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A.AB.BC.CD.DYou create a Microsoft ASP.NET application ……

You create a Microsoft ASP.NET application by using the Microsoft .NET Framework version 3.5. You create two user controls named UserCtrlA.ascx and UserCtrlB.ascx. The user controls postback to the server. 
You create a new Web page that has the following ASPX code:  
<asp:CheckBox ID="Chk" runat="server"    
oncheckedchanged="Chk_CheckedChanged"   
AutoPostBack="true" />  
<asp:PlaceHolder ID="PlHolder" runat="server"></asp:PlaceHolder>  
To dynamically create the user controls, you write the following code segment for the Web page:  public void LoadControls() 
{ 
if (ViewState["CtrlA"] != null) 
{ 
Control c; 
if ((bool)ViewState["CtrlA"] == true) 
{ 
c = LoadControl("UserCtrlA.ascx"); 
} else { 
c = LoadControl("UserCtrlB.ascx"); 
}  
c.ID = "Ctrl"; 
PlHolder.Controls.Add(c); 
} 
}  
protected void Chk_CheckedChanged(object sender, EventArgs e) 
{ 
ViewState["CtrlA"] = Chk.Checked; PlHolder.Controls.Clear(); 
LoadControls(); 
}  
You need to ensure that the user control that is displayed meets the following requirements: It is recreated during postback It retains its state.  
Which method should you add to the Web page?()



A.A
B.B
C.C
D.D

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单项选择题You create a Microsoft ASP.NET application by using the Microsoft .NET Framework version 3.5. You create a Web form and add the following code fragment:   <asp:Repeater ID= rptData  runat= server  DataSourceID= SqlDataSource1  ItemDataBound= rptData_ItemDataBound >   <ItemTemplate>   <asp:Label ID= lblQuantity  runat= server     Text=’<%# Eval( QuantityOnHand ) %>’  >  < ItemTemplate>   < asp:Repeater>    The SqlDataSource1 DataSource control retrieves the Quantity column values from a table named Products.  You write the following code segment to create the rptData_ItemDataBound event handler:   01 protected void rptData_ItemDataBound(object sender,   02   RepeaterItemEventArgs e)   03 {   04   05   if(lbl != null)   06     if(int.Parse(lbl.Text) < 10)   07       lbl.ForeColor = Color.Red;   08 } You need to retrieve a reference to the lblQuantity Label control into a variable named lbl. Which code segment should you insert at line 04? ()

A.Label lbl = Page.FindControl("lblQuantity") as Label; 
B.Label lbl = e.Item.FindControl("lblQuantity") as Label; 
C.Label lbl = rptData.FindControl("lblQuantity") as Label; 
D.Label lbl = e.Item.Parent.FindControl("lblQuantity") as Label;