问Ext - Ajax.request / Api.restActions？

EN

//** Insert - ajax.request **//

btnSave.on('click',function(){
   var unitname =  Ext.getCmp('unitname').getValue();
   var description =  Ext.getCmp('description').getValue();
          Ext.Ajax.request({
          url: '/units',
          method: 'POST',
          params: {'data[unitname]':unitname,'data[description]':description}
          });
          grid.store.reload();
          grid.show();
          myform.hide();
         });

    //** Update - restActions **//

    Ext.data.Api.restActions = {
                //create  : 'POST',
                //read    : 'GET',
                update  : 'PUT'
                //destroy : 'DELETE'
                };
    btnUpd.on('click',function(){
                  var store = Ext.getCmp('maingrid').getStore();
                  store.save();

                 }); //end update