Web Forms :: Use Dynamically Created Controls Such As A Checkbox List And Fill The Values Dynamically?
Sep 28, 2010
I'm creating an quiz application which queries the database and extracts the questions and choices. I use dynamically created controls such as a checkbox list and fill the values dynamically. How do I do this? Right now I have these functions:
array_random_init(); this creates a 10 element integer array from 1-20 - extract_question(i): this extracts a question indexed at i in DB, I created the controls and set the appropriate text in this function. - validate_question(i); this is called by button_click and validates the question i according to DB.
I understand I have to recreate the controls in Page_init on postback, but what should it look like? Do I need to add "if IsPostBack" in page_init, or do I create the controls in page_init() and reset their properties in page_load when I use extract_question(i)? Also, I cannot seem to clear the selected boxes on postback, I added page directive "enableviewstate=false" but it doesn't work.
Im basically listing a set of facilities in a datagrid. Like so:b Projectorcb Laptopcb TelevisonIn roomview, a check appears where a facility is availble in a room. This part works fine.The user can then edit the facilities, by clicking on the check beside each facility. When the update button is pushed I need to record the value of the checkbox, however I cant get the value of the checkbox.eres my codebehind:
I have created one user control in which I have taken a gridview. Columns of this gridview are getting generated dynamically. (i.e. I read Column name from Xml file) But now I want my first coloumn of this gridview as a checkbox field.
I have a database with some data in. Now I'm trying to show that data on my page whit a ListView.
For each object from the database a ListView will generate a dropdownlist.
I also have a DataPager on my page and this is where the problem occurs.
Each object generated from the database has a field that may look like this example.: 1,2,3.
In my code now I´m trying to split this string of comma character and add new items to my dropdownlist.
This works as long as I do not have DataPager on. But if I choose to view an x number of pages at the time when the page loads, I have value in the dropdownlists, only on my first page.
I am new to asp.net. I am trying to display some data from a database table using dynamic table in my page. I want to add checkboxes to a field in the database and would like to perform several tasks based on the values checked. The checkboxes are tied with the primary key field of the database. Here is the code snipet :
[Code]....
Now I have a button in my page. The functioanlity which I desire is on clicking that button I should be able to extract the values of checked checkboxes and perform some function.
I am creating a project that dynamically creates radiobuttons. So far, i'm done with creating those radiobuttons dynamically. My problem is getting the values from those radiobuttons. To get those values, I need to click the submit button, however it seems that the radiobutton value or the radiobutton itself is lost after I click the submit button.
here are my codes, though not my exact codes, it follows the same logic...
i am desigining an application where i m creating checkBox (not checkBoxList) dynamically. There is one master check box that define group if i click that it should click all subCheck box under it.I am using ajax in my application.i am able to generate check box at runtime but not able to find its event here is the code for creating check box and its event.
//This define master check box
CheckBox MstChk = new CheckBox(); MstChk.ID = Str_Header; MstChk.AutoPostBack = true; MstChk.CheckedChanged += new System.EventHandler(MstChk_CheckedChanged);
[code]...
now problem is here when i click on masterCheckBox i am not able to get Evnet MstChk_CheckedChanged but if call DesignUserPrivilegePnl() in page_init instant of Page_Load i am able to get the event but then i get erro object instatnt not set to an instat of object at foreach (Control Child in Parent.Controls)i am googled but still not get the solution hope you people will guide to overcome my error
however, on the server side (after postback) I can't read them from the Request Object. How do I "mark" them so I can read them at the postback?
protected void DeleteSelection_Click(object sender, ImageClickEventArgs e) { int multiIdsToDelete = Request.Form["multiCheck"]; <-- In the Future will be added to an array so I can do the delete for each row selected. }
I am using asp.net/c# application. In my application, I have a gridview.<asp:GridView id ="gv_QuestionList" runat="server"> </asp:GridView>In Code Behind, I created dynamic textboxes and DropDownLists on RowDataBound.
[Code]....
I have a Save button out side the gridview which stores all the row values into database. when I click the "Save" button, I lost dyanamically ceated controls like textbox,dropdown and values (on postback).How can i get all the dynamically created controls and values after the post back?
I have a website that sales associates access to view account information with clients. S.A's can only view information for accounts that they are tied to. Some clients have more than one account, S.A's can be tied to more than one account, but not all accounts of one client need to be tied to one S.A.
On the account info pages, I have account numbers (dynamically displayed labels) displayed of other accounts that the account client is associated with, which the S.A's can see. I'm modding this so that if the S.A has viewing permissions of any of the other accounts on that list of accounts, that instead of a label being displayed, a button directing them to that account page will display instead. In order for this to work, I have to attach a security function to the button, otherwise the page will blow out on the S.A's.
So I'm running a piece that is displaying a button instead of a label, which is working fine. My problem is when I try to attach the security event to the dynamically displayed buttons. It seems that the page just posts back and doesn't execute my code at all.
On my Page_Load, I'm running this after the buttons and labels are displayed:
For x = 0 to tblAccountList.Rows.Count - 1 'use a try to target the button, use catch to handle if it's instead a label, only one cell per row. Try Dim accountLink as Button = tblAccountList.Rows(x).Controls(0) Addhandler accountLink.Click, AddressOf Me.PermissionViewCheck Catch ex as InvalidCastException Continue For End Try Next
I don't have any code checking for postbacks or anything like that, but the "PermissionViewCheck" event never fires and just reposts the page.
now i am facing the problem to validate the checkboxlist is displaying dynamically, acutally at my present page i am doing the checkboxlist which is controled by another check box for the checkboxlist items for select and deselect, now i need to handle the validation for this checkboxlist for null value
I'm new to web dev and c# so please bare with me. I am trying to create a dynamic gridview in a web form for users to to answer questions with (code below).
The dificulty im having is that i am nesting a dropdwonlist in the gridview and want to be able to dynamically set the list values based on parameters (of the row they are on). These values are in the main dataset for the gridview as each row represents a questionid and question text and then a ddl for the criteria...
I just don't know how to set the values for the dropdown all the code so far is below... just need to be able to populate the dropdowns with the relevant values.
I have created a stored proc to return the different criteria based on the questionid and questionGroupid which is the dataset that populates the other fields in the gridview: dbo.usp_QuestionCriteria @QuestionGroupId, @QuestionId
I have added this as a tableadapter called criteriaTableAdapter in a xsd file as well using the wizard... not sure if this is the right option though or just use the same method as i have for the other stored procedure as in the code below:
[CODE
]using System; using System.Data; using System.Configuration; using System.Web; using System.Web.Security; using System.Web.UI; using System.Web.UI.WebControls; using System.Web.UI.WebControls.WebParts; using System.Web.UI.HtmlControls; using System.Data.SqlClient; public partial class _Default : System.Web.UI.Page { protected void Page_Load(object sender, EventArgs e) { SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["Sql"].ConnectionString); con.Open(); SqlCommand com = new SqlCommand("usp_QuestionGroupDS", con); com.CommandType = CommandType.StoredProcedure; SqlDataAdapter ada = new SqlDataAdapter(com); DataSet ds = new DataSet(); ada.Fill(ds); for (int i = 0; i < ds.Tables.Count; i++) { if (ds.Tables[i].Rows.Count > 0) { GridView gvDynamicQuestion = new GridView(); gvDynamicQuestion.Width = Unit.Pixel(700); gvDynamicQuestion.BorderWidth = Unit.Pixel(0); gvDynamicQuestion.Caption = "<div id="nifty" class="QuestionGroup"> <b class="rtop"><b class="r1"></b><b class="r2"></b><b class="r3"></b><b class="r4"></b></b>" + ds.Tables[i].Rows[0]["Category"].ToString() + " Questions<b class="rbottom"><b class="r4"></b><b class="r3"></b><b class="r2"></b><b class="r1"></b></b></div>"; gvDynamicQuestion.AutoGenerateColumns = false; gvDynamicQuestion.ShowFooter = true; TemplateField tf = null; tf = new TemplateField(); tf.HeaderTemplate = new DynamicGridViewTextTemplate("QuestionId", DataControlRowType.Header); tf.ItemTemplate = new DynamicGridViewTextTemplate("QuestionId", DataControlRowType.DataRow); tf.FooterTemplate = new DynamicGridViewTextTemplate(DataControlRowType.Footer, ds.Tables[i].Rows.Count); gvDynamicQuestion.Columns.Add(tf); tf = new TemplateField(); tf.HeaderTemplate = new DynamicGridViewTextTemplate("Question", DataControlRowType.Header); tf.ItemTemplate = new DynamicGridViewTextTemplate("Question", DataControlRowType.DataRow); gvDynamicQuestion.Columns.Add(tf); tf = new TemplateField(); tf.HeaderText = "Criteria"; tf.HeaderTemplate = new DynamicGridViewTextTemplate("Criteria", DataControlRowType.Header); tf.ItemTemplate = new DynamicGridViewDDLTemplate(); gvDynamicQuestion.Columns.Add(tf); ////tf = new TemplateField(); ////tf.HeaderText = "Criteria"; ////tf.ItemTemplate = new DynamicGridViewDDLTemplate(); ////gvDynamicQuestion.Columns.Add(tf); gvDynamicQuestion.DataSource = ds.Tables[i]; gvDynamicQuestion.DataBind(); phDynamicGridHolder.Controls.Add(gvDynamicQuestion); } } } protected void DynamicGrid_RowDataBound(object sender, GridViewRowEventArgs e) { if (e.Row.RowType == DataControlRowType.Footer) { // } } } public class DynamicGridViewTextTemplate : ITemplate { string _ColName; DataControlRowType _rowType; int _Count; public DynamicGridViewTextTemplate(string ColName, DataControlRowType RowType) { _ColName = ColName; _rowType = RowType; } public DynamicGridViewTextTemplate(DataControlRowType RowType, int QuestionCount) { _rowType = RowType; _Count = QuestionCount; } public void InstantiateIn(System.Web.UI.Control container) { switch (_rowType) { case DataControlRowType.Header: Literal lc = new Literal(); lc.Text = "<b>" + _ColName + "</b>"; container.Controls.Add(lc); break; case DataControlRowType.DataRow: Label lbl = new Label(); lbl.DataBinding += new EventHandler(this.lbl_DataBind); container.Controls.Add(lbl); break; case DataControlRowType.Footer: Literal flc = new Literal(); flc.Text = "<b>Total No of Questions:" + _Count + "</b>"; container.Controls.Add(flc); break; default: break; } } private void lbl_DataBind(Object sender, EventArgs e) { Label lbl = (Label)sender; GridViewRow row = (GridViewRow)lbl.NamingContainer; lbl.Text =DataBinder.Eval(row.DataItem, _ColName).ToString(); } } public class DynamicGridViewDDLTemplate : ITemplate { // Implementation of ITemplate public void InstantiateIn(System.Web.UI.Control container) { // Create a DDL DropDownList ddl = new DropDownList(); //Attach method to delegate ddl.DataBinding += new System.EventHandler(this.ddl_DataBind); container.Controls.Add(ddl); } //Method that responds to the DataBinding event private void ddl_DataBind(object sender, System.EventArgs e) { //DropDownList ddl = (DropDownList)sender; //DataGridItem container = (DataGridItem)ddl.NamingContainer; //ddl.Data.Checked = [Data binding expression]; } }
I have a Webcontrol, that I create completely dynamically and it contains radiobuttonList. How can I acces this radibuttonlist values, on pages where I register this control?
public class MyControl: WebControl pnContainer = new Panel(); rbl = new RadioButtonList(); liResume = new ListItem("Resume", "Resume"); liReopen = new ListItem("ReOpen", "ReOpen"); rbl.Items.Add(liResume); rbl.Items.Add(liReopen); pnContainer.Controls.Add(lblReOpenTitle); pnContainer.Controls.Add(rbl); this.Controls.Add(pnContainer);
Im dynamically creating several dropdowns onclick of a button... but the dropdown returns null when im trying to get the values on submitting the form... i read tat during postback all dynamically created controls will be lost... s there a way to register the controls... i want to access the item selected in the dropdown .... expecting a positive reply...
Does anyone know how to pass values from adynamically created gridview checkboxes to a crystal report?Is it possible? I am using asp.net, vb.net and mssql. Here's my grid minus a few boundfields:
I am using cascading dropdown list where the no of dropdowns is created dynamically on the page. The cascading drop downs are contained in a User Control. I need to call a method from the Parent page which will be executed when the values in one of the dropdowns change. The server side event is not firing as I have set AutoPostback property for the dropdownlists to be false. How can i make the Page event fired from the Selected index changed of the dropdowns keeping the autopostback property to be set as false.
after the user login , i need to assign this use name as a global varliable, and then i want to select from a table in the sql server that have select first_name,last_name from dependincies where user id = global_value and then to add the first name and last name , to a list will should have different values according to the global varible values. how i can do this for my mvc project.
I have a tree view with checkboxes for leaf nodes. If i click on checkboxes, I am creating some html controls dynamically. And in other static button click event I need to get an ID's of those dynamically created controls.
I need to create web controls (e.g. label etc) dynamically.The problem is that for example,
on my onload event, I create a label. The text of the label is read from one line of a xml file.
But sometimes the text should be like " Messages (4)", in which the message count is something not generic and need some logic to calculate. I tried to put things like "Message (<#% MessageCount %>) " in my xml file, but the displayed text label is:
Message (<#% MessageCount %>) instead of Message (4 ).
I was looking through my transcender exam kit for 70-562 and they say load dynamically created controls in the loadviewstateEvent. This should be CreateChildControls() instead, no?