Web Forms :: Cascading Drop Down Control & DataSet Using MS Access
May 14, 2010
I am creating a cascading drop down control for use with some drop down lists. They are filled using datasets which connect to a MS Access database. The first dataset was no problem however now I need to create the second which contains a where clause using a passed parameter (ie the selected value from the first drop down). In examples I have seen on the web the @ symbol is used eg WHERE fubar = @varname
When I try to execute this in the query builder in VS2008 I get two errors:
Error in WHERE clause near '@'. Unable to parse query text.
Followed by:
Executed SQL Statement: SELECT DISTINCT tbl_frame.frame_name, tbl_product.frame, tbl_product.model
FROM (tbl_product INNER JOIN
tbl_frame ON tbl_product.frame = tbl_frame.frame_id)
WHERE(tbl_product.model = @model)
Error Source: Microsoft JET Database Engine
Error Message: No value given for one or more required parameters.
It never promts for a variable. If I change the query to be something like WHERE tbl_product.model = 7 it works.
How can I have 2 Cascading Drop Down Lists for the same Drop Down List?here is my problemi have 3 drop down lists read from database1- Schools List 2- Classes List3- Teachers ListEvery School will have more than 1 Class and more than 1 TeacherWhat I want is when user select a School from Schools Drop Down List then BOTH (Classes and Teachers) should be refreshed based on the School Drop Down List
i am using SQL table to cascading 3 drop down list. this is search fields for cars by manifacture, model and year. the 2 first ddl has autopostback and AppendDataBoundItems (true) i want the user will select the facture first, then the 2th ddl will display the models of that manifacture and then the year. for the first time its working good, but when i change the manifacture for the second time, in the model i have the new values + the old values, and go on and on, if i select diffrent facture the model ddl have now values of 3 diffrent manifacture,
I am trying to use a cascading drop-down for data entry. However, I'm having problems because I need to set the value of the drop-downs when I load the screen. I use a stored procedure to retrieve the values from my database, and then set the drop downs in my code-behind. Then the web service kicks in and wipes them out. :( How can I set these values and utilize the cascading drop down control?
my one table consists of fields (id, flying from, flying to). thus i have one drop down for flying from and another drop down for flying to. i'm hoping to cascade them so 2nd drop down values are dependant on the values from 1st drop down. is it possible to do this using a single table? or must i use two tables and link the id's from both? and do i write anyting in the SelectedIndexChange event? the sqldatasource code looks like this:Flying From:
how do i create a cascading drop-down list without using ajax controls...i am using queries and the language i am using is C# I have a client and a project database....when i choose a client name in the dropdownlist....only the project names associated with that client should appear in the next dropdownlist
I have 3 drop boxes: 1.) Choose Operation 2.) Choose Site 3.) Choose Area. All three of them are linked to an SQL server database which has 3 tables following the same heiarchy of order. I.e. Areas belong to a Site and Sites belong to an operation. And there can only be one operation per site, or one site per area.
First you select an operation, then the page auto postbacks to filter the sites. Then you pick a site and again it autopostbacks to filter the areas. The issue I am having is that when an associated operation has no sites underneight it, and therefore no areas under that, the previous values that were in the boxes are displayed and the user can't click on the boxes anymore. I think this is kind of cheap looking and would like a way to make it so the boxes are clear (i.e. nothin in them). Is there anyway to check if they are going to freeze like that and assign them blank values?
I am using 2 cascading drop down lists in my website. When i test my app on localhost both work perfectly. But after uploading my webapp on the hosting server i receive the following error :
I have several cascading drop down in my website which work fine. The problem is that i know need to use cascading drop down in a modal popup. The first list is populated but the subsequent lists are not being populated.
I am using the AJAX Cascading drop down list but want to add event validation e.g. the compare validators.
As the cascading drop down list requires the page event validation to be disabled what is the best way to do the validation?
Validation Attempt: I have tried to use a custom validator which calls a Javascript function but it doesnt seem to be picking up the control. I get the following error Microsoft JScript runtime error: Object required
function ValidateCostCentCat(source, arguments) { var countryList = document.getElementById("ddlCategory"); if (null != countryList) { var iValue = countryList.options[countryList.selectedIndex].value; if (iValue == "Select Category") { arguments.IsValid = true; } else { arguments.IsValid = false; } } }
The mark-up for the custom validator is
<asp:CustomValidator ID="valcustCategory" runat="server" CssClass="error" Display="Dynamic" ValidationGroup="DirectHire" ClientValidationFunction="ValidateCostCentCat" ErrorMessage="Please select a Cost Centre Category from the drop down list provided.">!</asp:CustomValidator>
Does anyone know if it is possible to have Cascading DropDown Lists which are based on the selected value of more than a single list. Example - I have four tables in a database as follows:
Product PartA PartB PartC
The items in Product are made up by one record from each of the other three tables (PartA + PartB + PartC = Product). What I wish to do is have 3 Cascading DropDown lists which refer to the three individual parts which can be used to select items fromt he Product table.
The first two work no problem but when it comes to the third the list is condition on only items which have the selects of both the first two lists.
I have a page that has a cascading drop down. It works perfectly when I start with an empty page and populate data to save a new row in a db table. However, when I try to load an existing row to the page, the parent is populated, but the child and cdd are not populated. During the load, I set the ccd.selectedvalue to a valid value, but by the time the page is rendered, there is no selection. I am sure it is something simple, but just don't see it.
I have a problem with 3 cascading drop downs. They are on a content page, so I have a Master Page as well. They work just fine but once the user saves the data and then comes back to the same page, I would like to show them what was previously saved. How can I pre-select items in the drop downs that I get from my SQL server db? I tried jquery, javascript, vb code behind and no luck so far. I'm sure i'm doing something wrong. Here is my code:
I've been trying to send my webservice a contextkey for the first drop down. When I debug the webservice, and I manually enter a context key, i get the correct values back with the value that equals my context key having <isDefaultValue>True</isDefaultValue>.
Aspx page:
[Code]....
WebService (part of it that gets data for my first drop down):
[Code]....
[Code]....
Javascript (tried to set the context key here)[Code]....
I have 2 dropdownlists, the second (department) cascades from the first (division). I use a jquery script to update the second drop down list. When the user clicks submit, the underlying model is updated, apart from the new value for department. 2 ideas I have for fixing this are; a) Generate a postback. Prefer not to do this because of bad user experience. b) With a JQuery change event, make a call to server side and set a ViewData variable that I can use to update the field in the model later.
However there must be a better way. This is the view;
I'm seeking to develop Web page that has multiple Drop Down List (3 controls) bind with my database and these controls support AJAX and access my database using LINQ
e.g, when I select one of the control name : Class, then It should access the database then, display the department in this class in the next Drop Dawn List in the next control - ALL this without PostPacking this page and access the my database using LINQ.
I seem to be having a problem loading a gridview using 2 cascading drop down lists. Before I implemented the Ajax cascading drop down list extenders and I just had regular drop down list the gridview that is supposed to load when users choose the appropriate data from the 2 drop down list appears when the submit button was triggered.
[Code]....
When the button event is triggered it looks for the specific value in the second drop down list and calls a specific stored procedure to load the gridview. Now after implementing the cascading drop down lists the page just posts back - there are no errors whatsoever.
I am new to Ajax in general but I have a series of cascading drop down lists that are working fine. I'm using them on a form that I want to be able to either add a new row of data to the database or edit an existing one. I have the insert a new row working but editing an existing one is a bit trickier. The drop down lists are only part of the form but I would like to be able to query for a row id and set their values. Right now I'm querying for a row of data and populating the form with its values on page load and all of the fields work except for the drop down lists. I assume that this is because when the page is loading the web methods haven't run yet to populate the cascading drop downs. Therefore I can't set the selected value because there aren't any values yet. So therefore I'm pretty sure I need to do this from a web method so that it runs after the lists are populated or while the lists are populating but I don't know how.
I am currently building a web site and I utilize cascading drop down lists. I am having difficulty clearing two of my drop downs. The application is utilizing Visual Basis. Here is what I found through my research but they are not resetting my drop downs after a post back:
i followed this tut http://www.ajaxprojects.com/ajax/tutorialdetails.php?itemid=554 for cascading drop downs, but i changed the sql connections for my linq datasource. VS2010 is showing no errors in my code and the page loads fine too, but the two drop down lists are emptycan anyone scan there eyes over it and see if theres any reason why it shouldnt be working?my code is the same as the tuts apart from it uses LINQ instead of SQL
