title: How to Add Days to Datetime
body: <p>I have 2 date pickers txtbookin and txtcompleted </p>
  
  <p>And I have one more textbox named txtnoofdays which will accept only integers</p>
  
  <p>My Requirement:</p>
  
  <p>If I key-in any integers in txtnoofdays textbox, ontextchanged event I want to add txtnoofdays to txtbookin and display corresponding Date in txtcomplete..I am writing as below..
  but its adding to month instead of date..my system date format dd/MM/yyyy...</p>
  
  <pre><code> var dt1 =Convert.ToDateTime(txtbookindate.Text);
          var dt2 = Convert.ToDateTime(txtcompleted.Text);
          var dt3 = dt1.AddDays(Convert.ToDouble(txtnoofdays.Text));
          txtcompleted.Text = dt3.ToString("dd/MM/yyyy");
  </code></pre>