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Adding controls to a form dynamically

Posted By:      Posted Date: September 29, 2010    Points: 0   Category :Windows Application

How to add checkboxes at a particular positon in a application dynamically.

That is ,I want to add checkboxs depending on the no of items in a collection and i even want to name it.How can i do it?

Can i get any sample code for it?

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Adding Controls dynamically in the infopath form - A standard Expense Entry scenario



I am having a requirement where I need to create an Expense Report Entry form using Infopath 2010. 

1) The form would have pre-defined columns/Controls like Exp.Type(drop-down) , Details , Location, Amount , Curruncy, Date etc..

2) User can enter/update as many line items as possible by clicking Add/Update/Delete for the each line items. So basically its like adding the same row dynamically.

3) When User Submits, I need to capture this data and post it to SAP where I am using SAP web Services.

Can you please suggest if this is possible in InfoPath form ?

If Yes, how can I achieve this dynamic line items functionality in InfoPath

And how can I read the data using the code so that I can Post it to the WebService? 

Adding carriage returns between 2 dynamically created controls in an HtmlTableCell


The title pretty much explains it. Here is what i'm trying to do...

 Private Sub LoadGrid_CommentsField(ByVal Row As HtmlTableRow, ByVal BookingNumber As String, ByVal CommentsText As String)
  Dim Txt As TextBox
  Dim Cmd As ClickOnceButton.ClickOnceButton

  Txt = New TextBox
  Txt.ID = "txtComment_" & BookingNumber
  Txt.CssClass = "TFAppControls"
  Txt.TextMode = TextBoxMode.MultiLine
  Txt.MaxLength = 500
  Txt.Width = New Unit(95, UnitType.Percentage)
  Txt.Text = CommentsText

  Row.Cells(cComments).InnerHtml &= "<br/>"

  Cmd = New ClickOnceButton.ClickOnceButton
  Cmd.DisableAfterClick = True
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  Cmd.CssClass = "TFAppButtons"
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On the line where i try and update the InnerHtml, i get the following error; "Cannot get inner content of  because the contents are not literal."

this.controls.add - not always adding to parent form

My current code (snippet below) iterates through user info and adds the same custom control to a form based on how many "Meals" (1-6) the user has selected.  It appears that all even # controls (the second, fourth and sixth) are added to the previously added control, rather than the parent form, when I later try to dispose the controls by iterating through this.controls, only 1, 3 and 5 appear, the others appear as children to 1, 3 & 5. I've reduced controls size, etc. to make sure they're not overlapping (if that can force inheritence?) but no luck.  Anyone have suggestions on what to look at or other guidance? public void drawMealPanel(Meal m, int x, int y) { Controls.MealDisplay md = new Controls.MealDisplay(m); md.Name = m.name; md.Tag = m.id.ToString(); md.Left = x; md.Top = y; md.DragDrop += new System.Windows.Forms.DragEventHandler(this.MealView_DragDrop); md.DragEnter += new System.Windows.Forms.DragEventHandler(this.MealView_DragEnter); this.Controls.Add(md); }

Dynamically adding User Controls -- newbie question!

I am new to ASP.NET (coming from ColdFusion, thank goodness I'm away from that!).  And I am have THE hardest time understanding how to work with forms in ASP.NET.  Here's what I am doing:Dynamically add User Controls to a PlaceHolder based on some int value (which currently is passed in a HiddenField).Fire an event if the WebControls inside of the User Control change, then handle that event in the Main Page (i.e. save the input to DB)When the user clicks the "Next/Continue" button, the next controls for the next page are loaded.And I guess maybe I just can't seem to get how things work in ASP.NET, because I am really struggling with the general idea of how ASP.NET flows.  Should I be dynamically loading the controls in Page_Init, or Page_Load?  Or should I load the controls when the buttonclick event is fired?Do I have to add the axCtrl.OnDataChange += new EventHandler(HandleAxControlDataChange); line on Page_Load?  Or should I put this in When I first load the UserControl, I need to initialize some WebControls within the UserContorl.  Is there a way to know if I have loaded new user controls into my placeholder?  I can't use Page.IsPostback, because after the first page, every page is a postback from the buttonclick.Any help for this confused newbie would be GREATLY appreciated!!Here's what I have: pu

Adding controls dynamically


Hi All,
I am creating a questionnaire in a gridview. The questions, answer options and answer control are under CMS. So I am building the questionnaire 'on the fly' adding controls to the page dynamically.

In Page_Load during !Page.IsPostback I bind the question text to the gridview then have another method that iterates through the gridview rows, and adds the controls to a cell eg.gvr.Cells[1].Controls.Add(rbl); The page renders correctly - I see all questions, answers and answer control eg, DropDownList, RadioButtonList, TextBox etc.

The problem is when I try to save the selected options, FindControl cannot find the controls. Even though when I view source I can see all ctrls and ids. I've seen a lot of posts about this issue and CreateChildControl, EnsureChildControl seem to be the route to take. But I don't unserstand how to use them. Can anyone point me to a good example?

And if anyone can explain why it is not working. The page 'looks' to be rendering correctly. Why then are the controls not being found on the postback? Are the controls not being added to the ViewState?


How to set alignments of form controls dynamically.

I have a form containing two panels. In both panels there are two labels and textboxes. I set the 'Center In Form' property of the labels and textboxes to 'Horizontally' and 'Vertically' in design time respectively. But as the form is resizable, when the size of the form is increased or decreased at runtime the controls are no longer center aligned in the panels. How can I handle this problem (provided the main form needs to remain sizable)? Please help.
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Dynamically adding content to page outside of the aspnet form from within a UC


I have a uc which generates a html form  that should auto-submit when the browser loads the page, so I need to add the form to the page before the </body> tag - outside the asp.net form, id like my UC to work without having any requirements on its parent page / masterpage.

i have managed to add a literal inside the body tag by calling the following inside CreateChildControls on the parent page
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however this required the body to have runat="server" and the code to be added to the user control's parent page. ( this also seems to cause the viewstate to be lost after postback)

Is there any way i can append the string to the rendered html inside the body but outside the <form></form> from within the UC code

Incase it makes a difference the UC is being added dynamically to the page.

Dynamically Create Controls in ASP.NET by Using Visual C# .NET

This article demonstrates how to dynamically create a control for an .aspx page. The sample project does the following:
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Dynamically Create Controls in ASP.NET with Visual Basic .NET

This step-by-step article describes how to dynamically create controls for an ASPX Web page.

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dynamically adding sql server columns based on number of files in fileuploader


I want to create a new table to sql database at runtime.  The column names would be "Name", "Date", "Event".  I would also like to have one more column name "Image" but the problem is that since the amount of images will vary, I want the application to count the amount of files in the Multiple fileuploader and then add a image column to the table for the respected amount of files. 

For example if i am uploading 3 files in the multiple fileuploader, the names should be "Name", "Date", "Event", "Image1", "image2", Image3"

I also would like that table name to be name dynamically from the textbox Name when the user enters the information.


I have the following code to make a new table, but I dont know how to name the fields at runtime like previously asked please help!!!


Dim objConn As New SqlConnection("Server=<servername>;uid=<userid>;pwd=<password>;database=master")


Cutting Edge: Adding a Context Menu to ASP.NET Controls


Although the context menu is a common element of most desktop applications, it is still fairly uncommon in Web application names because it doesn't map well to a server-based technology like ASP. NET.

Dino Esposito

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How to dynamically create user controls ?



can you explain how to create user control dynamically in a web form ?When i am creating server controls of user controls are not instantiated and it is not getting initialized .when i am tyying to initialize its properties error occurs tha object instance not created .

Any suggestion ? 

Adding client event handlers to an ASP.NET controls programmatically



I want to add client event handlers to ASP.NET controls (For example: GridView/Button ) programmatically to ASP.NET.

I am aware of "onclick" event handler, so my code would be

GridView1.Attributes.Add("onclick", "JSGridViewFunction()");

Button1.Attributes.Add("onclick", "JSButtonFunction()");

I want to know what are all the event handlers that are available for (or that can be added to)  ASP.NET controls.

For example, I want to add "onsort" event handler to ASP.NET GridView control.

But the following code fails

GridView1.Attributes.Add("onsort", "JSGridViewFunction()");

Please help.


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