DataList保持顯示以前加載的數據列表

Question

我有一個目錄功能，用戶可以通過點擊單選按鈕來過濾他們的選擇。例如，通過選擇Dining radiobutton，所有與用餐相關的包都會出現。

而我使用DataList1.Items.Count方法來計算數字搜索結果。我已經在page_load中實現了這個方法，但是datalist數量的值繼續顯示以前加載的數據列表。

這裏是我的代碼：

protected void Page_Load(object sender, EventArgs e) 
    { 
     DataList1.DataSourceID = "SqlDataSource3"; 
     Label1.Text = DataList1.Items.Count.ToString(); 
    } 


    private SqlDataReader getReader() 
    { 
     //get connection string from web.config 
     string strConnectionString = ConfigurationManager.ConnectionStrings["ASPNETDBConnectionString1"].ConnectionString; 
     SqlConnection myConnect = new SqlConnection(strConnectionString); 

     string strCommandText = "SELECT CategoryID, CatName from Category"; 

     SqlCommand cmd = new SqlCommand(strCommandText, myConnect); 
     myConnect.Open(); 

     //DataList1.DataSource = reader; 

     DataList1.DataBind(); 

     // CommandBehavior.CloseConnection will automatically close connection 
     SqlDataReader reader = cmd.ExecuteReader(CommandBehavior.CloseConnection); 
     return reader; 
    } 

    protected void RadioButtonList1_SelectedIndexChanged(object sender, EventArgs e) 
    { 
     DataList1.DataSourceID = "SqlDataSource1"; 


     if (RadioButtonList1.SelectedIndex == 0) 
     { 
      Session["catID"] = 1; 

     } 
     else if (RadioButtonList1.SelectedIndex == 1) 
     { 
      Session["catID"] = 2; 

     } 
     else if (RadioButtonList1.SelectedIndex == 2) 
     { 
      Session["catID"] = 3; 

     } 
     else if (RadioButtonList1.SelectedIndex == 3) 
     { 
      Session["catID"] = 4; 

     } 
     else if (RadioButtonList1.SelectedIndex == 4) 
     { 
      Session["catID"] = 5; 

     } 

     else 
     { 
      Session["catID"] = 8; 

     } 

    } 

我曾試圖放置Item.Count在此代碼的其他地方，但同樣的問題依然存在..

Answer 1

Try this, 
protected void Page_Load(object sender, EventArgs e) 
{ 
    if(!Page.IsPostBack) 
    {   
     DataList1.DataSourceID = "SqlDataSource3"; 
     Label1.Text = DataList1.Items.Count.ToString(); 
    } 
}