public void DeleteCategory()
{
//Deleting Empty Category:
var cc = CreateCategory(null, "Delete test");
var res4 = _api.DeleteCategory(cc.Id);
Assert.IsNotNull(res4);
Assert.AreEqual(ResultState.Deleted, res4);
//Deleting not existing category:
var res = _api.DeleteCategory(9846774);
Assert.IsNotNull(res);
Assert.AreEqual(ResultState.Error, res);
//Deleting category with subcategories
var cc1 = CreateCategory(null, "Delete test ROOT");
var cc2 = CreateCategory(cc1.Id, "Delete test SUB");
var res2 = _api.DeleteCategory(cc1.Id);
Assert.IsNotNull(res2);
Assert.AreEqual(ResultState.Deleted, res2);
//Deleting Category with topics:
var cct = CreateCategory(null, "Delete test Topic");
var topic = CreateTopic(cct.Id);
var res3 = _api.DeleteCategory(23);
Assert.IsNotNull(res3);
Assert.AreEqual(ResultState.Deleted, res3);
}