title: <input> lostfocus/onblur event in knockout
body: <p>I want to execute an event on a knockout observable bound to an <code>input</code>. This function should be executed when the control lose focus, even without typing anything. I tried to change the event binding but it doesn't fire when the user moves away from the control without typing anything. I tried mouseout event, but that only fires when the user clicks elsewhere in the form, after losing focus - not exactly what I want. I want the even to fire as soon as the focus is moved away from the control, even with tab.</p>
  
  <p>Following is the code I used for mouseout event:</p>
  
  <pre><code>&lt;input
      type="text"
      id="txtFirstName"
      tabindex="1"
      maxlength="25"
      class="txtbox" 
      style="width: 200px;"
      data-bind="value: FirstName, 
                 attr: {title: FirstNameErrorMessage },
                 css: {validationFailed: !IsValidFirstName() },
                 event: {mouseout: ValidateFirstName}" 
  /&gt;
  
  this.ValidateFirstName = function () {
      self.IsValidFirstName(true);
      self.FirstNameErrorMessage('');
      if (self.FirstName() == '') {
          self.IsValidFirstName(false);
          self.FirstNameErrorMessage('First Name is required');
      }
  }
  </code></pre>
  
  <p>Can anyone help please?</p>