Web Forms :: Load The Dynamically Added HTML Controls During The Post Backs Without Loosing Their States?
Mar 5, 2010
Can any one let me know "How to load the dynamcially added HTML Controls(Controls added using javascript) during the postbacks without loosing their values?
This is what i am trying to do with asp.net updatepanel.i have button and a panel inside my updatepanel. when the button inside the updatepanel gets clicked i want to dynamically add new controls such as LinkButtons to my panel1 without full post back. Now when the dynamically added controls gets clicked it causes a full post pack and also not calling "LinkButton1_Click" event. i am sure i am doing something wrong here.
How to maintain view state for the dynamically added html controls to a table using javascript(Below is the javascript which I am using to add HTML Controls Dynamically"). Because during the postbacks if I found any error while validating the data present in the dynamically added html controls, the controls are loosing their state and again I need to start adding rows and add data.
I have a page with a table and two button with the names (Submit and Add Rows) When I click on Add Row a new row will be added to a page(This is achieved using javascript), when I click on submit button I will be doing server side validation. If I found any error the error will be displayed on the page. During this process the controls which were added by me were loosing its state. As a result I need to add the rows once again and need to fill the data and click on submit button. Can any one let me know how to avoid this and see that the controls donot loose their states. So that there is no need for me to create rows once again if any validation fails on the server side.
I have three identical procedures that are all used to open the contents of a GridView into Excel. One was working fine but the other two were getting a 'RegisterForEventValidation can only be called during Render();' error when attempting to run the form.RenderControl(html) command. The only difference I saw was that the one that was working had the allowsorting value set to 'False' where the other two were set to 'True'. I set the other two to false and they worked. So what is going on here? Why would this cause the error; is the GridView somehow doing a post back and loosing settings when this value is set?
I am writing a search results page for an airline booking system. I have Next/Previous buttons to view flights for the next or previous days. The way i have done my results grid is that i use an HtmlTable and dynamically add rows, cells and controls into the cells. This gives ultimate flexibility given that we can add any control type we want and have it function as it does everywhere else in the system. As you should be aware - i must recreate these controls each time the page is reloaded (in the page_init event) since asp does not handle this automatically.
When they go next/previous it refreshes the flight data and re-populates the grids. If they select a flight in the return grid (by checking the RadioButton), and go next on the FIRST leg grid, the selection of the return leg stays the same after the postback - which is great. But the problem is, if the flight they selected on the return leg is no longer available it will not create the control and i get the following error;
"Microsoft JScript runtime error: Sys.WebForms.PageRequestManagerServerErrorException: Failed to load viewstate. The control tree into which viewstate is being loaded must match the control tree that was used to save viewstate during the previous request. For example, when adding controls dynamically, the controls added during a post-back must match the type and position of the controls added during the initial request."
Is there any way to tell asp.net that if you do not find the control anymore, simply ignore it rather than throwing the error? The nature of this design is that there potentioally WILL be a different layout after the page is posted back.
I am retrieving results from a SQL database based on a user file upload, and I am saving the returned results in a datatable. It can be up to 15,000 rows. I need to use this datatable in other requests in this same page - i.e. saving the data back to another table, exporting to a file....How can I store the datatable to access again? I read up on viewstate, session , and cache, but they all seem to have an affect on performance and memory.
Basically I have images details which are stored in a database and would need to dynamically added hence, why i need to write within a div container. Any ideas how I could achieve this?
I have a situation where I want a user to select a file, then select an option from a DropDownList. When they select an item from the DropDownList I do an auto post back and do some stuff with the file, but this causes the path to clear out. Is there some way that I can keep the path from clearing out?
I have recently started learning ASP.NET with MVC 2 Framework, I am facing difficulties in the following scenarios.In my MVC application I want to retain partial information in Model over post backs.Following is my scenario,
1. I initiate "Edit" of main record by clicking date hyperlink from left navigation.
2. Amend some data.
3. Save the record.
4. "Edit" sub record of the saved record by clicking another hyperlink from bottom left navigation panel.
The page is divided in to 6 tabs, the first 5 tabs shows the data for the main record and the 6th tab shows data of sub record. Wehn we "Edit@ sub record the previous 5 tabs doesn't have any changes noted, that means there is no harm in keeping their details intact in the main model. So is there a way to access model in the controller on hyper link click action so that I can only load the data for the clicked sub record (I am asking this, because the hyperlink click uses HTTP GET method so no model parameter passed in action method). If no, then how do I retain partial values in the Model over post backs?
Note that each tab data have been kept in individual models, and a main model has a collection member to hold all these individual models together.I thought as the model is binded with the view, it is too binded with controller. But it is allowing easily to access model in variable "Model" for the view but not for the controller.
I have created a rdlc file (Binded its columns accordingly, sorting is enabled on few columns) and rendering it using a reportviewer control. Everything works fine while loading report first time; it shows the progress indicator & loads it correctly. When I click on sort_button(default shown by control itself) it sorts correctly. Now successive clicks on sort_button shows error :
An error occurred during local report processing. An internal error occurred on the report server. See the error log for more details. Gone through the log at server:
Program FilesMicrosoft SQL ServerMSSQL.3Reporting ServicesLogFilesReportServerService__01_19_2010_01_34_05.log but not able to deduce any fruitful exception.
Trace value in config file is set to :< add value="3" />
Either disable the sort_button till the report loads completely. Or show the progressbar indicator till the report loads completely.I am not able to find out the solution for: how to achieve any of the two ways mentioned above.
I am creating a survey page that has a list of questions and answers that can be radiobuttonlists, checkboxlists or textboxes. These controls are added dynamically to a Repeater in its ItemDataBound event using Controls.Add.
I've managed to render the page ok but when I submit the form and iterate over the controls in the repeater to get the selectedvalues of the radiobuttons and textbox values, FindControl returns null. What do I need to do to get get the selected values? I've tried iterating over the RepeaterItems but that returned null too. I've tried different types of FindControl but it never resolves the control types.
It works if I add a declarative DataBinder in the Repeater like this
However, I want want to dynamically add the controls but in doing this i cant get the selectedvalues when submitting. This is tha main structure of my code...
Ihave the following code and would like to be able to control the layout of the textboxes and labels so they arent just in a long column. Right now everything works and controls are added, but they are added in 1 column which if you chose 32 from the dropdown the page becomes very long.. so would like to maybe wrap them across 3 columns so that each has at least 10 per column.
I have a C# web application that dynamically adds user controls to the default page for whatever "mode" the application is in. The problem is that it is not persisting these across postbacks. How do I persist these across postbacks and keep the content of the controls that are in the user control?
For instance, say I have a user control that creates a new tour record. The user clicks on the Tour item from the menu on the default page, it dynamically loads the tours user control. The user then fills out the form in the tours user control and clicks save. This is where the problem happens. When the postback occurs, the web application has no idea that the new tours user control was ever loaded. So, no save takes place because the Save button's click event never even gets fired.
The following link describes the relationships between a Partial View and its parent in terms of ViewData: [URL] In relation to the text: "A partial view enables you to define a view that will be rendered inside a parent view. Partial views are implemented as ASP.NET user controls (.ascx).
When a partial view is instantiated, it gets its own copy of the ViewDataDictionary object that is available to the parent view. The partial view therefore has access to the data of the parent view. However, if the partial view updates the data, those updates affect only the partial view's ViewData object. The parent view's data is not changed"
how the parent view can make use of the new data added or existing data changed and updated, by the partial views? My question is around how to load partial views dynamically at runtime using Html.RenderPartial(...) whilst having one version of the data used and updated by the parent view and it's children.
I have ONE <asp:Button ID="btnAddUC" runat="server" ......./> and ONE <asp:Table ID="tblUC" runat="server"...> on my page. User clicks on btnAddUC, user control is added to the page [user can add 'n' user controls to the page]. here I have no problem, adding user controls to the page on user clicks.
My user control has ONE <asp:DropDownList ID="ddlItems" runat="server" ......./> and ONE <asp:CheckBoxList ID="chkItems" runat="server"..../>. I am exposing "ddlItems" by public method, "chkItems" is not exposed. "chkItems" is binded on SelectedIndexChanged event of "ddlItems".
Execution scenario:
User adds user control to the page, select item from the "ddlItems" ( Note: "ddlItems" is exposed by public property ) , "chkItems" is populated ( using ddlItems.SelectedItem.Value ) . User checks some checkboxes in "chkItems" and then decide to add one more user control. When the second user control is added to the page, checkboxes in the first usercontrol lose their state and apeears unchecked (NOTE: user checked some checkboxes and then added another user control).
I want to put checked beckboxes index in session ( Before another control is added, which event I should use, because at LOAD event there is nothing).
I was able to restict SelectedIndexChanged event to only that user control whcih generated it (checking _EVENTTARGET)
I'm dynamically adding a DropDownList to the GridView in edit mode and I have set the TextBox Visibility to False. In edit mode I can see the DropDownList and I'm able to select an Item from the DropDownList but not able to access the SelectedValue in RowUpdating Event. How to get the selectedvalue of this DropDownList?
Protected Sub GridView1_RowDataBound(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.GridViewRowEventArgs) Handles GridView1.RowDataBound If e.Row.RowType = DataControlRowType.DataRow And (e.Row.RowState And DataControlRowState.Edit) > 0 Then Dim ddl as DropDownList FillStateList(ddl) e.Row.Cells(4).Controls.Add(ddl)
ddl is the DropDownList that is added dynamically. And the default Textbox that is in the Edit mode is set to invisible. So there are actually two controls in the same cell in edit mode(TextBox is invisible).
If I use the above statement I'm getting NullException.This is Probably because its a BoundField. Is there a way I can access the DropDownList 'ddl' SelectedValue?
I am adding linkbutton dynamically (actually above snippet tells what I am actually doing, in reality TableRow and TableCell are added dynamiccally). My problem is, I am not setting height of linkbuttuon which will added dynamically. I have no idea what text I have to add to linkbutton.
What I want, after all the link buttons are added, iterate through each added lin button, get the height of each linkbutton, store the max height, then re-iterate throgh the link buttons and set the height of each link button to max height.
I am having datagridview control with dynamically added BoundField columns.I want to have tetxboxes in each cell of the gridview so taht user will enter data in gridview textboxes and at last on button click it will be saved in database.