I have a simple radio button list inside a form view:
<asp:RadioButtonList ID="RadioButtonList1" runat="server" SelectedValue='<%# Bind("Answer") %>' Visible="false">
<asp:ListItem Text="Yes" Value="true" ></asp:ListItem>
<asp:ListItem Text="No" Value="false"></asp:ListItem>
</asp:RadioButtonList>
The "Answer" property does not exists, and even though RadioButtonList1 is invisible, it's still being bound to. Why is this? I've tried changing the visibility in various page life-cycle events with no luck.
Any ideas?
Visibility has nothing to do with binding. You would have to remove either the binded property or the button itself for the binding to disappear.
Related
I'm have ASP MultiView for an application form. Inside one of the view I have few radio button as follows--
<div class="row">
<asp:CustomValidator ID="Group1Validator" GroupName="Group1" runat="server"
ValidationGroup="Group1" Display="Dynamic"></asp:CustomValidator>
<asp:RadioButton ID="Group1Yes" runat="server" GroupName="Group1" Text="Yes"/>
<asp:RadioButton ID="Group1No" runat="server" GroupName="Group1" Text="No" />
</div>
Now on the code behind I want to iterate through all the RadioButtons in that page and pull the values to be saved in the DB. I have tried the solution HERE both Loop and LINQ version, but the problem is my RadioButton controls are not directly in the page. Let me elaborate-
First, I have multi view in a page-
Multi view contains views-
And finally inside views I have the RadioButton controls-
Now my goal is the fetch the values of all the RadioButton that are selected which is laid out using the div above.
Any help and guidance will be much appreciated! Thanks!
You must put your RadioButtons as childs of RadioButtonList, then iterate in foreach loop over RadioButtonList items.
Why not use a RadioButtonList
<asp:RadioButtonList ID="RadioButtonList1" runat="server">
<asp:ListItem Text="Yes" Value="1"></asp:ListItem>
<asp:ListItem Text="No" Value="0"></asp:ListItem>
</asp:RadioButtonList>
And then you can get the value in code behind
string value = RadioButtonList1.SelectedValue;
You can also add items to the RadioButtonList in code behind
RadioButtonList1.Items.Insert(0, new ListItem("Yes", "1", true));
RadioButtonList1.Items.Insert(1, new ListItem("No", "0", true));
I have been adding UpdatePanels to my application around the objects that I just want to update.
Example, When I click a button I want a ListBox to update. I would wrap the UpdatePanel around the list box in the html, but when I do this my design goes all over the place.
I am not sure If I'm using AJAX the correct way, as I have seen people adding Triggers but don't know how and where to use them, here is an example of my code:
<asp:ListBox ID="lst_AdminExistingDepartments" runat="server" >
<asp:ListItem Text="Acceptance"></asp:ListItem>
<asp:ListItem Text="Acceptance"></asp:ListItem>
<asp:ListItem Text="Acceptance"></asp:ListItem>
<asp:ListItem Text="Acceptance"></asp:ListItem>
<asp:ListItem Text="Acceptance"></asp:ListItem>
<asp:ListItem Text="Acceptance"></asp:ListItem>
<asp:ListItem Text="Acceptance"></asp:ListItem>
</asp:ListBox>
</div>
<div class="AddEditUpdateDepartment">
<asp:Label ID="lbl_AdminAddEditUpdateDepartments" runat="server" Text="Modify Departments" />
<asp:Label ID="lbl_AdminAddDepartment" runat="server" Text="Add Department" />
<input id="txt_AddDepartment" runat="server" type="text" class="aclass" />
<input id="btn_AddDepartment" runat="server" type="button" class="ButtonAdminPage" value="Add" onserverclick="btn_AddDepartment_ServerClick" />
Here is a ListBox and also a Textbox and a Button. When they click that Button I would want the ListBox to update with the record entered in the TextBox using AJAX?
At the most basic level you need to place the UpdatePanel around all controls being affected by the action. So you need the List, TextBox and Button all inside the UpdatePanel.
Following on from that you have more advanced scenarios where you can have Triggers and multiple UpdatePanels etc. However, it would be best to start with something simple (i.e. everything you need in one UpdatePanel and advance from there.
I have a page that contains a Repeater, which contains server control elements, within an UpdatePanel and while all other controls behave normally, the Drop Down control causes a full postback every time.
<asp:Repeater ID="rpt" runat="server">
<ItemTemplate>
<asp:SomeWorkingControl ID="swc" runat="server" />
<asp:DropDownList ID="ddl" runat="server" OnSelectedIndexChanged="ddl_SelectedIndexChanged" AutoPostBack="true">
<asp:ListItem Text="0" Value="0" />
<asp:ListItem Text="1" Value="1" />
</asp:DropDownList>
</ItemTemplate>
</asp:Repeater>
This is vaugely what my code looks like, the DropDownList control is actually in a UserControl, but the theory is the same.
If I apply an event to SomeWorkingControl then there is an Ajax postback and all is fine.
However, the event associated with the DropDownList causes a full postback! I know usually you would set an Async trigger for the DropDown, but since it is created in a repeater (and therefore I can not know how many there will be) so I don't really see how that could work.
Is there anybody who has experienced this before and knows a workaround perhaps?
Try to change this line:
<asp:DropDownList ID="ddl" runat="server" OnSelectedIndexChanged="ddl_SelectedIndexChanged" AutoPostBack="true">
for:
<asp:DropDownList ID="ddl" runat="server" OnSelectedIndexChanged="ddl_SelectedIndexChanged" AutoPostBack="true" ClientIDMode="AutoID">
Recently I had the same problem and I found out that the ClientIDMode can solve it.
Please have a look here: asp.net ClientIDMode Changes
I have a databound dropdown list on my page. The first value in the selection list is blank. Is there a way that I can change it so that the first selection says "Unassigned" instead of blank? I've tried the following, but it didn't work:
// Insert 'Unassigned' value for artist dropdown
ddlArtists.Items.Insert(0, "Unassigned");
After inserting the above code, the list still appears unchanged, with the first selection value being a blank. Any pointers would be great! Thank you!
EDIT: Here is the code for the dropdown:
<asp:DropDownList ID="ddlArtists" runat="server" Width="130px" TabIndex="5"
OnSelectedIndexChanged="ddlArtists_SelectedIndexChanged"
DataSourceID="sqldsArtist" DataTextField="Name" DataValueField="ID"
OnDataBound="ddl_DataBound"
AutoPostBack="True">
You don't need to do it on the CodeBehind. Just do it like that:
<asp:DropDownList ID="ddlArtists" runat="server" AppendDataBoundItems="true">
<asp:ListItem Text="Unassigned" Value="0" Selected="true" />
</asp:DropDownList>
The AppendDataBoundItems property defines whether the contents of the DropDownList should be cleared out before data binding.
Don't forget to check for a PostBack when you're data binding it, to avoid duplicates.
Set the SelectedIndex property of your DropDownList to 0.
I have a drop down list in UpdatePanel_2, it gets populated when Button_1 is clicked in UpdatePanel_1.
My ddlist markup is,
<asp:DropDownList id="drop1" runat="server" EnableViewState="true" AutoPostBack="true" OnSelectedIndexChanged="Drop1_SelectedIndexChanged" />
then code behind is,
protected void Drop1_SelectedIndexChanged(object sender, EventArgs e)
{ }
I also tried putting AutoPostback=true to my DropDownList, still no success.
I also added triggre to update panel 2 but no gain,
<Triggers>
<asp:AsyncPostbackTrigger ControlID="drop1" EventName="SelectedIndexChanged" />
</Triggers>
I am populating DropDownList using a button not PAGE LOAD METHOD PLEASE READ before answering.
Thanks
Check the data to populate the DropDownList in the Page_Load event and always check IspostBack:
if(!IsPostBack)
{
//DropDownList configuration
}
Use EnableViewState:
<asp:DropDownList ID="ddlAddDepPlans" runat="server" AutoPostBack="true" EnableViewState="true" />
Hope it helps you.
I had the same issue. My problem was that the values of my ListItems were all the same :D
<asp:DropDownList ID="ddlFilterLogins" runat="server" Visible="true" AutoPostBack="true">
<asp:ListItem Value="0" Text="All"></asp:ListItem>
<asp:ListItem Value="0" Text="Some"></asp:ListItem>
<asp:ListItem Value="0" Text="Some more"></asp:ListItem>
</asp:DropDownList>
It should be like this:
<asp:DropDownList ID="ddlFilterLogins" runat="server" Visible="true" AutoPostBack="true">
<asp:ListItem Value="0" Text="All"></asp:ListItem>
<asp:ListItem Value="1" Text="Some"></asp:ListItem>
<asp:ListItem Value="2" Text="Some more"></asp:ListItem>
</asp:DropDownList>
Hope this helps. This might be hard to find sometimes :)
Please, when you initialize it in Page_Load() check if not is postback. If you don't do it, you will always set the default value, and this replaces the value setted in the event.
if(!IsPostBack)
{
//DropDownList configuration
}
You can use Init event instead of SelectIndexChanged.
It worked fine for me.
Hope you got my point.
It was also a wired problem for me. finally It was because of identical listitems in the dropdown as shown below. during development you may use same items just for testing. change them.
<asp:ListItem>Business</asp:ListItem>
<asp:ListItem>Business</asp:ListItem>
<asp:ListItem>Business</asp:ListItem>
<asp:ListItem>Business</asp:ListItem>