DevExpress控件（二）动态创建ASPxComboBox

以下代码是实现动态创建ASPxComboBox控件，以及在运行时给控件赋Callback Event, 从而实现两个ASPxComboBox控件数据联动的效果(populating on the fly), 静态效果的实现可参照：http://demos.devexpress.com/ASPxEditorsDemos/ASPxComboBox/ClientAPI.aspx

 

 

代码

 1  protected void Page_Load(object sender, EventArgs e)
 2         {
 3             ASPxComboBox cbxMain = new ASPxComboBox();
 4             cbxMain.ID = "cbx_Main";
 5             cbxMain.DataSource = SQLHELPER.GetDataSet("select eat, name from main_table");
 6             cbxMain.ClientInstanceName = "cbx_Main";
 7             cbxMain.TextField = "name";
 8             cbxMain.ValueField = "eat";
 9             cbxMain.DataBind();
10             cbxMain.ClientSideEvents.SelectedIndexChanged = "function(s, e) { OnCountryChanged(s); }";
11 
12             ASPxComboBox cbxSub = new ASPxComboBox();
13             cbxSub.ID = "cbx_Sub";
14             cbxSub.ClientInstanceName = "cbx_Sub";
15             cbxSub.Callback += new DevExpress.Web.ASPxClasses.CallbackEventHandlerBase(cbxSub_Callback);
16 
17             //注册脚本
18             string js = "<script language=\"javascript\">function OnCountryChanged(cbx_Main) { ";
19             js += "cbx_Sub.PerformCallback(cbx_Main.GetValue().toString());";
20             js += "}</script>";
21 
22             ClientScript.RegisterClientScriptBlock(this.GetType(), "OnCountryChanged", js);
23             pnl_DDL.Controls.Add(cbxMain);
24             pnl_DDL.Controls.Add(cbxSub);
25         }
26 
27         protected void cbxSub_Callback(object source, DevExpress.Web.ASPxClasses.CallbackEventArgsBase e)
28         {
29             ASPxComboBox cbxSub = source as ASPxComboBox;
30             ASPxComboBox cbxMain = this.pnl_DDL.FindControl("cbx_Main") as ASPxComboBox;
31             string value = "";
32             if (cbxMain.SelectedItem != null)
33                 value = cbxMain.SelectedItem.Value.ToString();
34             string subSQL = "select * from sub_table where eat='" + value + "'";
35             cbxSub.DataSource = SQLHELPER.GetDataSet(subSQL);
36             
37             cbxSub.TextField = "E";
38 
39             cbxSub.ValueField = "eaf";
40             cbxSub.DataBind();
41         }