Web Forms :: How To Use SelectedIndex On DDL Items After Re-populating List
Jun 23, 2010
I have a Drop Down List that has some items in it, I have a switch set up that will clear and repopulate the drop down list from a sql server db depending on which item is chosen. When the list is repopulated from a database table I want to use an if statement to do something based on which item is chosen. I've tried to use an if statement but no matter what I try, the code checks the if statement for the original items in the drop down list, not the items that repopulated the drop down list.
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 want to set the selectedindex of ddlExceptionNumbers to a Session variable value. I set my debugger just passed the last line of this code segment, and it doesn't change the selectedindex, it's 0. Session["CurrentExceptionID"] has a non-zero positive value.
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.
This is my first web page ever and I can't seem to find the correct way to get the selected index from a dropdown list. I don't need the selected index until the user presses the submit button. I've been testing everything I've found on the subject, but nothing is working.
I don't want the drop-down box to reset when the selection is made, which is what happens if I use postback=true or any selected index changed events. And, I still get an index of 0.
Using MVC2, I want to know how you add the options of a dropdownlist from a database. I have several lookup lists so I will need to do this many times. I'm stuck on part 5 of the MusicStore (which is using MVC3) at this part
[Code]....
Alternatively if someone could recommend an MVC2 tutorial which covers drop lists.
can i do something simular to olUploadedFiles? there are alot of list options in webcontrols and i'm unsure how to use them. I would like to use a for loop to populate olUploadedFiles from a string array in my .cs. something like ...
int i = 0; while (files[i].Length !=0) { olUploadedFiles.add (files[i]);//i'll substring the file names out i++; }
I'm using the same control for both the form submit and the status page(label only mode). I can load the rest of the info i just can't populate the dropdown from the codebehind.
what the problem is that i want to populate drop down list manually
but the thing is i have 3 drop down lists
in first one user will select table name from where the data of 2nd Drop Down list will come
suppose user selected seo then the sql query would be select project_name from dropdownlist1.selecteditem
and this query will show project_name column of seo table in dropdownlist2
then user will select any project name from dropdownlist2 suppose he select salveo so i want that my text box will get populate with project_id of project_name
suppose the project_id of salveo is 123 then automatically in textbox it will enter 123
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 an ajax tab control and on each tab (4) there is a list box. Above the tab control is a button. What the user can do is select a tab, press the button to run the process. Each of the 4 processes does it's magic in the back ground and then dumps messages as it progresses to the list boxes. They work fine if I only run 1 and stay on that tab.
What I want to be able to do is to start a process on a tab, switch to another tab and start the process and be able to go back and forth to each tab to see the progress. Each tab has it's own timer control as well (set to 10 seconds).
I have 3 drop down boxes, created using the HTML select tag. On page load, the first box has a few names. Now, when I click on one of the names in the first box, some more names should appear in the second and when I click on a name in the second box, some more names should appear in the third box. How can I achieve this using AJAX? I have to use ASP.Net and MS SQL Server only. I'm a complete noob to AJAX and I've been educating myself about it, but nothing's working out. I've been looking for the code for close to a week. I looked up w3schools.com, but when I tried that code, it didn't work. Please help me out and please tell me step by step, the things required in order to make it work, and what goes where. I have a deadline that is fast approaching and am at my wit's end trying to make it work.
selecting a few items from a list of thousands. I have an autocomplete field that searches the db, and returns a name/id pair. This is working fine.
The next step is to preserve the selected IDs, and allow the user to remove some if needed. For this, I've been looking at using a select, and was hoping a UI something like that provided by this, but it doesn't work: it allows you to select items that already exist in the select, but doesn't work with a dynamically created select.
The final step is a traditional postback (using a submit button, this is in asp.net webforms) where I'll need to have access to the final list of IDs.
I am trying to assign values I've gathered from a JSON feed to my own type, a class in which I have defined certain fields (properties) to put the JSON elements into, plus elements that are derived from a RegEx pattern matching process. This will then allow me to access the object using LINQ, as I am using a List to hold my objects. There is a foreach loop in my code that loops for each match that my RegEx method finds. I am only interested in the parts of the JSON feed where there is a match. So my own defined class is as such:
//simple field definition class public class TwitterCollection { public string origURL { get; set; } public string txtDesc { get; set; } public string imgURL { get; set; } public string userName { get; set; } public string createdAt { get; set; } }
And then I want to populate List in the RegEx Matches loop:
foreach (Match match in matches) { GroupCollection groups = match.Groups; var tc = new List<TwitterCollection>() { origURL = groups[0].Value.ToString(), txtDesc = res.text, imgUrl = res.profile_image_url, userName = res.from_user_id, createdAt = res.created_at, }; }
The code will then go on to extract and sort the results via Linq to Objects. But compiler won't actually let me create my var tc = new List<TwitterCollection>() because: 'System.Collections.Generic.List' does not contain a definition for 'origURL' ... even though I have defined it. It does not flag an error if I simply write new TwitterCollection but then how do I refer to this in my Linq expression later on??
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;
I'm designing my own custom control that contains a .NET dropdownlist. What I'm wondering is if it is possible to populate my dropdownlist with listitems placed in a placeholder? For example:
This doesn't work because the DropDownList control only allows ListItems as child controls. But, I want to do something similar to this so when the user includes my control on a page, they can do something like this:
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 have a generic List which is populated with an object which has properties like FirstName, Surname etc.
If I bind a gridview to the list with autocompletecolumns = true, the Gridview displays the data in the List.
The code looks like:
[code]....
My question is:
How do I populate the DataKeyNames with the properties (FirstName, Surname) contained in the object that is contained in each element of the Generic List?
Is it possible to select values from a List, where the items contain in a different list aswell?for example;
[Code]....
What I need are all the items from the first list "Items", where the string contains something from the second list "List".So I need something which returns the first 3 items (which contain the term "Item") from the first list.
I am trying to populate table column names into a dropdown list . how can I query using Linq to SQL to just get the list of few Column names ? in a method in DAL which I can use to load in my UI page !!