title: how to read .xls and .xlsx and .xlsm files in c#
body: <p>I used openfiledialog and filter it to get: .xls and .xlsx and .xlsm files.
  but I don't know what to do next, I build a class of workers with firstName and lastName and I want to take the data from the excel file and put it in the varible. </p>
  
  <p>This is my code of the openfiledialog:</p>
  
  <pre><code> private void ExcelLoad_Click(object sender, EventArgs e)
      {
          int size = -1;
          openFileDialog1.Title = "Browse Excel file";
          openFileDialog1.Filter = "Excel Files|*.xls;*.xlsx;*.xlsm";
          DialogResult result = openFileDialog1.ShowDialog(); // Show the dialog.
          if (result == DialogResult.OK) // Test result.
          {
                  string file = openFileDialog1.FileName;
                  try
                  {
                      string text = File.ReadAllText(file);
                      size = text.Length;
                  }
                  catch (IOException)
                  {
                  }
          }
          Console.WriteLine(size); // &lt;-- Shows file size in debugging mode.
          Console.WriteLine(result); // &lt;-- For debugging use.
          Stream  excelOpenFile= openFileDialog1.OpenFile();
      }
  </code></pre>
  
  <p>so how can I read the data from this kind of files.(is succed to open it but i dont know how to use the file and get the data from it).</p>