Read Excel File In Windows Application Using C#

Step 8. You can also open the code behind the file by double-clicking on the buttons. It will create the click event method of the button.

Step 9. You can also manage the click event of the button in its Properties.

Step 10. Now create a method ReadExcel, which returns a data table using the following logic.

/// <summary>
/// this method will read the excel file and copy its data into a datatable
/// </summary>
/// <param name="fileName">name of the file</param>
/// <returns>DataTable</returns>
private DataTable ReadExcel(string fileName) {
    WorkBook workbook = WorkBook.Load(fileName);
    //// Work with a single WorkSheet.
    ////you can pass static sheet name like Sheet1 to get that sheet
    ////WorkSheet sheet = workbook.GetWorkSheet("Sheet1");
    //You can also use workbook.DefaultWorkSheet to get default in case you want to get first sheet only
    WorkSheet sheet = workbook.DefaultWorkSheet;
    //Convert the worksheet to System.Data.DataTable
    //Boolean parameter sets the first row as column names of your table.
    return sheet.ToDataTable(true);
}

Let's discuss something about the ReadExcel() method.

This method will read the file data in the Workbook class object. Here you can perform a lot of operations on Workbook class objects.

You can get the Workbook data in a data set or data table directly by using 1 line of code.

Similarly, you can do a lot of operations with this component.

Step 11. Add the following logic in button click events.

 /// <summary>
 /// this method will choose and read the excel file
 /// </summary>
 /// <param name="sender"></param>
 /// <param name="e"></param>
 private void btnChoose_Click(object sender, EventArgs e) {
     OpenFileDialog file = new OpenFileDialog(); //open dialog to choose file
     if (file.ShowDialog() == DialogResult.OK) //if there is a file chosen by the user
     {
         string fileExt = Path.GetExtension(file.FileName); //get the file extension
         if (fileExt.CompareTo(".xls") == 0 || fileExt.CompareTo(".xlsx") == 0) {
             try {
                 DataTable dtExcel = ReadExcel(file.FileName); //read excel file
                 dataGrdView.Visible = true;
                 dataGrdView.DataSource = dtExcel;
             } catch (Exception ex) {
                 MessageBox.Show(ex.Message.ToString());
             }
         } else {
             MessageBox.Show("Please choose .xls or .xlsx file only.", "Warning", MessageBoxButtons.OK, MessageBoxIcon.Error); //custom messageBox to show error
         }
     }
 }
 /// <summary>
 /// this method will close the windows form
 /// </summary>
 /// <param name="sender"></param>
 /// <param name="e"></param>
 private void btnCancel_Click(object sender, EventArgs e) {
     this.Close(); //to close the window(Form1)
 }

After choosing the file Result will be like the following whether you upload a .xls or .xlsx file.

Conclusion

The IronXL is also helpful in other Excel operations like editing/styling/generating Excel files. The code of this tutorial is attached. You can download the code, play with the code, and modify it according to your requirements. I tried to make this tutorial as development-friendly friendly as simple as I could. Thank you, and enjoy coding!!!