Create operation using UmbracoApiController :

create.html

<div class="umb-dialog-body with-footer">
    <div class="umb-pane">
        <h5><localize key="create_createUnder">Create Template under </localize> {{currentNode.name}}</h5>
      
       
        <ul class="umb-actions umb-actions-child">
            <li>
                <a href="#/Templates/TemplateTree/new/true" ng-click="nav.hideNavigation()">
                    <i class="icon-document"></i>
                    <span class="menu-label">
                        New custom item{{currentNode.name}}
                       
                        <small>Click here to create template under {{currentNode.name}} </small>
                    </span>
                </a>
            </li>
        </ul>
    </div>
</div>
<div class="umb-dialog-footer btn-toolbar umb-btn-toolbar">
    <button class="btn" ng-click="nav.hideDialog()">
        <localize key="buttons_somethingElse">Do something else</localize>
    </button>
</div>
 

createCtrl.js

angular.module("umbraco").controller('CreateCtrl',
    function($scope, $http, $location, $rootScope) {
        debugger;
        $scope.action = "save";
        $scope.saving = false;

        $rootScope.alert = false;

        $scope.save = function() {
            $scope.saving = true;
                
            $http({ method: 'POST', url: '/umbraco/api/StatusApi/PostStatus/', params: { parent: 1  }, data: $scope.status })
                .success(function(data) {
                    $rootScope.alert = true;
                    $rootScope.alertMessage = "New status added";
                    $scope.saving = false;
                    $location.path('/list');

                })
                .error(function() {
                    $scope.error = "An Error has occured while submitting!";
                    $scope.saving = false;
                });
        }
    });

//}

new.html

    <div class="umb-panel" ng-controller="CreateCtrl">
     <div class="umb-panel-header">
         <div class="row-fluid">
           <div class="span12">
      <h1><span class="icon-documents"></span> Email Template</h1>
       </div>
            </div>
    </div>
            <div class="umb-panel-body">
	   <form name="createForm" class="form-horizontal">
       <br>
            
                <!-- control for subject-->
            <div class="control-group">
                <label for="title" class="control-label">Title</label>
                <div class="controls">
                    <input class="span5" id="title" type="text" ng-model="status.Title" 
                           required>
                </div>
            </div>
                <!-- control for Body-->
            <div class="control-group">
                <label for="message" class="control-label">Body</label>
                <div class="controls">
                    <textarea class="span5" id="message" ng-model="status.Message" rows="4"
                              required></textarea>
   
                </div>
            </div>
            <div class="form-actions">
				<a href="#/Templates" class="btn">Cancel</a>
                
                <button id="Email_Save" ng-click="save()" ng-disabled="isClean() || createForm.$invalid || saving"
                        class="btn btn-primary">Save</button>
                    </div>
			</form>
            </div>

     </div>

StatusApiController.cs

using Umbraco.Web.WebApi;
using Adweb_OTL.StatusModel;
using Umbraco.Core.Models;
using System.Web.Http;
using Umbraco.Web.Mvc;

namespace Adweb_OTL
{
  
    public class StatusApiController : UmbracoApiController
    {
        //Url route
        //umbraco/api/StatusApi/function_name
        private const string contentTypeAlias = "Status";
        private const string MessagePropertyAlias = "message";

        //Creates a new status document under the specified parent 
        [HttpPost]
        public Status PostStatus(Status status,int parentId)
        {
           
            System.Diagnostics.Debugger.Launch();
            var cs = Services.ContentService;
            var content = cs.CreateContent(status.Title, parentId, contentTypeAlias);
            content.Name = status.Title;
            content.SetValue(MessagePropertyAlias, status.Message);
            cs.SaveAndPublishWithStatus(content);
            status.Id = content.Id;
            return status;

            }
    }
}