NumericUpDown类型的问题

public static void BindData<T>(this System.Windows.Forms.Control.ControlCollection controls, T bind)
    {
        foreach (Control control in controls)
        {
            if (control.GetType() == typeof(System.Windows.Forms.TextBox) || control.GetType().IsSubclassOf(typeof(System.Windows.Forms.TextBox)))
            {
                UtilityBindData(control, bind);
            }
            else
            {
                if (control.Controls.Count == 0)
                {
                    UtilityBindData(control, bind);
                }
                else
                {
                    control.Controls.BindData(bind);
                }
            }
        }
    }

    private static void UtilityBindData<T>(Control control, T bind)
    {
        Type type = control.GetType();

        PropertyInfo propertyInfo = type.GetProperty("BindingProperty");
        if (propertyInfo == null)
            propertyInfo = type.GetProperty("Tag");

// rest of the code....

System.Windows.Forms.Control.ControlCollection