Wednesday, March 28, 2012

Updating a DataList with UpdatePanel

I've been trying to update my DataList with UpdatePanel but it's not working.

What I have is a text field for a user to enter comments and a save button, along with a DataList control all in an UpdatePanel.

Data is being saved on the table when the save button is clicked but the DataList is not updated unless I refresh the browser. What am I doing wrong?

Here is my ASP code:

 <asp:UpdatePanel ID="UpdatePanel3" runat="server"> <ContentTemplate> <asp:Panel ID="PanelCommentBody" runat="server" CssClass="collapsePanel" Width="451px"><br /> <asp:TextBox ID="txtComments" runat="server" Height="45px" TextMode="MultiLine" Width="412px" ValidationGroup="cmnts" ></asp:TextBox><br /> <asp:Label ID="lblComment" runat="server" Text="" Font-Size="Small"></asp:Label> <asp:RequiredFieldValidator ID="RFVComments" runat="server" ErrorMessage="Please enter comment." ValidationGroup="cmnts" ControlToValidate="txtComments" Font-Size="Small" Width="154px"></asp:RequiredFieldValidator> <asp:Button ID="bttnPostComment" runat="server" Text="Post Comment" OnClick="bttnPostComment_Click" ValidationGroup="cmnts" Width="122px" /> <asp:Button ID="bttnDiscard" runat="server" Text="Discard" OnClick="bttnDiscard_Click" CausesValidation="false" /> </asp:Panel> <cc1:CollapsiblePanelExtender ID="CollapsiblePanelExtender2" runat="server" CollapseControlID="closeComment" ExpandControlID="closeComment" TargetControlID="PanelCommentBody" Collapsed="true" SuppressPostBack="true"> </cc1:CollapsiblePanelExtender> <asp:DataList ID="DataList1" runat="server" DataSourceID="SqlDataSource1" Width="307px" Font-Size="Small"> <ItemTemplate> <strong>From: <a href="../Default.aspx?urnm=<%# Eval("UserName")%>"><asp:Label ID="FromLabel" runat="server" Font-Size="Small" Text='<%# Eval("UserName")%>'></asp:Label></a></strong> | Date Posted: <asp:Label ID="DateAddedLabel" runat="server" Text='<%# Eval("DateAdded", "{0:MMM dd, yy}")%>'></asp:Label><br /> <asp:Label ID="CommentLabel" runat="server" Text='<%# Eval("Comment")%>'></asp:Label><br /> <br /> </ItemTemplate> </asp:DataList><asp:SqlDataSource ID="SqlDataSource1" runat="server" ConnectionString="<%$ ConnectionStrings:MyDB%>" SelectCommand="SELECT [UserName], [Comment], [DateAdded] FROM [Comments] WHERE ([CL_Id] = @dotnet.itags.org.CL_Id) ORDER BY [DateAdded] DESC"> <SelectParameters> <asp:Parameter DefaultValue="1" Name="CL_Id" Type="String" /> </SelectParameters> </asp:SqlDataSource> </ContentTemplate> </asp:UpdatePanel>

Here is my Code Behind for the save button:

protected void bttnPostComment_Click(object sender, EventArgs e)
{
string flname = Request.QueryString["filename"];
flname = flname.Substring(0, flname.Length - 4);

if (User.Identity.IsAuthenticated)
{
MembershipUser myObject = Membership.GetUser();
string usrid = myObject.ProviderUserKey.ToString();
string usrname = User.Identity.Name;
string cmmnt1 = txtComments.Text;
string connStr = ConfigurationManager.ConnectionStrings["MyDB"].ConnectionString;
SqlConnection cnn = new SqlConnection(connStr);
SqlCommand cmd = new SqlCommand("INSERT INTO Comments (CL_Id, UserId, UserName, Comment) VALUES ('" + flname + "', '" + usrid + "', '" + usrname + "', '" + cmmnt1 +"')", cnn);
cnn.Open();
cmd.ExecuteNonQuery();
cnn.Close();
}
else
{
lblComment.Text = "You need to login to make comments";
}
}

----------

Thanks in advance,

Louis

1. Make UpdatePanel UpdateMode="Conditional"

2. after cnn.close(); write UpdatePanel3.Update()


Thanks siva sakki, I tried your suggestion but it still doesn't work.

What else can I try?

Louis


Updating a DataList with UpdatePanel

On Page_Load event, register DataList control

protected void Page_Load()
{
ScriptManager1.RegisterAsyncPostBackControl(DataList1);

DataList1.DataSource = this.SqlDataSource1;
DataList1.DataBind();
}


Thanks chetan, your suggestion might work. My problem is that I have the ScriptManger1 in the master page.

How can I reference this the way you have specified above?

Thank you,

Louis


I have tried the following to reference the the ScriptManger from content panel code behind:

ScriptManager.GetCurrent(this.Page).RegisterAsyncPostBackControl(DataList1);

is this the correct way of doing it? If it is my UpdatePanel still not updating. I have also removed this two lines:

//DataList1.DataSource = this.SqlDataSource1;
//DataList1.DataBind();

It is giving me this error:

Both DataSource and DataSourceID are defined on 'DataList1'. Remove one definition.

Do I need this two lines for it to work?

I am pulling my hair on this one.

Please help. Thanks again.

Louis


If you go back to the original code you submitted and add DataList1.DataBind() at the end of the button routine, you would probably achieve the results you want.

There is nothing to cause the DataList to rebind after the button event.

If you simply delete the UpdatePanel from the page, your code would not work either. As a rule, if doesn't work without Ajax, it won't work with it. The DataBinding event for the DataList has to run on the postback.


wrayx1 that did the trick.

Thank you soooo much!!!

Louis


Just do withDataList1.DataBind();

Let me know if this helps you


Okay, I have a similar question about updating using DataList. Will someone give me a hand on this. Here's what I have.

1<asp:ScriptManager ID="ScriptManager1" runat="server">2 </asp:ScriptManager>3<%--<asp:UpdatePanel ID="UpdatePanel1" runat="server">4 <ContentTemplate>--%>5 <asp:RadioButtonList ID="RadioButtonList1" runat="server" AutoPostBack="True">6 <asp:ListItem Value="True">Approved</asp:ListItem>7 <asp:ListItem Value="False" Selected="True">Not Approved</asp:ListItem>8 </asp:RadioButtonList>9 <asp:SqlDataSource ID="sqlApproval" runat="server" ConnectionString="<%$ ConnectionStrings:myConnStr%>"10 SelectCommand="SELECT [frstName], [lstName], [dvlID], [mdlName], [mdnName], [degree1], [degree2], [year1], [year2], [sp_frstName], [sp_lstName], [sp_year1], [sp_year2], [sp_mdlName], [sp_mdnName], [sp_degree1], [sp_degree2], [approval] FROM [dvlStory] WHERE ([approval] = @.approval)"11 DeleteCommand="DELETE FROM [dvlStory] WHERE [dvlID] = @.dvlID"12 InsertCommand="INSERT INTO [dvlStory] ([frstName], [lstName], [mdlName], [mdnName], [degree1], [degree2], [year1], [year2], [sp_frstName], [sp_lstName], [sp_year1], [sp_year2], [sp_mdlName], [sp_mdnName], [sp_degree1], [sp_degree2], [approval]) VALUES (@.frstName, @.lstName, @.mdlName, @.mdnName, @.degree1, @.degree2, @.year1, @.year2, @.sp_frstName, @.sp_lstName, @.sp_year1, @.sp_year2, @.sp_mdlName, @.sp_mdnName, @.sp_degree1, @.sp_degree2, @.approval)"13 UpdateCommand="UPDATE [dvlStory] SET [frstName] = @.frstName, [lstName] = @.lstName, [mdlName] = @.mdlName, [mdnName] = @.mdnName, [degree1] = @.degree1, [degree2] = @.degree2, [year1] = @.year1, [year2] = @.year2, [sp_frstName] = @.sp_frstName, [sp_lstName] = @.sp_lstName, [sp_year1] = @.sp_year1, [sp_year2] = @.sp_year2, [sp_mdlName] = @.sp_mdlName, [sp_mdnName] = @.sp_mdnName, [sp_degree1] = @.sp_degree1, [sp_degree2] = @.sp_degree2, [approval] = @.approval WHERE [dvlID] = @.dvlID">14 <SelectParameters>15 <asp:ControlParameter ControlID="RadioButtonList1" Name="approval" PropertyName="SelectedValue"16 Type="Boolean" />17 </SelectParameters>18 <DeleteParameters>19 <asp:Parameter Name="dvlID" Type="Int32" />20 </DeleteParameters>21 <UpdateParameters>22 <asp:Parameter Name="frstName" Type="String" />23 <asp:Parameter Name="lstName" Type="String" />24 <asp:Parameter Name="mdlName" Type="String" />25 <asp:Parameter Name="mdnName" Type="String" />26 <asp:Parameter Name="degree1" Type="String" />27 <asp:Parameter Name="degree2" Type="String" />28 <asp:Parameter Name="year1" Type="Int32" />29 <asp:Parameter Name="year2" Type="Int32" />30 <asp:Parameter Name="sp_frstName" Type="String" />31 <asp:Parameter Name="sp_lstName" Type="String" />32 <asp:Parameter Name="sp_year1" Type="Int32" />33 <asp:Parameter Name="sp_year2" Type="Int32" />34 <asp:Parameter Name="sp_mdlName" Type="String" />35 <asp:Parameter Name="sp_mdnName" Type="String" />36 <asp:Parameter Name="sp_degree1" Type="String" />37 <asp:Parameter Name="sp_degree2" Type="String" />38 <asp:Parameter Name="approval" Type="Boolean" />39 <asp:Parameter Name="dvlID" Type="Int32" />40 </UpdateParameters>41 <InsertParameters>42 <asp:Parameter Name="frstName" Type="String" />43 <asp:Parameter Name="lstName" Type="String" />44 <asp:Parameter Name="mdlName" Type="String" />45 <asp:Parameter Name="mdnName" Type="String" />46 <asp:Parameter Name="degree1" Type="String" />47 <asp:Parameter Name="degree2" Type="String" />48 <asp:Parameter Name="year1" Type="Int32" />49 <asp:Parameter Name="year2" Type="Int32" />50 <asp:Parameter Name="sp_frstName" Type="String" />51 <asp:Parameter Name="sp_lstName" Type="String" />52 <asp:Parameter Name="sp_year1" Type="Int32" />53 <asp:Parameter Name="sp_year2" Type="Int32" />54 <asp:Parameter Name="sp_mdlName" Type="String" />55 <asp:Parameter Name="sp_mdnName" Type="String" />56 <asp:Parameter Name="sp_degree1" Type="String" />57 <asp:Parameter Name="sp_degree2" Type="String" />58 <asp:Parameter Name="approval" Type="Boolean" />59 </InsertParameters>60 </asp:SqlDataSource>61 <br />62 <asp:DataList ID="dltApproval" runat="server" BackColor="White" BorderColor="#999999"63 BorderStyle="None" BorderWidth="1px" CellPadding="3"64 GridLines="Vertical" RepeatColumns="3" RepeatDirection="Horizontal" Width="700px" DataSourceID="sqlApproval">65 <FooterStyle BackColor="#CCCCCC" ForeColor="Black" />66 <SelectedItemStyle BackColor="#008A8C" Font-Bold="True" ForeColor="White" />67 <ItemTemplate>68 <table border="0" cellpadding="2" cellspacing="0">69 <tr>70 <td>71 <asp:Label ID="frstNameLabel" runat="server" Text='<%# loadStory()%>'></asp:Label>72 </td>73 <td>74 <asp:CheckBox ID="chbApproval" runat="server" Checked='<%# Bind("approval")%>' />75 </td>76 </tr>77 </table>78 </ItemTemplate>79 <AlternatingItemStyle BackColor="Gainsboro" />80 <ItemStyle BackColor="#EEEEEE" ForeColor="Black" />81 <HeaderStyle BackColor="#000084" Font-Bold="True" ForeColor="White" />82 </asp:DataList>83<%-- </ContentTemplate>84 </asp:UpdatePanel>--%>85 <table border="0" cellpadding="5" cellspacing="0" width="700">86 <tr>87 <td style="width: 100px; text-align: center">88 <asp:Button ID="btnUpdate" runat="server" OnClick="btnUpdate_Click" Text="Update" /></td>89 <td style="width: 100px; text-align: center">90 <asp:Button ID="btnFinish" runat="server" OnClick="btnFinish_Click" Text="Finish" /></td>91 </tr>92 <>  

And here's the code behind:

1protected void Page_Load(object sender, EventArgs e)2 {34 }5protected string loadStory()6 {7//load the data in here and display to the lable control8return strInfoHolder.ToString() ;9 }10protected void btnUpdate_Click(object sender, EventArgs e)11 {12 sqlApproval.Update();13 dltApproval.DataBind();14 }15protected void btnFinish_Click(object sender, EventArgs e)16 {17 Response.Redirect("~/Admin/");18 }

The problem I have is that it's not updating. At the moment, I disabled the AJAX UpdatePanel to figure out the udpate first. All I wanted is to update the Approval checkbox to the sqlDataSource control. Noticed I used Bind instead of Eval for the checkbox control that way I was hoping that once I called the sqlApproval.Update() method, the approval checkbox will automatically update the database field. However, that is not so. Any help is appreciated.

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