列表框不會顯示值

Question

從我的用戶我試圖表明一個名爲PersonList列表框裏面價值

用戶控件代碼：

BindingList<NotifiablePerson> PerSonList = new BindingList<NotifiablePerson>(); 

SqlCommand prsonListCmd = new SqlCommand("SQL QUERY", conn); 
SqlDataReader dr = prsonListCmd.ExecuteReader(); 
if (dr.HasRows) 
    { 
     while (dr.Read()) 
     { 
      //collect value from database and save inside Fname and Lname variable 

      NotifiablePerson np = PerSonList.AddNew(); 
      np.FirstName = Fname; 
      np.LastName = Lname; 
     }    
    } 
PersonList.DisplayMember = "np.FirstName" + "np.LastName"; 
PersonList.ValueMember = "np.FirstName"; 
PersonList.DataSource = PerSonList; 

NotifiablePerson類代碼：

namespace SMS 
{ 
class NotifiablePerson : MyComponentModel.NotifyProperyChangedBase 
    { 
    private string _firstName; 
    public string FirstName 
     { 
     get { return _firstName; } 
     set{ 
      if (this.CheckPropertyChanged<string>("FirstName", ref _firstName, ref value)) 
      { 
       this.DisplayNameChanged(); 
      } 
      } 
     } 

    private string _lastName; 
    public string LastName 
     { 
     get { return _lastName; } 
     set{ 
      if (this.CheckPropertyChanged<string>("LastName", ref _lastName, ref value)) 
      { 
       this.DisplayNameChanged(); 
      } 
      } 
     } 

     public string DisplayName 
     { 
      get { return _firstName + " " + _lastName; } 
     } 

     private void DisplayNameChanged() 
     { 
      this.FirePropertyChanged("DisplayName"); 
     } 
    } 
} 

但列表框只顯示一個列表SMS.NotifiablePerson，而不是我指定的實際值。這裏我設置了valuemember。它能正常工作並在sidebox中顯示相關值。但是隻有列表框不顯示正確的值。

這段代碼有什麼問題？

Answer 1

嘗試改變這一點：

PersonList.DisplayMember = "np.FirstName" + "np.LastName"; 

要這樣：

PersonList.DisplayMember = "DisplayName";