DevExpress ComboBoxEdit 添加值

今天在使用ComboBoxEdit 这个控件的时候,不知道怎么添加值.

在官网上找到代码。在这里做个记录

 ComboBoxEdit combo = new ComboBoxEdit();
  ComboBoxItemCollection coll = combo.Properties.Items;
  coll.BeginUpdate();
  try {
    coll.Add(new PersonInfo("Sven", "Petersen"));
    coll.Add(new PersonInfo("Cheryl", "Saylor"));
    coll.Add(new PersonInfo("Dirk", "Luchte"));
  }
  finally {
    coll.EndUpdate();
  }
  combo.SelectedIndex = -;

  Controls.Add(combo);

//... 

  public class PersonInfo {
    private string _firstName;
    private string _lastName;

    public PersonInfo(string firstName, string lastName) {
      _firstName = firstName;
      _lastName = lastName;
    }

    public override string ToString() {
      return _firstName + " " + _lastName;
    }
  }

 public class ExComboBox
    {
        public int Index { get; set; }
        public string Key { get; set; }
        public string Value { get; set; }
        public string Tag { get; set; }

        public ExComboBox(int pIndex, string pKey, string pValue)
        {
            this.Index = pIndex;
            this.Key = pKey;
            this.Value = pValue;
        }

        public ExComboBox(int pIndex, string pKey, string pValue, string pTag)
        {
            this.Index = pIndex;
            this.Key = pKey;
            this.Value = pValue;
            this.Tag = pTag;
        }
        public override string ToString()
        {
            return this.Value;
        }
    }

  comboBox.Properties.Items.Add("全部");
                 for (int i = ; i < arg.Result.Count; i++)
                      {
                         comboBox.Properties.Items.Add(new ExComboBox(i, arg.Result[i].F_RoadwayCode, arg.Result[i].F_StationCode.ToString()));
                       }

  void comboBoxEditStation_SelectedValueChanged(object sender, System.EventArgs e)
        {
            var exComboBox1 = this.comboBoxEditRoadWay.SelectedItem as ExComboBox;
｝