Алексей

public ObservableCollection<Person>  FilteredCollection
        {
            get
            {
   return  new ObservableCollection<Person>(PersonCollection.Where(i => FilteredCheck(i)));
            }
        }

public bool FilteredCheck(DemandHead item)
        {
            bool Accept=true;
// организовываем проверку как вашей душе удобно
}

// И дальше при изменении фильтра оповещаем View об изменении данных
        public bool IsFilterEnabled
        {
            get
            {
                return _IsFilterEnabled;
            }

            set
            {
                _IsFilterEnabled = value;
                base.OnPropertyChanged("IsFilterEnabled");
                base.OnPropertyChanged("FilteredCollection");

            }
        }

public DataTable ToDataTable<T>(List<T> items)
        {
            var tb = new DataTable(typeof(T).Name);

            PropertyInfo[] props = typeof(T).GetProperties(BindingFlags.Public | BindingFlags.Instance);

            foreach (PropertyInfo prop in props)
            {
                Type t = GetCoreType(prop.PropertyType);
                tb.Columns.Add(prop.Name, t);
            }


            foreach (T item in items)
            {
                var values = new object[props.Length];

                for (int i = 0; i < props.Length; i++)
                {
                    values[i] = props[i].GetValue(item, null);
                }

                tb.Rows.Add(values);
            }    return tb;
        }

 public static bool IsNullable(Type t)
        {
            return !t.IsValueType || (t.IsGenericType && t.GetGenericTypeDefinition() == typeof(Nullable<>));
        }

 public static Type GetCoreType(Type t)
        {
            if (t != null && IsNullable(t))
            {
                if (!t.IsValueType)
                {
                    return t;
                }
                else
                {
                    return Nullable.GetUnderlyingType(t);
                }
            }
            else
            {
                return t;
            }
        }

private void CollectionViewSource_Filter(object sender, FilterEventArgs e)
        {
            cgAssortment cgA = e.Item as cgAssortment;
            bool isAccept = true;

            if (cgA != null)
            {
                try
                {
                    isAccept = isAccept && (!this.cbOnLink.IsChecked.Value || (this.cbOnLink.IsChecked == true && (cgA.Group5GUID == null)));
                    isAccept = isAccept && (!this.cbInMatrix.IsChecked.Value || (this.cbInMatrix.IsChecked == true && (cgA.InMatrix == true)));
                    isAccept = isAccept && (!this.dgGoodsAllF1.IsChecked.Value || (this.dgGoodsAllF1.IsChecked.Value && cgA.Code.ToString() == this.dgGoodsAllT1.Text));
                    isAccept = isAccept && (!this.dgGoodsAllF2.IsChecked.Value || (this.dgGoodsAllF2.IsChecked.Value && (cgA.NameLong.ToUpper().Contains(this.dgGoodsAllT2.Text.ToUpper()))));
                    isAccept = isAccept && (!this.dgGoodsAllF3.IsChecked.Value || (this.dgGoodsAllF3.IsChecked.Value && (cgA.cgGroup2.NameLong.ToUpper().Contains(this.dgGoodsAllT3.Text.ToUpper()))));
                    isAccept = isAccept && (!this.dgGoodsAllF4.IsChecked.Value || (this.dgGoodsAllF4.IsChecked.Value && cgA.cgGroup3 != null && (cgA.cgGroup3.NameLong.ToUpper().Contains(this.dgGoodsAllT4.Text.ToUpper()))));
                    isAccept = isAccept && (!this.dgGoodsAllF5.IsChecked.Value || (this.dgGoodsAllF5.IsChecked.Value && cgA.cgGroup4 != null && (cgA.cgGroup4.NameLong.ToUpper().Contains(this.dgGoodsAllT5.Text.ToUpper()))));
                    isAccept = isAccept && (!this.dgGoodsAllF6.IsChecked.Value || (this.dgGoodsAllF6.IsChecked.Value && cgA.cgGroup5 != null && (cgA.cgGroup5.NameLong.ToUpper().Contains(this.dgGoodsAllT6.Text.ToUpper()))));
                    isAccept = isAccept && (!this.dgGoodsAllF7.IsChecked.Value || (this.dgGoodsAllF7.IsChecked.Value && cgA.cgGroup6 != null && (cgA.cgGroup6.NameLong.ToUpper().Contains(this.dgGoodsAllT7.Text.ToUpper()))));
                    isAccept = isAccept && (!this.dgGoodsAllF8.IsChecked.Value || (this.dgGoodsAllF8.IsChecked.Value && cgA.cgGroup7 != null && (cgA.cgGroup7.NameLong.ToUpper().Contains(this.dgGoodsAllT8.Text.ToUpper()))));
                    isAccept = isAccept && (!this.dgGoodsAllF9.IsChecked.Value || (this.dgGoodsAllF9.IsChecked.Value && cgA.cgGroup8 != null && (cgA.cgGroup8.NameLong.ToUpper().Contains(this.dgGoodsAllT9.Text.ToUpper()))));
                }
                catch (Exception er )
                {
                    MessageBox.Show(er.Message);
                }
                e.Accepted = isAccept;
            }
        }