Develop Reference

Read Data from Excel Sheet in C#, .NET

Excel Data reader read data from Excel sheet in order compare it with the UI dropdown values and see if they exists
I am trying to read data from excel sheet using below code
// methods to read data and parse the data into populate collection
using ExcelDataReader;
using System;
using System.Collections.Generic;
using System.Data;
using System.IO;
using System.Linq;
namespace GorillaUITests.PageObjects
{
public class ExcelRead
{
public static List<Datacollection> dataCol = new List<Datacollection>();
public static DataTable ExcelToDataTable(string fileName)
{
using (var stream = File.Open(fileName, FileMode.Open, FileAccess.Read))
{
using (var reader = ExcelReaderFactory.CreateReader(stream))
{
var result = reader.AsDataSet(new ExcelDataSetConfiguration()
{
UseColumnDataType = true,
ConfigureDataTable = (data) => new ExcelDataTableConfiguration()
{
UseHeaderRow = true
}
});
//Get all the Tables
DataTableCollection table = result.Tables;
//Store it in DataTable
DataTable resultTable = table["Sheet1"];
//return
return resultTable;
}
}
}
public static void PopulateInCollection(string fileName)
{
DataTable table = ExcelToDataTable(fileName);
//Iterate through the rows and columns of the Table
for (int row = 1; row <= table.Rows.Count; row++)
{
for (int col = 0; col < table.Columns.Count; col++)
{
Datacollection dtTable = new Datacollection()
{
rowNumber = row,
colName = table.Columns[col].ColumnName,
colValue = table.Rows[row - 1][col].ToString()
};
//Add all the details for each row
dataCol.Add(dtTable);
}
}
}
/// <summary>
/// Read data from Collection
/// </summary>
/// <param name="rowNumber"></param>
/// <param name="columnName"></param>
/// <returns></returns>
public static string ReadData(int rowNumber, string columnName)
{
try
{
//Retriving Data using LINQ to reduce much of iterations
string data = (from colData in dataCol
where colData.colName == columnName && colData.rowNumber == rowNumber
select colData.colValue).SingleOrDefault();
//var datas = dataCol.Where(x => x.colName == columnName && x.rowNumber == rowNumber).SingleOrDefault().colValue;
return data.ToString();
}
catch (Exception e)
{
Console.WriteLine(e.Message);
return null;
}
}
}
public class Datacollection
{
public int rowNumber { get; set; }
public string colName { get; set; }
public string colValue { get; set; }
}
}
// Test to see if we are able to read data
public void ReadDataFromExcel(string user, string pass)
{
// populate data in collection
try
{
ExcelRead.PopulateInCollection(#"C:\Users\username\Documents\GorillaUITests\GorillaUITests\Tests\Data\ReadDataTest.xlsx");
Debug.WriteLine("UserName:" + ExcelRead.ReadData(1, "UserName"));
Debug.WriteLine("Email:" + ExcelRead.ReadData(1, "Email"));
Debug.WriteLine("***********");
Debug.WriteLine("UserName:" + ExcelRead.ReadData(2, "UserName"));
Debug.WriteLine("Email:" + ExcelRead.ReadData(2, "Email"));
Debug.WriteLine("***********");
Debug.WriteLine("Username:" + ExcelRead.ReadData(2, "UserName"));
Debug.WriteLine("Email:" + ExcelRead.ReadData(2, "Email"));
Debug.WriteLine("***********");
catch (Exception e)
{
Console.WriteLine(e.Message);
}
And I see this error below
“Object reference not set to an instance of an object.”
Not sure what I am missing, Any inputs would be appreciated

Consecutively reading data from Excel in C#/NUnit test cases, returns blank data for 2nd Case

I'm trying to write a parameterized NUnit test that executes twice. Each time it runs, it references a different row in a spreadsheet and gets the username and password based on int rowNum.
class Test
{
//Run the test twice
[Test,TestCase(1),TestCase(2)]
public void T101_LoginTestSuite_Valid(int rowNum)
{
Console.WriteLine(TestContext.CurrentContext.Test.MethodName); //Test Name
Console.WriteLine("Row number "+rowNum);// Value of rowNum
ExcelDataFactory.GetTestDataSet(TestContext.CurrentContext.Test.MethodName);
//Print out the credentials
Console.WriteLine(ExcelDataFactory.ReadData(rowNum,"username"));
Console.WriteLine(ExcelDataFactory.ReadData(rowNum, "password"));
}
}
Here is the excel
The first test case gets username and password correctly.
However the second test case returns blank (If I run this individually it will work!)
Below is the ExcelDataFactory code:
class ExcelDataFactory
{
//Get data from excel
private static DataTable ExcelToDataTable(String filename, String sheetName)
{
//Open file and returns as Stream
FileStream stream = File.Open(filename, FileMode.Open, FileAccess.Read);
//CreateOpenXmlReader via ExcelReaderFactory
IExcelDataReader excelReader = ExcelReaderFactory.CreateOpenXmlReader(stream); //.xlsx
//Return as DataSet and set the frist row as column name
DataSet result = excelReader.AsDataSet(new ExcelDataSetConfiguration()
{
ConfigureDataTable = (_) => new ExcelDataTableConfiguration()
{
UseHeaderRow = true
}
});
DataTableCollection table = result.Tables;
DataTable resultTable = table[sheetName];
//Close FileStream
stream.Close();
//Return
return resultTable;
}
//Put data into a collection
static List<DataCollection> dataCollection = new List<DataCollection>();
public static void PopulateInCollection(string fileName, String sheetName)
{
DataTable table = ExcelToDataTable(fileName,sheetName);
//Iterate through the rows and columns of the Table
for(int row = 1; row <= table.Rows.Count; row++)
{
for (int column = 0; column < table.Columns.Count; column++)
{
DataCollection dataTable = new DataCollection()
{
rowNumber = row,
columnName = table.Columns[column].ColumnName,
columnValue = table.Rows[row - 1][column].ToString()
};
//Add all the details for each row
dataCollection.Add(dataTable);
}
}
}
//Find the correct excel file and sheet
public static void GetTestDataSet(String testName)
{
String[] testNameSplit = testName.Split('_');
String filePath = MyProps.Default.TestData //Add path
+ testNameSplit[1]
+ "."
+ "xlsx";
PopulateInCollection(filePath, testNameSplit[0]);
}
public static string ReadData(int rowNumber, string columnName)
{
try
{
//Retriving Data using LINQ to reduce amount of iterations
string data = (from collectionData in dataCollection
where collectionData.columnName == columnName && collectionData.rowNumber == rowNumber
select collectionData.columnValue).SingleOrDefault();
//var data = dataCollection.Where(collectionData => collectionData.columnName == columnName && collectionData.rowNumber == rowNumber).SingleOrDefault().columnValue;
return data.ToString();
}
catch (Exception e)
{
e.StackTrace.ToString();
return null;
}
}
}
class DataCollection
{
public int rowNumber { get; set; }
public string columnName { get; set; }
public string columnValue { get; set; }
}
I suspect that the ExcelDataFactory.GetTestDataSet method is called in the wrong place, but I really am stumped as to why this is happening. Any ideas would be greatly appreciated.

I did some quick changes to ExcelDataFactory class, I removed the static references and now PopulateInCollection method returns a List that is declared and initialized at the start of the class.
using ExcelDataReader;
using NUnit.Framework;
using System;
using System.Collections.Generic;
using System.Data;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace Wizuda_Selenium_Test_Automation
{
class ExcelDataFactory
{
List<DataCollection> dataCollection = new List<DataCollection>();
private static DataTable ExcelToDataTable(String filename, String sheetName)
{
//Open file and returns as Stream
FileStream stream = File.Open(filename, FileMode.Open, FileAccess.Read);
//CreateOpenXmlReader via ExcelReaderFactory
IExcelDataReader excelReader = ExcelReaderFactory.CreateOpenXmlReader(stream); //.xlsx
//Return as DataSet and set the frist row as column name
DataSet result = excelReader.AsDataSet(new ExcelDataSetConfiguration()
{
ConfigureDataTable = (_) => new ExcelDataTableConfiguration()
{
UseHeaderRow = true
}
});
DataTableCollection table = result.Tables;
DataTable resultTable = table[sheetName];
//Close FileStream
stream.Close();
//Return
return resultTable;
}
//static List<DataCollection> dataCollection = new List<DataCollection>();
public List<DataCollection> PopulateInCollection(string fileName, String sheetName)
{
dataCollection = new List<DataCollection>();
DataTable table = ExcelToDataTable(fileName,sheetName);
//Iterate through the rows and columns of the Table
for(int row = 1; row <= table.Rows.Count; row++)
{
for (int column = 0; column < table.Columns.Count; column++)
{
DataCollection dataTable = new DataCollection()
{
rowNumber = row,
columnName = table.Columns[column].ColumnName,
columnValue = table.Rows[row - 1][column].ToString()
};
//Add all the details for each row
dataCollection.Add(dataTable);
}
}
return dataCollection;
}
public string ReadData(int rowNumber, string columnName)
{
try
{
//Retriving Data using LINQ to reduce amount of iterations
string data = (from collectionData in dataCollection
where collectionData.columnName == columnName && collectionData.rowNumber == rowNumber
select collectionData.columnValue).SingleOrDefault();
//var data = dataCollection.Where(collectionData => collectionData.columnName == columnName && collectionData.rowNumber == rowNumber).SingleOrDefault().columnValue;
return data.ToString();
}
catch (Exception e)
{
e.StackTrace.ToString();
return null;
}
}
public void GetTestDataSet(String testName)
{
String[] testNameSplit = testName.Split('_');
String filePath = MyProps.Default.TestData //Add path
+ testNameSplit[1] //LoginTestSuite
+ "."
+ "xlsx"; //T101
PopulateInCollection(filePath, testNameSplit[0]);
}
}
class DataCollection
{
public int rowNumber { get; set; }
public string columnName { get; set; }
public string columnValue { get; set; }
}
}
I updated the test to create new instance of ExcelDataFactory
[Test,TestCase(1),TestCase(2)]
public void T101_LoginTestSuite_Valid(int rowNum)
{
ExcelDataFactory excelDataFactory = new ExcelDataFactory();
Console.WriteLine(TestContext.CurrentContext.Test.MethodName);
Console.WriteLine("Row number "+rowNum);
excelDataFactory.GetTestDataSet(TestContext.CurrentContext.Test.MethodName);
Console.WriteLine("username= "+ excelDataFactory.ReadData(rowNum,"username"));
Console.WriteLine("password= "+ excelDataFactory.ReadData(rowNum, "password"));
}
And now the test passes
I guess I need to go back and re-learn about the use static methods, thanks Kritner

Difficulties with C# + Excel

I have a problem.
I have an Excel File where sometimes the same customer is in 2 rows.
But not always.
Its like:
Click
Now, i want to create a DataGrid in C# which can list this in one row like:
Click
I know it would be easier to change the Excel file, but assume it wouldnt work that way(we get the file like this and we cant change it)
I know i could too just make another Excel File and make it with Excel(already did it this way, but we would need it more as C#)
Now i am at this point:
private void button2_Click(object sender, EventArgs e)
{
OpenFileDialog ofd = new OpenFileDialog() { Filter = "Excel Arbeitsmappe |*.xlsx", ValidateNames = true };
if (ofd.ShowDialog() == DialogResult.OK)
textBox1.Text = ofd.SafeFileName;
Excel.Application excelApp = new Excel.Application();
excelApp.Visible = false;
string filename = ofd.FileName;
Excel.Workbook workbook = excelApp.Workbooks.Open(filename);
Excel.Worksheet worksheet = workbook.Worksheets[1];
dataGridView1.ColumnCount = 2;
dataGridView1.Columns[0].Name = "Number";
dataGridView1.Columns[1].Name = "Street";
int rows = worksheet.UsedRange.Rows.Count;
for (int i = 2; i <= rows; i++)
{
string combinehr = worksheet.Cells[i, 150].Text + worksheet.Cells[i, 151].Text;
dataGridView1.Rows.Add(worksheet.Cells[i,29].Text, combinehr);
}
}
How do i expand it that it works like i want?
I would be so grateful
(sorry for the english)

With a reference to ExcelDataReader, ExcelDataReader.DataSet and DataSetExtensions (.Net) you can read the Excel file pretty easy into a DataSet, then you just have to work with the logic:
Input file:
using System;
using System.Data;
using System.IO;
using System.Linq;
using ExcelDataReader;
public DataTable GetTableFromExcel(string filePath)
{
DataSet ds = new DataSet();
using (var stream = System.IO.File.Open(filePath, System.IO.FileMode.Open, System.IO.FileAccess.Read))
{
using (var reader = ExcelReaderFactory.CreateReader(stream))
{
ds = reader.AsDataSet();
}
}
DataTable table = new DataTable();
table.Columns.Add(new DataColumn("CustomerNr"));
table.Columns.Add(new DataColumn("Address"));
// Set column names
for (int i = 0; i < ds.Tables[0].Columns.Count; i++)
{
// DataColumn.ColumnName can't be empty when DataColumn is part
// of a DataTable (throws ArgumentException)
string columnName = ds.Tables[0].Rows[0][i].ToString();
if (string.IsNullOrWhiteSpace(columnName))
{
columnName = $"Column{i}";
}
ds.Tables[0].Columns[i].ColumnName = columnName;
}
// Remove the first row containing the headers
ds.Tables[0].Rows.Remove(ds.Tables[0].Rows[0]);
// I don't have the benchmarks with me right now, but I've tested
// DataTable.Select vs DataTable.AsEnumerable.Select many times
// and the AsEnumerable method its faster, that's why you need the
// reference to System.Data.DataSetExtensions
var enumerableTable = ds.Tables[0].AsEnumerable();
// list of unique products
var products = enumerableTable.Select(row => row.Field<string>("Product")).Distinct();
// Add a column for each product
foreach (string product in products)
{
table.Columns.Add(new DataColumn(product));
}
// list of unique customers
var customerNumbers = enumerableTable.Select(row => row.Field<double>("CustomerNr")).Distinct();
foreach (var customerNumber in customerNumbers)
{
DataRow record = table.NewRow();
record["CustomerNr"] = customerNumber;
record["Address"] = enumerableTable.First(row => row.Field<double>("CustomerNr").Equals(customerNumber))[1];
for (int i = 2; i < table.Columns.Count; i++)
{
DataRow product = enumerableTable.FirstOrDefault(row => row.Field<double>("CustomerNr").Equals(customerNumber)
&& row.Field<string>("Product").Equals(table.Columns[i].ColumnName));
// Quantity = 0 if product is null
record[i] = product?["Quantity"] ?? 0;
}
table.Rows.Add(record);
}
return table;
}
Result DataTable:

The same result as #IvanGarcíaTopete via Microsoft.Office.Interop.Excel.
Class ExcelModel for Excel data:
public class ExcelModel
{
public string CustomerNr { get; set; }
public string Address { get; set; }
public string Product { get; set; }
public string Quantity { get; set; }
}
Read Excel and fill out model:
private void OpenReadExcel()
{
var dlg = new OpenFileDialog();
if (dlg.ShowDialog() != DialogResult.OK) return;
var exApp = new Microsoft.Office.Interop.Excel.Application();
Workbook exWbk = exApp.Workbooks.Open(dlg.FileName);
Worksheet wSh = exWbk.Sheets[1];
int k = 2;
Customers.Clear();
while (wSh.Cells[k, 1].Text != "" && wSh.Cells[k, 1].Value != null)
{
var rowExcelModel = new ExcelModel()
{
CustomerNr = wSh.Cells[k, 1].Text,
Address = wSh.Cells[k, 2].Text,
Product = wSh.Cells[k, 3].Text,
Quantity = wSh.Cells[k, 4].Text
};
Customers.Add(rowExcelModel);
k++;
}
exApp.Quit();
}
Generate Data table:
private void GenerateDataTable()
{
// unique products and customers
var products = Customers.Select(x => x.Product).Distinct().ToList();
var customers = Customers.Select(x => x.CustomerNr).Distinct().ToList();
// columns CustomerNr and Address
var dataTable = new System.Data.DataTable();
dataTable.Columns.Add(new DataColumn("CustomerNr"));
dataTable.Columns.Add(new DataColumn("Address"));
// columns for each product
foreach (var product in products)
{
dataTable.Columns.Add(new DataColumn(product));
}
//fill rows for each customers
foreach (var customer in customers)
{
var row = dataTable.NewRow();
row["CustomerNr"] = customer;
row["Address"] = Customers.Where(x => x.CustomerNr == customer).Select(x => x.Address).FirstOrDefault();
foreach (var product in products)
{
var quantity = Customers.Where(x => x.CustomerNr == customer && x.Product == product)
.Select(x => x.Quantity).FirstOrDefault();
row[product] = quantity ?? "0";
}
dataTable.Rows.Add(row);
}
dataGridView1.DataSource = dataTable;
}

Suspected issues with disposing Excel objects causing subsequent selenium tests to fail?

I've created several Selenium tests in C# for testing a login page. Each test uses a different pair of credentials sourced from the same Excel spreadsheet, and each runs great by itself. I found a great bit of code on the web for being able to read the Excel spreadsheet and locating the data in a specific row for use. The problem that I'm running into is that the tests only run to completion in isolation and not when they are run in a series. In the latter case, only the first one succeeds whereas all the subsequent tests fail with a "text cannot be null" exception. I am suspicious that it could be something to do with Excel not getting disposed of properly between each test. Any ideas on how I can properly clean up the Excel stuff?
Here is the code where I instantiate the Excel object:
string path1 = Path.Combine(AppDomain.CurrentDomain.SetupInformation.ApplicationBase, #"SeleniumData\LoginBook.xlsx");
ExcelLib loginBook = new ExcelLib(path1);
Here is where I call the workbook:
rmMain_PageObject pageRMMain = new rmLogin_PageObject().Login(loginBook.ReadData(1, "UserName"), (loginBook.ReadData(1, "Password")));
Here is the method itself:
using Excel;
using System;
using System.Collections.Generic;
using System.Data;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace AutoTestProject1
{
public class ExcelLib
{
private DataTable ExcelToDataTable(string fileName)
{
//open file and returns as Stream
FileStream stream = File.Open(fileName, FileMode.Open, FileAccess.Read);
//Createopenxmlreader via ExcelReaderFactory
IExcelDataReader excelReader = ExcelReaderFactory.CreateOpenXmlReader(stream); //.xlsx
//Set the First Row as Column Name
excelReader.IsFirstRowAsColumnNames = true;
//Return as DataSet
DataSet result = excelReader.AsDataSet();
//Get all the Tables
DataTableCollection table = result.Tables;
//Store it in DataTable
DataTable resultTable = table["Sheet1"];
//return
return resultTable;
}
public ExcelLib(string fileName)
{
PopulateInCollection(fileName);
}
public class Datacollection
{
public int rowNumber { get; set; }
public int colNumber { get; set; } //test
public string colName { get; set; }
public string colValue { get; set; }
}
static List<Datacollection> dataCol = new List<Datacollection>();
private void PopulateInCollection(string fileName)
{
DataTable table = ExcelToDataTable(fileName);
//Iterate through the rows and columns of the Table
for (int row = 1; row <= table.Rows.Count; row++)
{
//for (int col = 0; col <= table.Columns.Count; col++)
for (int col = 0; col < table.Columns.Count; col++)
{
Datacollection dtTable = new Datacollection()
{
rowNumber = row,
colNumber = col, //test
colName = table.Columns[col].ColumnName,
colValue = table.Rows[row - 1][col].ToString()
};
//Add all the details for each row
dataCol.Add(dtTable);
}
}
}

var excelObject = new ExcelObject //what ever excel assy you are using
try{
}
catch(Exception e){
}
finally{
excelObject.Dispose();
}

C# Read a particular value from CSV file [duplicate]

This question already has answers here:
Reading CSV file and storing values into an array
(21 answers)
Closed 8 years ago.
I am a learner in C#. I want to read a particular value from the CSV file. I have learned the getting the csv file into a datatable through browsing. Please see the following code (Thanks to surendra jha) and my CSV file format. Say, I want to get what is the 'Volume' for 'ID' = 90.
CSV file
ID:Volume:Name
100:5600:A
95:5000:B
90:4500:C
85:4000:D
Code for getting all the values:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.IO;
using System.Data;
namespace DVHConsolePrj
{
class Program
{
static void Main(string[] args)
{
readCsvFileData();
}
static void readCsvFileData()
{
string path = #"C:\IDVolumeName.txt";
StreamReader streamreader = new StreamReader(path);
DataTable datatable = new DataTable();
int rowcount = 0;
string[] columnname = null;
string[] streamdatavalue = null;
while (!streamreader.EndOfStream)
{
string streamrowdata = streamreader.ReadLine().Trim();
if (streamrowdata.Length > 0)
{
streamdatavalue = streamrowdata.Split(':');
if (rowcount == 0)
{
rowcount = 1;
columnname = streamdatavalue;
foreach (string csvheader in columnname)
{
DataColumn datacolumn = new DataColumn(csvheader.ToUpper(), typeof(string));
datacolumn.DefaultValue = string.Empty;
datatable.Columns.Add(datacolumn);
}
}
else
{
DataRow datarow = datatable.NewRow();
for (int i = 0; i < columnname.Length; i++)
{
datarow[columnname[i]] = streamdatavalue[i] == null ? string.Empty : streamdatavalue[i].ToString();
}
datatable.Rows.Add(datarow);
}
}
}
streamreader.Close();
streamreader.Dispose();
foreach (DataRow dr in datatable.Rows)
{
string rowvalues = string.Empty;
foreach (string csvcolumns in columnname)
{
rowvalues += csvcolumns + "=" + dr[csvcolumns].ToString() + " ";
}
Console.WriteLine(rowvalues);
}
Console.ReadLine();
}
}
}

Instead of parsing the file manually in a DataTable, then doing some Linq, use Linq directly on it, using this library.
It works pretty well and is very efficient with big files.
For instance.
1) Add nuget package in your project, and the following line to be able to use it:
using LINQtoCSV;
2) define the class that olds the data
public class IdVolumeNameRow
{
[CsvColumn(FieldIndex = 1)]
public string ID { get; set; }
[CsvColumn(FieldIndex = 2)]
public decimal Volume { get; set; }
[CsvColumn(FieldIndex = 3)]
public string Name{ get; set; }
}
3) and search for the value
var csvAttributes = new CsvFileDescription
{
SeparatorChar = ':',
FirstLineHasColumnNames = true
};
var cc = new CsvContext();
var volume = cc.Read<IdVolumeNameRow>(#"C:\IDVolumeName.txt", csvAttributes)
.Where(i => i.ID == "90")
.Select(i => i.Volume)
.FirstOrDefault();

public DataTable CSVToDataTable(string filename, string separator)
{
try
{
FileInfo file = new FileInfo(filename);
OleDbConnection con =
new OleDbConnection("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=\"" +
file.DirectoryName + "\";
Extended Properties='text;HDR=Yes;FMT=Delimited(" + separator + ")';")
OleDbCommand cmd = new OleDbCommand(string.Format
("SELECT * FROM [{0}]", file.Name), con);
con.Open();
DataTable tbl = new DataTable();
using (OleDbDataAdapter adp = new OleDbDataAdapter(cmd))
{
tbl = new DataTable("MyTable");
adp.Fill(tbl);
}
return tbl;
}
catch(Exception ex)
{
throw ex;
}
finally()
{
con.Close();
}
}
You can try this code, it is build on the fly, it is possible little errors to exist. Check OleDbConnection. When you return the DataTable you can search in the table using LINQ.
var results = from myRow in myDataTable.AsEnumerable()
where myRow.Field<int>("ID") == 90
select myRow;
Here you can take the row with ID=90 !

For filtering DataTable you can use DataTable.Select method like this
var filtered = dataTable.Select("ID = '90'");
filtered above is array of datarow that suitable for the condition, so for get value from first filtered row you can use something like
if(filtered.Length>0){
var Volume = filtered[0]["VOLUME"];
}