求助：关于usercontrol的一个小问题，一个困扰很久的问题

创建一个自定义控件

namespace testcontrolnull
{
    public partial class UserControl1 : UserControl
    {
        public UserControl1()
        {
            InitializeComponent();
        }

        private entity e;

        public entity E
        {
            get { return e; }
            set { e = value; }
        }
    }

    public class entity
    {
        private decimal myVar;

        public decimal MyProperty
        {
            get { return myVar; }
            set { myVar = value; }
        }
    }
}

使用该控件，将其拖动到某窗体时，会自动生成如下代码：
 this.userControl11.E = null;
            this.userControl11.Location = new System.Drawing.Point(182, 146);
            this.userControl11.Name = "userControl11";
            this.userControl11.Size = new System.Drawing.Size(57, 77);
            this.userControl11.TabIndex = 0;

怎么让不产生 this.userControl11.E = null;

谢谢o(∩_∩)o...