football fixture for our projects.
I am so far, I accomplished to take date and time, team names and scores from the website. Also still trying writing on txt file, but it gets little messy while writing on txt file
How do I accomplish writing on excel file, and reading?
I want to write like that
Date-Time First-Team Second-Team Score Statistics
28/07 19:00 AM AVB 2-1 Shot 13123 Pass 65465 ...
28/07 20:00 BM BVB 2-2 Shot 13123 Pass 65465 ...
28/07 20:00 CM CVB 2-3 Shot 13123 Pass 65465 ...
And this is my part of my code :
StreamWriter file = new StreamWriter(Environment.GetFolderPath(Environment.SpecialFolder.Desktop) + "\\Test" + "\\" + pathName + "\\" + subFile + "\\" + pathName + ".txt", false);
for (int k = 2; k > 1; k--)
{
//doing some stuff
}
Writing part:
for (int x = 0; x <dT.Count; x++)
{
file.Write(dateTime[x] + " " + firstTeam[x] + " "
+ secondTeam[x] + " " + firstHalf[x] + " " + secondHalf[x] + " ")
for (int i = 0; i < total_FS.Count(); i++)
{
int index = total_FS[i].Length;
if (total_FS[i][index-1].ToString() != " " && total_FS[i] != "-")
{
file.Write(total_FS[i]);
}
else
{
SpaceC++;
if (total_FS[i][index - 1].ToString() == " ")
file.Write(total_FS[i]);
}
if (SpaceC == 9)
{
file.Write("\n");
SpaceC = 0;
break;
}
}
}

There are few cool libraries that you can use to easy read and write excel files. You can reference them in your project and easily create/modify spreadsheets.
EPPlus
Very developer friendly and easy to use.
EPPlus - codeplex source
Simple tutorial
NOPI
NOPI - codeplex source
DocumentFormat.OpenXml 
It provides strongly typed classes for spreadsheet objects and seems to be fairly easy to work with.
DocumentFormat.OpenXml site
DocumentFormat.OpenXml tutorial
Open XML SDK 2.0 for Microsoft Office
Provides strongly typed classes / easy to work with.
Open XML SDK 2.0 - MSDN
ClosedXML - The easy way to OpenXML
ClosedXML makes it easier for developers to create (.xlsx, .xlsm, etc) files.
ClosedXML - repository hosted at GitHub
ClosedXML - codeplex source
SpreadsheetGear
*Paid - library to import / export Excel workbooks in ASP.NET
SpreadsheetGear site

Instead of creating XLS file, make a CSV text file that can be opened with Excel. Fields are comma separated and each line represents a record.
field11,field12
field21,field22
If a field contains inner commas, it needs to be wrapped in double quotation marks.
"field11(row1,column1)", field12
field21, field22
If a field contains double quotation marks, they need to be escaped. But you can use CsvHelper to do the job. Grab it from Nuget
PM> Install-Package CsvHelper
An example on how to use it.
using(var textWriter = new StreamWriter(#"C:\mypath\myfile.csv")
{
var writer = new CsvWriter(textWriter);
writer.Configuration.Delimiter = ",";
foreach (var item in list)
{
csv.WriteField("field11");
csv.WriteField("field12");
csv.NextRecord();
}
}
Full documentation can be found here.

Related

How to create excel file using json data using c#?

I have sample json data and want to create a xls file using that.
"{\"Id\":\"123\",\"Name\":\"DEMO\",\"Address\":\"US\",\"Team\":\"JK\"}"
Want to create a excel file stream which I will upload on azure storage using below code -
CloudFile cloudFile = cloudFileDirectory.GetFileReference("filename.xls");
cloudFile.UploadFromStream(fileStream);
output expected -
I'm able to create csv by below code -
var result = new StringBuilder();
for (int i = 0; i < table.Columns.Count; i++)
{
result.Append(table.Columns[i].ColumnName);
result.Append(i == table.Columns.Count - 1 ? "\n" : delimator);
}
foreach (DataRow row in table.Rows)
{
for (int i = 0; i < table.Columns.Count; i++)
{
result.Append(row[i].ToString());
result.Append(i == table.Columns.Count - 1 ? "\n" : delimator);
}
}
return result.ToString().TrimEnd(new char[] { '\r', '\n' });
to generate xls file from json files you should done those steps
Read file
Parse JSON file (Json.NET is the best) to your c# Class object.
Choose xls framework(using Open XML SDK or anyone which do you find)
Use structure from step 2 to fill columns and rows in xls file using framework API from step 3.
If you already have a datatable, then you can convert a data table to a spreadsheet as easy as pie using EPPLus. The code could be as simple as this:
FileInfo f = new FileInfo("filename.xlsx");
ExcelPackage package = new ExcelPackage(f);
ExcelWorksheet ws = package.Workbook.Worksheets.Add("Data");
ws.Cells["A1"].LoadFromDataTable(table, true);
If you have some special handling, for date formats and such, it might be moderately more work, but not much.
From Nuget:
Install-Package EPPlus
If you've ever worked with Excel Interop, you will love how much easier EPPlus is to work with.

WriteXML, ReadXML Issue with Table Name

I have a program where I run a query and store data in a DataTable. I then allow the user to save that DataTable.WriteXML. The problem I have is that I want to read that saved file (XML file) into another DataTable with a different name - and it does not allow it! It gives me an error "Error while loading Results Table to File: Data Table: 'ImportTable' does not match to any DataTable in Source"
Now I believe this message is telling me that the XML contains a different table name than the DataTable I am trying to ReadXML into it. I have tried setting the TableName property to blank - but that does not make any difference.
So - my question is how do others get around this issue? I am using the standard DataTable.WriteXML(filename) - and DataTable.ReadXML method calls. AND due to some design issues - I do need to have the import DataTable named differently than the one used to export the data.
Is there a different way to write out and read in the data in the DataTable that will get around this issue?
Sample code - showing the issue
In the form load - create two tables - one named Export the other Import. Create a structure for Export - and populate it with 10 records.
private void Form_Main_Load(object sender, EventArgs e)
{
ExportTable = new DataTable("Export");
ImportTable = new DataTable("Import");
ExportTable.Columns.Add("ID", Type.GetType("System.Int32"));
ExportTable.Columns.Add("Name", Type.GetType("System.String"));
ExportTable.Columns.Add("Amount", Type.GetType("System.Int32"));
// Populate the first one
DataRow workRow;
for (int i = 0; i <= 9; i++)
{
workRow = ExportTable.NewRow();
workRow[0] = i;
workRow[1] = "CustName" + i.ToString();
workRow[2] = i;
ExportTable.Rows.Add(workRow);
}
}
Then create two buttons - one for exporting the data - the other for importing the data.
private void button_Export_Click(object sender, EventArgs e)
{
ExportTable.WriteXml("c:\\Temp\\TableOut.xml");
}
private void button_Import_Click(object sender, EventArgs e)
{
ImportTable.ReadXmlSchema("c:\\Temp\\TableOut.xml");
ImportTable.ReadXml("c:\\Temp\\TableOut.xml");
}
Run the program - export the data - then click on the Import button. When you do - you will get the error - "DataTable 'Import' does not match to any DataTable in source."
Now - I realize it is because the XML has the Export table name embedded in the XML. In my case I need to import that data into a DataTable with a different name - and I am wondering how (and if) others have dealt withi this in the past? Did you manually change the name in the XML? Did you temporarily change the datatable name? OR is there another better way around this issue of trying to use the READXML method of a DataTable?
Ok - I have been playing around with this - and have a solution. Not sure it is the best (and I would appreciate any comments as to how I might do this better).
Basically what I had to do was write the XML out to a string reader - change the table name for the schema and the record elements. Both the <> and tags.
Then when I read it in - I had to do the reverse - basically read the file into a string - then change all the table names back to what I needed them to be. Then I had to write the file out to disk (temporary file) - and then use the ReadXML method to read that temp file and then delete the file.
I am not sure why the ReadXML with a string reader did not work (it seems to be a valid parameter) - but I had found a few posts that stated there were issues with the READXML method and string readers - so I simply wrote it out to file and used READXML with the file name - and it worked fine.
I hope this helps others - even if it is not the 'best' solution - maybe someone else can improve on it.
Write XML
// Write XML
StringWriter sw = new StringWriter();
ResultDT.WriteXml(sw, XmlWriteMode.WriteSchema);
string OutputXML = sw.ToString();
// now replace the Table Name
OutputXML = OutputXML.Replace("<" + ResultDT.TableName + ">", "<" + "ExportTable" + ">");
OutputXML = OutputXML.Replace("</" + ResultDT.TableName + ">", "</" + "ExportTable" + ">");
OutputXML = OutputXML.Replace("MainDataTable=\"" + ResultDT.TableName + "\"", "MainDataTable=\"" + "ExportTable" + "\"");
OutputXML = OutputXML.Replace("name=\"" + ResultDT.TableName + "\"", "name=\"" + "ExportTable" + "\"");
System.IO.File.WriteAllText(fileName, OutputXML);
Read XML
// Read XML
InputXML = System.IO.File.ReadAllText(fileName);
// now replace the Table Name
InputXML = InputXML.Replace("<" + "ExportTable" + ">", "<" + ResultTable.TableName + ">");
InputXML = InputXML.Replace("</" + "ExportTable" + ">", "</" + ResultTable.TableName + ">");
InputXML = InputXML.Replace("MainDataTable=\"" + "ExportTable" + "\"", "MainDataTable=\"" + ResultTable.TableName + "\"");
InputXML = InputXML.Replace("name=\"" + "ExportTable" + "\"", "name=\"" + ResultTable.TableName + "\"");
string TempFileName = "TempDumpFile.idt";
System.IO.File.WriteAllText(TempFileName, InputXML);
ResultTable.ReadXmlSchema(TempFileName);
ResultTable.ReadXml(TempFileName);
System.IO.File.Delete(TempFileName);

c# Getting a row in an excel file throws TargetInvocationException

I am making a program to manage different projects for a company, the idea is that you put some info and it writes it into an excel file.
The excel files are names ("FINANZAS - ") + Current Year
The idea is that it detects the current year with DateTime and if the excel file for that year doesnt exists it creates it. This is my code:
MyApp = new Excel.Application();
MyApp.Visible = false;
if (!File.Exists("FINANZAS - " + DateTime.Now.Year.ToString() + ".xlsx")) { File.Copy(rutaPlantilla, "FINANZAS ARAINCO - " + DateTime.Now.Year.ToString() + ".xlsx"); }
MyBook = MyApp.Workbooks.Open(#"C:\Users\Sebastian\Documents\Visual Studio 2015\Projects\Finanzas ARAINCO\Finanzas ARAINCO\bin\Debug\FINANZAS ARAINCO - " + DateTime.Now.Year.ToString() + ".xlsx");
MySheet = (Excel.Worksheet)MyBook.Sheets[1];
lastRow = MySheet.Cells.SpecialCells(Excel.XlCellType.xlCellTypeLastCell).Row + 1;
The problem comes when I try changing the date to test it with other years, I tried switching it to 2018 for testing but it throws me a TargetInvocationException on the last row (the one that, ironically, I use to detect the last row on excel)
I dont know if this is caused by something on the excel part of the code or if it has something to do with changing the date manually to 2018

Write tab separated csv file in c#

I am currently developing an application in C# where I need to write a tab separated CSV file from the data that it retrieves from a MySQL Database. The database retrieval works fine.
The problem that I am having is writing the file. Between each variable that I am writing I am using the \t which I thought put a tab into the csv, therefore when opening in excel each variable will be in its own cell.
However for some reason it is not doing this it just writes the whole line as one long string. Below is an example of the code that I am code that I have written:
while (reader.Read())
{
int bankID = reader.GetInt16("ban_bankID");
int userID = reader.GetInt16("ban_userID");
string bankUsername = reader.GetString("ban_username");
string accountName = reader.GetString("ban_accountName");
string accountType = reader.GetString("ban_accountType");
decimal overdraft = reader.GetDecimal("ban_overdraft");
char defaultAccount = reader.GetChar("ban_defaultAccount");
string line = bankID + "\t" + userID + "\t" + bankUsername + "\t" + accountName + "\t"
+ accountType + "\t" + overdraft + "\t" + defaultAccount + "\n";
tw.WriteLine(line);
Thanks for your help with this problem.
The format is correct, a CSV expects the file to be COMMA Separated. When saving a Tab delimited file, typically just a txt extension is used (or some people save as .tsv) etc.
If you look at the Save As options in excel the option is Text (Tab Delimited) .txt
If I open the output generated by your sample code (stubbing in the data) everything loads in to Excel 2007 as you would expect.
The problem is your encoding.
You don't show your TextWriter instantiation, but it should look something like this:
TextWriter tw = new Stream(filename, false, Encoding.ASCII);
You should use the Text Import Wizard: Data / From Text. From there you can specify your delimiter to a tab.

How do I grab the text and formatting from a PDF table with PDFBox? [duplicate]

I need to parse a PDF file which contains tabular data. I'm using PDFBox to extract the file text to parse the result (String) later. The problem is that the text extraction doesn't work as I expected for tabular data. For example, I have a file which contains a table like this (7 columns: the first two always have data, only one Complexity column has data, only one Financing column has data):
+----------------------------------------------------------------+
| AIH | Value | Complexity | Financing |
| | | Medium | High | Not applicable | MAC/Other | FAE |
+----------------------------------------------------------------+
| xyz | 12.43 | 12.34 | | | 12.34 | |
+----------------------------------------------------------------+
| abc | 1.56 | | 1.56 | | | 1.56|
+----------------------------------------------------------------+
Then I use PDFBox:
PDDocument document = PDDocument.load(pathToFile);
PDFTextStripper s = new PDFTextStripper();
String content = s.getText(document);
Those two lines of data would be extracted like this:
xyz 12.43 12.4312.43
abc 1.56 1.561.56
There are no white spaces between the last two numbers, but this is not the biggest problem. The problem is that I don't know what the last two numbers mean: Medium, High, Not applicable? MAC/Other, FAE? I don't have the relation between the numbers and their columns.
It is not required for me to use the PDFBox library, so a solution that uses another library is fine. What I want is to be able to parse the file and know what each parsed number means.
You will need to devise an algorithm to extract the data in a usable format. Regardless of which PDF library you use, you will need to do this. Characters and graphics are drawn by a series of stateful drawing operations, i.e. move to this position on the screen and draw the glyph for character 'c'.
I suggest that you extend org.apache.pdfbox.pdfviewer.PDFPageDrawer and override the strokePath method. From there you can intercept the drawing operations for horizontal and vertical line segments and use that information to determine the column and row positions for your table. Then its a simple matter of setting up text regions and determining which numbers/letters/characters are drawn in which region. Since you know the layout of the regions, you'll be able to tell which column the extracted text belongs to.
Also, the reason you may not have spaces between text that is visually separated is that very often, a space character is not drawn by the PDF. Instead the text matrix is updated and a drawing command for 'move' is issued to draw the next character and a "space width" apart from the last one.
Good luck.
You can extract text by area in PDFBox. See the ExtractByArea.java example file, in the pdfbox-examples artifact if you're using Maven. A snippet looks like
PDFTextStripperByArea stripper = new PDFTextStripperByArea();
stripper.setSortByPosition( true );
Rectangle rect = new Rectangle( 464, 59, 55, 5);
stripper.addRegion( "class1", rect );
stripper.extractRegions( page );
String string = stripper.getTextForRegion( "class1" );
The problem is getting the coordinates in the first place. I've had success extending the normal TextStripper, overriding processTextPosition(TextPosition text) and printing out the coordinates for each character and figuring out where in the document they are.
But there's a much simpler way, at least if you're on a Mac. Open the PDF in Preview, ⌘I to show the Inspector, choose the Crop tab and make sure the units are in Points, from the Tools menu choose Rectangular selection, and select the area of interest. If you select an area, the inspector will show you the coordinates, which you can round and feed into the Rectangle constructor arguments. You just need to confirm where the origin is, using the first method.
I had used many tools to extract table from pdf file but it didn't work for me.
So i have implemented my own algorithm ( its name is traprange ) to parse tabular data in pdf files.
Following are some sample pdf files and results:
Input file: sample-1.pdf, result: sample-1.html
Input file: sample-4.pdf, result: sample-4.html
Visit my project page at traprange.
It may be too late for my answer, but I think this is not that hard. You can extend the PDFTextStripper class and override the writePage() and processTextPosition(...) methods. In your case I assume that the column headers are always the same. That means that you know the x-coordinate of each column heading and you can compare the the x-coordinate of the numbers to those of the column headings. If they are close enough (you have to test to decide how close) then you can say that that number belongs to that column.
Another approach would be to intercept the "charactersByArticle" Vector after each page is written:
#Override
public void writePage() throws IOException {
super.writePage();
final Vector<List<TextPosition>> pageText = getCharactersByArticle();
//now you have all the characters on that page
//to do what you want with them
}
Knowing your columns, you can do your comparison of the x-coordinates to decide what column every number belongs to.
The reason you don't have any spaces between numbers is because you have to set the word separator string.
I hope this is useful to you or to others who might be trying similar things.
There's PDFLayoutTextStripper that was designed to keep the format of the data.
From the README:
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import org.apache.pdfbox.pdfparser.PDFParser;
import org.apache.pdfbox.pdmodel.PDDocument;
import org.apache.pdfbox.util.PDFTextStripper;
public class Test {
public static void main(String[] args) {
String string = null;
try {
PDFParser pdfParser = new PDFParser(new FileInputStream("sample.pdf"));
pdfParser.parse();
PDDocument pdDocument = new PDDocument(pdfParser.getDocument());
PDFTextStripper pdfTextStripper = new PDFLayoutTextStripper();
string = pdfTextStripper.getText(pdDocument);
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
};
System.out.println(string);
}
}
I've had decent success with parsing text files generated by the pdftotext utility (sudo apt-get install poppler-utils).
File convertPdf() throws Exception {
File pdf = new File("mypdf.pdf");
String outfile = "mytxt.txt";
String proc = "/usr/bin/pdftotext";
ProcessBuilder pb = new ProcessBuilder(proc,"-layout",pdf.getAbsolutePath(),outfile);
Process p = pb.start();
p.waitFor();
return new File(outfile);
}
Try using TabulaPDF (https://github.com/tabulapdf/tabula) . This is very good library to extract table content from the PDF file. It is very as expected.
Good luck. :)
Extracting data from PDF is bound to be fraught with problems. Are the documents created through some kind of automatic process? If so, you might consider converting the PDFs to uncompressed PostScript (try pdf2ps) and seeing if the PostScript contains some sort of regular pattern which you can exploit.
I had the same problem in reading the pdf file in which data is in tabular format. After regular parse using PDFBox each row were extracted with comma as a separator... losing the columnar position.
To resolve this I used PDFTextStripperByArea and using coordinates I extracted the data column by column for each row. This is provided that you have a fixed format pdf.
File file = new File("fileName.pdf");
PDDocument document = PDDocument.load(file);
PDFTextStripperByArea stripper = new PDFTextStripperByArea();
stripper.setSortByPosition( true );
Rectangle rect1 = new Rectangle( 50, 140, 60, 20 );
Rectangle rect2 = new Rectangle( 110, 140, 20, 20 );
stripper.addRegion( "row1column1", rect1 );
stripper.addRegion( "row1column2", rect2 );
List allPages = document.getDocumentCatalog().getAllPages();
PDPage firstPage = (PDPage)allPages.get( 2 );
stripper.extractRegions( firstPage );
System.out.println(stripper.getTextForRegion( "row1column1" ));
System.out.println(stripper.getTextForRegion( "row1column2" ));
Then row 2 and so on...
You can use PDFBox's PDFTextStripperByArea class to extract text from a specific region of a document. You can build on this by identifying the region each cell of the table. This isn't provided out of the box, but the example DrawPrintTextLocations class demonstrates how you can parse the bounding boxes of individual characters in a document (it would be great to parse bounding boxes of strings or paragraphs, but I haven't seen support in PDFBox for this - see this question). You can use this approach to group up all touching bounding boxes to identify distinct cells of a table. One way to do this is to maintain a set boxes of Rectangle2D regions and then for each parsed character find the character's bounding box as in DrawPrintTextLocations.writeString(String string, List<TextPosition> textPositions) and merge it with the existing contents.
Rectangle2D bounds = s.getBounds2D();
// Pad sides to detect almost touching boxes
Rectangle2D hitbox = bounds.getBounds2D();
final double dx = 1.0; // This value works for me, feel free to tweak (or add setter)
final double dy = 0.000; // Rows of text tend to overlap, so no need to extend
hitbox.add(bounds.getMinX() - dx , bounds.getMinY() - dy);
hitbox.add(bounds.getMaxX() + dx , bounds.getMaxY() + dy);
// Find all overlapping boxes
List<Rectangle2D> intersectList = new ArrayList<Rectangle2D>();
for(Rectangle2D box: boxes) {
if(box.intersects(hitbox)) {
intersectList.add(box);
}
}
// Combine all touching boxes and update
for(Rectangle2D box: intersectList) {
bounds.add(box);
boxes.remove(box);
}
boxes.add(bounds);
You can then pass these regions to PDFTextStripperByArea.
You can also go one further and separate out the horizontal and vertical components of these regions, and so infer regions of all the table's cells, regardless of whether then hold any content.
I have had cause to perform these steps, and eventually wrote my own PDFTableStripper class using PDFBox. I've shared my code as a gist on GitHub. The main method gives an example of how the class can be used:
try (PDDocument document = PDDocument.load(new File(args[0])))
{
final double res = 72; // PDF units are at 72 DPI
PDFTableStripper stripper = new PDFTableStripper();
stripper.setSortByPosition(true);
// Choose a region in which to extract a table (here a 6"wide, 9" high rectangle offset 1" from top left of page)
stripper.setRegion(new Rectangle(
(int) Math.round(1.0*res),
(int) Math.round(1*res),
(int) Math.round(6*res),
(int) Math.round(9.0*res)));
// Repeat for each page of PDF
for (int page = 0; page < document.getNumberOfPages(); ++page)
{
System.out.println("Page " + page);
PDPage pdPage = document.getPage(page);
stripper.extractTable(pdPage);
for(int c=0; c<stripper.getColumns(); ++c) {
System.out.println("Column " + c);
for(int r=0; r<stripper.getRows(); ++r) {
System.out.println("Row " + r);
System.out.println(stripper.getText(r, c));
}
}
}
}
It is not required for me to use the PDFBox library, so a solution that uses another library is fine
Camelot and Excalibur
You may want to try Python library Camelot, an open source library for Python. If you are not inclined to write code, you may use the web interface Excalibur created around Camelot. You "upload" the document to a localhost web server, and "download" the result from this localhost server.
Here is an example from using this python code:
import camelot
tables = camelot.read_pdf('foo.pdf', flavor="stream")
tables[0].to_csv('foo.csv')
The input is a pdf containing this table:
Sample table from the PDF-TREX set
No help is provided to camelot, it is working on its own by looking at pieces of text relative alignment. The result is returned in a csv file:
PDF table extracted from sample by camelot
"Rules" can de added to help camelot identify where are fillets in sophisticated tables:
Rule added in Excalibur. Source
GitHub:
Camelot: https://github.com/camelot-dev/camelot
Excalibur: https://github.com/camelot-dev/excalibur
The two projects are active.
Here is a comparison with other software (with test based on actual documents), Tabula, pdfplumber, pdftables, pdf-table-extract.
I want is to be able to parse the file and know what each parsed number means
You cannot do that automatically, as pdf is not semantically structured.
Book versus document
Pdf "documents" are unstructured from a semantic standpoint (it's like a notepad file), the pdf document gives instructions on where to print a text fragment, unrelated to other fragments of the same section, there is no separation between content (what to print, and whether this is a fragment of a title, a table or a footnote) and the visual representation (font, location, etc). Pdf is an extension of PostScript, which describes a Hello world! page this way:
!PS
/Courier % font
20 selectfont % size
72 500 moveto % current location to print at
(Hello world!) show % add text fragment
showpage % print all on the page
(Wikipedia).
One can imagine what a table looks like with the same instructions.
We could say html is not clearer, however there is a big difference: Html describes the content semantically (title, paragraph, list, table header, table cell, ...) and associates the css to produce a visual form, hence content is fully accessible. In this sense, html is a simplified descendant of sgml which puts constraints to allow data processing:
Markup should describe a document's structure and other attributes
rather than specify the processing that needs to be performed, because
it is less likely to conflict with future developments.
exactly the opposite of PostScript/Pdf. SGML is used in publishing. Pdf doesn't embed this semantical structure, it carries only the css-equivalent associated to plain character strings which may not be complete words or sentences. Pdf is used for closed documents and now for the so-called workflow management.
After having experimented the uncertainty and difficulty in trying to extract data from pdf, it's clear pdf is not at all a solution to preserve a document content for the future (in spite Adobe has obtained from their pairs a pdf standard).
What is actually preserved well is the printed representation, as the pdf was fully dedicated to this aspect when created. Pdf are nearly as dead as printed books.
When reusing the content matters, one must rely again on manual re-entering of data, like from a printed book (possibly trying to do some OCR on it). This is more and more true, as many pdf even prevent the use of copy-paste, introducing multiple spaces between words or produce an unordered characters gibberish when some "optimization" is done for web use.
When the content of the document, not its printed representation, is valuable, then pdf is not the correct format. Even Adobe is unable to recreate perfectly the source of a document from its pdf rendering.
So open data should never be released in pdf format, this limits their use to reading and printing (when allowed), and makes reuse harder or impossible.
ObjectExtractor oe = new ObjectExtractor(document);
SpreadsheetExtractionAlgorithm sea = new SpreadsheetExtractionAlgorithm(); // Tabula algo.
Page page = oe.extract(1); // extract only the first page
for (int y = 0; y < sea.extract(page).size(); y++) {
System.out.println("table: " + y);
Table table = sea.extract(page).get(y);
for (int i = 0; i < table.getColCount(); i++) {
for (int x = 0; x < table.getRowCount(); x++) {
System.out.println("col:" + i + "/lin:x" + x + " >>" + table.getCell(x, i).getText());
}
}
}
How about printing to image and doing OCR on that?
Sounds terribly ineffective, but it's practically the very purpose of PDF to make text inaccessible, you gotta do what you gotta do.
http://swftools.org/ these guys have a pdf2swf component. They are also able to show tables.
They are also giving the source. So you could possibly check it out.
This works fine if PDF file has "Only Rectangular table" using pdfbox 2.0.6. Won't work with any other table only Rectangular table.
import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import org.apache.pdfbox.pdmodel.PDDocument;
import org.apache.pdfbox.text.PDFTextStripper;
import org.apache.pdfbox.text.PDFTextStripperByArea;
public class PDFTableExtractor {
public static void main(String[] args) throws IOException {
ArrayList<String[]> objTableList = readParaFromPDF("C:\\sample1.pdf", 1,1,6);
//Enter Filepath, startPage, EndPage, Number of columns in Rectangular table
}
public static ArrayList<String[]> readParaFromPDF(String pdfPath, int pageNoStart, int pageNoEnd, int noOfColumnsInTable) {
ArrayList<String[]> objArrayList = new ArrayList<>();
try {
PDDocument document = PDDocument.load(new File(pdfPath));
document.getClass();
if (!document.isEncrypted()) {
PDFTextStripperByArea stripper = new PDFTextStripperByArea();
stripper.setSortByPosition(true);
PDFTextStripper tStripper = new PDFTextStripper();
tStripper.setStartPage(pageNoStart);
tStripper.setEndPage(pageNoEnd);
String pdfFileInText = tStripper.getText(document);
// split by whitespace
String Documentlines[] = pdfFileInText.split("\\r?\\n");
for (String line : Documentlines) {
String lineArr[] = line.split("\\s+");
if (lineArr.length == noOfColumnsInTable) {
for (String linedata : lineArr) {
System.out.print(linedata + " ");
}
System.out.println("");
objArrayList.add(lineArr);
}
}
}
} catch (Exception e) {
System.out.println("Exception " +e);
}
return objArrayList;
}
}
For anyone wanting to do the same thing as OP (as I do), after days of research Amazon Textract is the best option (if your volume is low free tier might be enough).
consider using PDFTableStripper.class
The class is available on git :
https://gist.github.com/beldaz/8ed6e7473bd228fcee8d4a3e4525be11#file-pdftablestripper-java-L1
I'm not familiar with PDFBox, but you could try looking at itext. Even though the homepage says PDF generation, you can also do PDF manipulation and extraction. Have a look and see if it fits your use case.
For reading content of the table from pdf file,you have to do only just convert the pdf file into a text file by using any API(I have use PdfTextExtracter.getTextFromPage() of iText) and then read that txt file by your java program..now after reading it the major task is done.. you have to filter the data of your need. you can do it by continuously using split method of String class until you find record of your intrest.. here is my code by which I have extract part of record by an PDF file and write it into a .CSV file.. Url of PDF file is..http://www.cea.nic.in/reports/monthly/generation_rep/actual/jan13/opm_02.pdf
Code:-
public static void genrateCsvMonth_Region(String pdfpath, String csvpath) {
try {
String line = null;
// Appending Header in CSV file...
BufferedWriter writer1 = new BufferedWriter(new FileWriter(csvpath,
true));
writer1.close();
// Checking whether file is empty or not..
BufferedReader br = new BufferedReader(new FileReader(csvpath));
if ((line = br.readLine()) == null) {
BufferedWriter writer = new BufferedWriter(new FileWriter(
csvpath, true));
writer.append("REGION,");
writer.append("YEAR,");
writer.append("MONTH,");
writer.append("THERMAL,");
writer.append("NUCLEAR,");
writer.append("HYDRO,");
writer.append("TOTAL\n");
writer.close();
}
// Reading the pdf file..
PdfReader reader = new PdfReader(pdfpath);
BufferedWriter writer = new BufferedWriter(new FileWriter(csvpath,
true));
// Extracting records from page into String..
String page = PdfTextExtractor.getTextFromPage(reader, 1);
// Extracting month and Year from String..
String period1[] = page.split("PEROID");
String period2[] = period1[0].split(":");
String month[] = period2[1].split("-");
String period3[] = month[1].split("ENERGY");
String year[] = period3[0].split("VIS");
// Extracting Northen region
String northen[] = page.split("NORTHEN REGION");
String nthermal1[] = northen[0].split("THERMAL");
String nthermal2[] = nthermal1[1].split(" ");
String nnuclear1[] = northen[0].split("NUCLEAR");
String nnuclear2[] = nnuclear1[1].split(" ");
String nhydro1[] = northen[0].split("HYDRO");
String nhydro2[] = nhydro1[1].split(" ");
String ntotal1[] = northen[0].split("TOTAL");
String ntotal2[] = ntotal1[1].split(" ");
// Appending filtered data into CSV file..
writer.append("NORTHEN" + ",");
writer.append(year[0] + ",");
writer.append(month[0] + ",");
writer.append(nthermal2[4] + ",");
writer.append(nnuclear2[4] + ",");
writer.append(nhydro2[4] + ",");
writer.append(ntotal2[4] + "\n");
// Extracting Western region
String western[] = page.split("WESTERN");
String wthermal1[] = western[1].split("THERMAL");
String wthermal2[] = wthermal1[1].split(" ");
String wnuclear1[] = western[1].split("NUCLEAR");
String wnuclear2[] = wnuclear1[1].split(" ");
String whydro1[] = western[1].split("HYDRO");
String whydro2[] = whydro1[1].split(" ");
String wtotal1[] = western[1].split("TOTAL");
String wtotal2[] = wtotal1[1].split(" ");
// Appending filtered data into CSV file..
writer.append("WESTERN" + ",");
writer.append(year[0] + ",");
writer.append(month[0] + ",");
writer.append(wthermal2[4] + ",");
writer.append(wnuclear2[4] + ",");
writer.append(whydro2[4] + ",");
writer.append(wtotal2[4] + "\n");
// Extracting Southern Region
String southern[] = page.split("SOUTHERN");
String sthermal1[] = southern[1].split("THERMAL");
String sthermal2[] = sthermal1[1].split(" ");
String snuclear1[] = southern[1].split("NUCLEAR");
String snuclear2[] = snuclear1[1].split(" ");
String shydro1[] = southern[1].split("HYDRO");
String shydro2[] = shydro1[1].split(" ");
String stotal1[] = southern[1].split("TOTAL");
String stotal2[] = stotal1[1].split(" ");
// Appending filtered data into CSV file..
writer.append("SOUTHERN" + ",");
writer.append(year[0] + ",");
writer.append(month[0] + ",");
writer.append(sthermal2[4] + ",");
writer.append(snuclear2[4] + ",");
writer.append(shydro2[4] + ",");
writer.append(stotal2[4] + "\n");
// Extracting eastern region
String eastern[] = page.split("EASTERN");
String ethermal1[] = eastern[1].split("THERMAL");
String ethermal2[] = ethermal1[1].split(" ");
String ehydro1[] = eastern[1].split("HYDRO");
String ehydro2[] = ehydro1[1].split(" ");
String etotal1[] = eastern[1].split("TOTAL");
String etotal2[] = etotal1[1].split(" ");
// Appending filtered data into CSV file..
writer.append("EASTERN" + ",");
writer.append(year[0] + ",");
writer.append(month[0] + ",");
writer.append(ethermal2[4] + ",");
writer.append(" " + ",");
writer.append(ehydro2[4] + ",");
writer.append(etotal2[4] + "\n");
// Extracting northernEastern region
String neestern[] = page.split("NORTH");
String nethermal1[] = neestern[2].split("THERMAL");
String nethermal2[] = nethermal1[1].split(" ");
String nehydro1[] = neestern[2].split("HYDRO");
String nehydro2[] = nehydro1[1].split(" ");
String netotal1[] = neestern[2].split("TOTAL");
String netotal2[] = netotal1[1].split(" ");
writer.append("NORTH EASTERN" + ",");
writer.append(year[0] + ",");
writer.append(month[0] + ",");
writer.append(nethermal2[4] + ",");
writer.append(" " + ",");
writer.append(nehydro2[4] + ",");
writer.append(netotal2[4] + "\n");
writer.close();
} catch (IOException ioe) {
ioe.printStackTrace();
}
}

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