Update Panel - Populating Dropdown List From Database
Mar 25, 2011
I have a ASP.NET AJAX Autocomplete Textbox and Two other dropdownlist in a Update Panel. On selection of an item in Autocomplete Textbox, I want to populate Dropdown list from Database.
I'm trying to progam a strongly typed "Create" view using MVC 3 and razor. I want the user to be able to select a customer from a dropdown list (I populated this from my database using ViewBag in the controller). When the user has selected a customer I want a separate dropdown list to generate a list of dogs belonging to that customer related by the customerID in the database. The create button on the form will then take both of these values along with the the other fields and save it to the database.
I build a webpage to edit the data entry, all the textbox wroks fine. However when I update the value originally took in using dropdown list , I get error and couldn't get correct update.
I am running into some additional difficulties with dropdown lists, and I'm hoping you can correct my thinking.
I have a table populated with items; ITEM_ID, ITEM_NAME, ITEM_COST.
Here is my code:
[Code]....
With this code I get this error: DataBinding: 'ITEM' does not contain a property with the name '2'.
If I remove the assignment of DataSource to c1, the dropdown generates this error: 'DropDownList3' has a SelectedValue which is invalid because it does not exist in the list of items.
Parameter name: value
How should I code this so that the user is presented with a list of ITEM_NAMES, and that the ITEM_ID is stored in the value field so I can use it when the selection event is fired? I know I could databind the source directly to the dropdown list, but I am trying to understand the behind the scenes working of a dropdown list object.
I am populating a page with controls reading properties of a class using reflection. If the property type is 'String' I will add a text-box. If the property type is enum I am adding a dropdownlist. Now I have to populate the dropdown options with enums. How can this be done?
Both the enum definition class(Assignment) and the class(classOne) using which I am populating the page with controls are in the same Namespace(MySolution.Data). While looping through classOne properties when the property name is 'SkillLevel' I will have to go to assignment class get the members of enum SkillLevelEnum and populate the dropdown.
Same needs to be done for other dropdowns also.
My Code:
namespace MySolution.Data { public class classOne : MyAdapter { private string _Model;
On my website, registered users can make a profile about themselves suchas name, Favoirite color, hobbies, etcI have a DataTable called User which hold this information.also there are other datatables for Hobbies and Colors which list all possible options.To let the user update their choices I have a FormView in Edit mode on the aspx page whichis binded to the UserTable with a GetProfileByUserId Method and objectdatasource.
Within the formview, i have added drop down lists that are binded to the hobbies and Colors tables so they can edit their previous selection.On clicking Uodate update formview calls an Update Method that adds new selections to the User databaseNow I have two questionsIs it possible to show in the dropdown list the selected value that the User has already made?If the user only changes hobbies and not colors when they click update will a null value be passed into the data table for colors that replaces their previous selection?
I have a dropdown control that has a list of names in it called PlayerNameDropDownList_Insert and a textBox called PlayerName.
When I select a name from the dropdown it populates the textbox correctly.However, when the page opens the first name is selected in the dropdown but nothing in the textbox. How can I get the textbox to populate with the value of the dropdown at pageload?
I have a page with several panels. panel1 has a drop down list to select client. panel2 has two drop down lists to select facility1 and facility2. I want panel 2 to be disabled (both facility1 and facility2 drop downs disabled) until a selection has been made in panel1 drop down list. when a client is selected from dropdownlist1, I want to enable both dropdown list2 and 3 in panel2.
I have an ajax modal popup extender in update panel. The modal popup extender has a label, checkbox and a dropdown list. When i open the popup first time (i.e Page_load) and select something and click on ok the data is populated correctly in another grid. If i open the popup second time and select some data and click on ok it is populating the grid with the current selected data as well as previously selected data.
I wanted to use using database to populated the dropdownbut i am getting error as type or list space cannot be foundat ListCountry GetCountriesas its defined staticthe web methood code is in the same aspx.cs pagehow culd i use it if a different webmethod page .asmx is created
The subject is explanatory, but here are some details:
I want to update a repeater when SelectedIndex value changes for a dropdown list. The problem is Nothing happens.
My aspx page is present in a nested master page. and neither autopostback works nor update panel. i have set the AsyncPostBack trigger on SelectedIndexChange event.
Please let me know what am i doing wrong or what am i missing.
PS: I have never worked on ajax before so I might have overlooked something.
I have found an odd bug in my application. I have a dropdown status which is bound to my gridview. On selecting a status from the dropdown the selectedindex then fires and binds the results to the gridview.Now the strange behaviour in firefox and not IE:If I have a dropdown open and an ajax update fires on my gridview the option is selected from the dropdown (just by hovering my mouse over it rather than selecting it) and the results bound to the gridview. This does not happen in ie as you should have to physically select an item from the dropdown rather than firefox selecting it for you because you happened to hover over an option when the update event fires.
I am a complete newcomer to ASP.NET. However in the few weeks I have been playing with it I have got pretty far and have mastered things like stored procedures, gridviews, formviews and templates.I have a dropdown box which is populated from SQLDataSource1
I have a second dropdown box which is populated from SQLDataSource2, but i need the query feeding this to be dependent on what was selected in the first dropdown box. I assumed it would simply be a case of modifying the select statement on SQLDataSource2 using the SelectedIndexChanged event on the first DropDownList to update the second SQL source, but I cannot work out for the life of me how to do it. Pretty much all of the code I have is ASP.
can i do this purely in ASP rather than using VB behind the scenes or do I need to use VB? I am pretty comfortable with vb.net but one of the other issues I have is referencing an ASP object from VB... so for instance if I had a text box in ASP, how can I read or change the properties of this object from VB?
I am using cascading dropdown, model popup and update panel in my page.
my all drop down are in update panel. now i am retrieving values from the database through data reader and assign value of respective data to the respective control. but control (drop down list) shows "--select--" and not the retrieve value i.e. "Hospital"
I was trying to implement a dynamic update of a dropdown list in an ASP.NET.MVC2 RC 2 view. My code didn't work. So, in order to verify my approach, I resorted to a published code, which supposedly should be correct: In the View:
<%= Html.DropDownList("Numbers",(IEnumerable<SelectListItem>)ViewData["Services"]) %> <select id="Select1"> </select> <input type="button" id="Button1" value="Fill By Array" /> <script language="javascript" type="text/javascript"> $(function() { $("#Button1").click(function(e) { e.preventDefault(); var data = []; $.getJSON("/Home/GetListViaJson", null, function(data) { data = $.map(data, function(item, a) { return "<option value=" + item.Value + ">" + item.Text + "</option>"; }); $("#Select1").html(data.join("")); }); }); }); </script> In the Controller: [HandleError] public class HomeController : Controller { public ActionResult Index() { //ViewData["Message"] = "Welcome to ASP.NET MVC!"; ViewData["Numbers"] = GenerateNumbers(); return View("Index"); } [AcceptVerbs(HttpVerbs.Get)] public JsonResult GetListViaJson() { return Json(GenerateNumbers()); } private static List<SelectListItem> GenerateNumbers() { var numbers = (from p in Enumerable.Range(0, 20) select new SelectListItem { Text = p.ToString(), Value = p.ToString() }); return numbers.ToList(); } public ActionResult About() { return View(); } }
The Html.DropDownList was correctly populated on PageLoad() event. But the GetListViaJson() action method, when called on the button event, did not update the "Select1" element. how to solve this update problem.
I'm new in asp.net and javascript. I got a problem.
I have a repeater which contains dropdown list in it.
The items in the dropdown list are all the same at fist.
But if i select a item in one dropdown, then the selected item will be deleted in the other dropdown list.
For example
A, B, C, D,E are the five items in dropdown list, and repeater has three lines.
If A is selected in the dropdown list in the first line of repeater, then the dropdown list in the other lines will only have four items to select, they are B, C, D, E.
If then D is selected in the dropdown list in the third line of repeater, then the dropdown list in the second line will only have B, C, E to choose.
I can do this in csharp code, how can i do it in .aspx page?
I am using Visual Studio 2008 and created a simple ASPX page with two drop downs in it. I am using the Update Panel so that when any item is seleted in drop down 1 the second drop down selected item will change accordingly.
I was hoping the update panel will not fix the page refreshing but I am not sure what is wrong since I still see the Page refresh.
I am stuck at this point "Displaying a dropdown list of Categories with a --None -- Option. I want the gridview control to display 2 dropdown list one in read-only mode and the other in edit mode. When a record is in read-only mode, the dropdownlist's enabled property will be set to false."When it's on a read-only mode, it doesn't display the selected Category. it shows but the "No Category". When i click on edit to edit or change category, it doesn't display the selected category.
The example is given below( I am reading the book Sams Teach yourself ASP.NET 2.0 by Scott Mitchell. page 628)
<asp:Label ID="UserIdValue" runat="server" Visible="False"></asp:Label> <asp:SqlDataSource ID="picturesDataSource" runat="server" ConnectionString="<%$ ConnectionStrings:ConnectionString %>" SelectCommand="SELECT * FROM [Pictures] WHERE ([UserId] = @UserId) ORDER BY [UploadedOn] DESC" DeleteCommand="DELETE FROM [Pictures] WHERE [PictureID] = @PictureID" InsertCommand="INSERT INTO [Pictures] ([UserId], [CategoryID], [Title], [Description], [UploadedOn]) VALUES (@UserId, @CategoryID, @Title, @Description, @UploadedOn)" UpdateCommand="UPDATE [Pictures] SET [UserId] = @UserId, [CategoryID] = @CategoryID, [Title] = @Title, [Description] = @Description, [UploadedOn] = @UploadedOn WHERE [PictureID] = @PictureID"> <DeleteParameters> <asp:Parameter Name="PictureID" Type="Int32" /> </DeleteParameters> <InsertParameters> <asp:Parameter Name="UserId" /> <asp:Parameter Name="CategoryID" Type="Int32" /> <asp:Parameter Name="Title" Type="String" /> <asp:Parameter Name="Description" Type="String" /> <asp:Parameter Name="UploadedOn" Type="DateTime" /> </InsertParameters> <SelectParameters> <asp:ControlParameter ControlID="UserIdValue" Name="UserId" PropertyName="Text"/> </SelectParameters> <UpdateParameters> <asp:Parameter Name="UserId"/> <asp:Parameter Name="CategoryID" Type="Int32" /> <asp:Parameter Name="Title" Type="String" /> <asp:Parameter Name="Description" Type="String" /> <asp:Parameter Name="UploadedOn" Type="DateTime" /> <asp:Parameter Name="PictureID" Type="Int32" /> </UpdateParameters> </asp:SqlDataSource> <br /> <asp:SqlDataSource ID="categoriesDataSource" runat="server" ConnectionString="<%$ ConnectionStrings:ConnectionString %>" SelectCommand="SELECT [CategoryID], [Name] FROM [Categories] WHERE ([UserId] = @UserId)"> <SelectParameters> <asp:ControlParameter ControlID="UserIdValue" Name="UserId" PropertyName="Text" /> </SelectParameters> </asp:SqlDataSource> <br /> <asp:SqlDataSource ID="maxPictureIDDataSource" runat="server" ConnectionString="<%$ ConnectionStrings:ConnectionString %>" SelectCommand="SELECT MAX(PictureID) FROM Pictures WHERE UserId = @UserId"> <SelectParameters> <asp:ControlParameter ControlID="UserIdValue" Name="UserId" PropertyName="Text" /> </SelectParameters> </asp:SqlDataSource> <br /> <asp:Label ID="cannotUploadImageMessage" runat="server" Text="The photo could not be added to your album either because you did not specify a file to upload or the file specified was not a JPEG image with the file extension .JPG"></asp:Label> <br /> <asp:DetailsView ID="dvPictureInsert" runat="server" DataSourceID="PicturesDataSource" Height="50px" Width="125px" AutoGenerateRows="False" CellPadding="4" DataKeyNames="PictureID" DefaultMode="Insert" ForeColor="#333333" GridLines="None"> <AlternatingRowStyle BackColor="White" /> <CommandRowStyle BackColor="#D1DDF1" Font-Bold="True" /> <EditRowStyle BackColor="#2461BF" /> <FieldHeaderStyle BackColor="#DEE8F5" Font-Bold="True" /> <Fields> <asp:TemplateField HeaderText="Picture"> <InsertItemTemplate> <asp:FileUpload ID="imageUpload" runat="server" /> <asp:RequiredFieldValidator ID="RequiredFieldValidator3" runat="server" ControlToValidate="imageUpload" Display="Dynamic" ErrorMessage="There was no file selected" ValidationGroup="PictureAdd"></asp:RequiredFieldValidator> </InsertItemTemplate> </asp:TemplateField> <asp:TemplateField HeaderText="Category" SortExpression="CategoryID"> <EditItemTemplate> <asp:TextBox ID="TextBox1" runat="server" Text='<%# Bind("CategoryID") %>'></asp:TextBox> </EditItemTemplate> <InsertItemTemplate> <asp:DropDownList ID="pictureCategory" DataSourceID="categoriesDataSource" runat="server" DataTextField="Name" DataValueField="CategoryID" SelectedValue='<%# Bind("CategoryID") %>' Visible='<%# Bind("CategoryID") %>' AppendDataBoundItems="True"> <asp:ListItem Selected="True" Value="">-- Select Category --</asp:ListItem> </asp:DropDownList> </InsertItemTemplate> <ItemTemplate> <asp:Label ID="Label1" runat="server" Text='<%# Bind("CategoryID") %>'></asp:Label> </ItemTemplate> </asp:TemplateField> <asp:TemplateField HeaderText="Title" SortExpression="Title"> <EditItemTemplate> <asp:TextBox ID="TextBox2" runat="server" Text='<%# Bind("Title") %>'></asp:TextBox> </EditItemTemplate> <InsertItemTemplate> <asp:TextBox ID="TextBox1" runat="server" Text='<%# Bind("Title") %>'></asp:TextBox> <asp:RequiredFieldValidator ID="RequiredFieldValidator1" runat="server" ControlToValidate="TextBox1" Display="Dynamic" ErrorMessage="you must provide a name for the title" ValidationGroup="PictureAdd"></asp:RequiredFieldValidator> </InsertItemTemplate> <ItemTemplate> <asp:Label ID="Label2" runat="server" Text='<%# Bind("Title") %>'></asp:Label> </ItemTemplate> </asp:TemplateField> <asp:TemplateField HeaderText="Description" SortExpression="Description"> <EditItemTemplate> <asp:TextBox ID="TextBox3" runat="server" Text='<%# Bind("Description") %>'></asp:TextBox> </EditItemTemplate> <InsertItemTemplate> <asp:TextBox ID="TextBox2" runat="server" Text='<%# Bind("Description") %>'
I have a user control in a master page with two drop down lists. When the user selects an item out of either ddl, I want to load a specific user control inside an update panel on the content page. I can't figure out how to get the user control to trigger the update panel.