Change Workflow Task Status from any SharePoint custom component

Scenario: I have a custom workflow running. I want to change status a task from another sharepoint custom component like webpart or so.

Approach:
If we update the workflow task directly by changing the status field value to Completed or to any other status, then usually workflow raises an exception "This task is currently locked by a running workflow and cannot be edited." To get rid of this error, you can use following routine:

private void CompleteTask(string taskTitle)
{
   try
   {
      Hashtable taskHash = new Hashtable();
      taskHash[SPBuiltInFieldId.TaskStatus] = "Completed";

      string currentuser = SPContext.Current.Web.CurrentUser.Name.ToLower();
      Guid siteID = SPContext.Current.Site.ID;
      Guid webID = SPContext.Current.Web.ID;

      SPSecurity.RunWithElevatedPrivileges(delegate()
      {
          using (SPSite site = new SPSite(siteID))
          {
              using (SPWeb web = site.OpenWeb(webID))
              {
                 web.AllowUnsafeUpdates = true;
                 SPList wfTasksList = web.Lists["WorkflowTasks"];
                 SPQuery queryWFTasks = new SPQuery();
                 queryWFTasks.Query = <<>>;
                 queryWFTasks.ViewAttributes = "Scope=\"RecursiveAll\"";

                 SPListItemCollection wfTaskItems = wfTasksList.GetItems(queryWFTasks);

                 if (wfTaskItems.Count != 0)
                 {
                    foreach (SPListItem item in wfTaskItems)
                    {
                        if (item.Title.ToLower().Equals(taskTitle.ToLower()))
                        {
                           SPWorkflowTask.AlterTask(item, taskHash, true);
                           break;
                        }
                    }
                 }
                
                 web.AllowUnsafeUpdates = false;
               }
            }
       });
    }
    catch (Exception ex)
    {
      // Log the exception here
    }
}