sharepoint SPFarm.local.GetObject return null - sharepoint

Question

I installed sharepoint foundation 2010 (in 'Standalone' type) on windows 2012 r2.
And I created a windows app project.
When Load , New Counter(farm) is success.
But, SPFarm.local.GetObject return null;
Does someone konw the reason,please help me.
source like this:
//-------source start-------
//Counter.cs
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Microsoft.SharePoint;
using Microsoft.SharePoint.Administration;
namespace WinAppTest
{
class Counter : SPPersistedObject
{
public static String SettingName = "Counter";
public static String SettingGuid = "62648e50-8aee-42b2-b074-2f49ced85587";
[Persisted]
public String name;
[Persisted]
public String count;
public Counter()
{
}
public Counter(SPPersistedObject parent)
: base(SettingName, parent, new Guid(SettingGuid))
{
}
}
}
// Form1.cs
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using Microsoft.SharePoint.Administration;
namespace WinAppTest
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void Write_Click(object sender, EventArgs e)
{
SPFarm farm = SPFarm.Local;
//------- *conf is null*-----
Counter conf = (Counter)farm.GetObject(new Guid(Counter.SettingGuid));
//------- *conf is null*-----
conf.Name = "pf1";
conf.count = "1";
conf.Update();
}
private void Form1_Load(object sender, EventArgs e)
{
SPFarm farm = SPFarm.Local;
Counter conf = (Counter)farm.GetObject(new Guid(Counter.SettingGuid));
if (conf == null)
{
conf = new Counter(farm);
}
//------- *conf is null*-----
conf = (Counter)farm.GetObject(new Guid(Counter.SettingGuid));
//------- *conf is null*-----
String name = conf.name;
String count = conf.count;
}
}
}

Answer 1

Finally , I think the source has error in it.
modify like this, It's OK.
private void Write_Click(object sender, EventArgs e)
{
SPFarm farm = SPFarm.Local;
Counter conf = (Counter)farm.GetObject(new Guid(Counter.SettingGuid));
if (conf == null)
{
conf = new Counter(farm);
}
conf.Name = "pf1";
conf.count = "1";
conf.Update();
}
private void Form1_Load(object sender, EventArgs e)
{
SPFarm farm = SPFarm.Local;
Counter conf = (Counter)farm.GetObject(new Guid(Counter.SettingGuid));
String name = conf.name;
String count = conf.count;
}