title: How to clear observable properties in knockout?
body: <p>I have javascript code block and html like below. The model object is a generic. 
  It is defined at run time.</p>
  
  <p>It can be like this. </p>
  
  <pre><code>var model = { "xId": ko.observable(0), "xName": ko.observable(null), "Type": ko.observable("x") };
     /* var model = { "yId": ko.observable(0), "yName": ko.observable(null), "Type": ko.observable("y") };
      var model = { "zId": ko.observable(0), "zName": ko.observable(null), "Type": ko.observable("z") };  */
  
      var vm = function (data) {
          ko.mapping.fromJS(data, {}, this);
      };
  
      var vm2 = function () {
          var self = this;
          self.New = ko.observable(null);
          self.NewItem = function () {
              console.log(model);
              self.New(new vm(model));
          };
      };
  
      var viewModel = new vm2();
      ko.applyBindings(viewModel);
  
      vm.prototype.Save = function () {
          viewModel.New(null);
          /*In here all of inputs must be cleared but How to :)*/
      };
  </code></pre>
  
  <p>The newForm for first model.</p>
  
  <pre><code>&lt;input type="button" data-bind="click: NewItem" value="Add" /&gt;
  &lt;div data-bind="with:New" id="newForm"&gt;
      &lt;input type="text" data-bind="value:xId" /&gt;
      &lt;input type="text" data-bind="value:xName" /&gt;
      &lt;input type="text" data-bind="value:Type" /&gt;
      &lt;input type="button" data-bind="click: Save" value="Save" /&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>I click the add button, then I tpye sometings to inputs, then I click the save button. 
  The newForm is invisible. So far everything is ok. But I click the add button again, I had written values ​​are still in the inputs. I can't clear the newForm after save.  </p>
  
  <p>EDIT:</p>
  
  <pre><code>public class Test{
      public int TestId {get; set;}
      public int TestName {get; set;}
  }
  
  public class Test2{
      public int Test2Id {get; set;}
      public int Test2Name {get; set;}
  }
  </code></pre>
  
  <p>The coutn of entity classes is not clear.</p>
  
  <p>My entity classes is converted json. the model is create by .net like this.
  My project have a master page and subpages. 
  for test page :</p>
  
  <pre><code>var model = &lt;%=ViewModelCreator.Create&lt;Test&gt;() %&gt;;
  </code></pre>
  
  <p>for test2 page :</p>
  
  <pre><code>var model = &lt;%=ViewModelCreator.Create&lt;Test2&gt;() %&gt;;
  </code></pre>