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Enter Does Not Work For Submit, ASP.NET Page Refreshes and Doesn't Search

I am working with an ASP.NET site with a C# back end. There is a .Master page where the tag is, and other search pages on the site will search when you hit enter after filling out the form. However we have one page that has a few text boxes and when you hit enter to search, it appears to just refresh and reload the page without searching. In order to search you have to hit the search button (which is an igtxt:WebImageButton ). All of the solutions I have found to this issue so far involve people using javascript to call some kind of function on submit. As far as I know there is no javascript being called when you hit the search button, it is all in the C# code. Once again I find myself searching SO and other sites for an answer but none of the solutions seem to fit my situation. The form tag is as follows:
<form id="form1" runat="server">
The web image buttons call a btn_SearchClick function that runs the search code. But since the form is started in the .Master file I can't edit that as it would effect all other pages as well. Is there any way to have enter call the btn_SearchClick from the form without having to put it in the form tag? I'm not sure what would've changed to cause this behavior on one page and none of the others.

if (!IsPostBack)
{
TextBox1.Attributes.Add("onKeyPress",
"doClick('" + btnSearch.ClientID + "',event)");
}
<SCRIPT type=text/javascript>
function doClick(buttonName,e)
{
//the purpose of this function is to allow the enter key to
//point to the correct button to click.
var key;
if(window.event)
key = window.event.keyCode; //IE
else
key = e.which; //firefox
if (key == 13)
{
//Get the button the user wants to have clicked
var btn = document.getElementById(buttonName);
if (btn != null)
{ //If we find the button click it
btn.click();
event.keyCode = 0
}
}
}
</SCRIPT>
or u can use default button.it's work while cursor's in this box
protected void Page_Load(object sender, EventArgs e)
{
this.Form.DefaultButton = this.btnSubmit.UniqueID;
}

Add some jquery to control the Enter key behavior on your textbox. Something like this:
$(function() {
$('#<%=txtTextbox.ClientID%>').keypress(function (e) {
if (e.which == 13) {
e.preventDefault();
$('#<%=btn_SearchClick.ClientID%>').click();
}
});
});

How to add class for only the selected link in C# code behind?

I have a class called "is-active" and it has a colored arrow that sticks out from the nav into the main content based on which link the user clicked. The code runs a foreach and pulls all the categories from the database. How do I get the "is-active" class to display only for the current link? I know it works since I put it in the openList control and it displayed on all five categories, I just don't know how to get it to display on only the selected category.
I tried attaching jQuery to do it but adding the linkbutton is done all in the code behind so I am not sure how to attach the two. Is this the only way or is there another way?
Thank you in advance for your help!
Below is my code for the categories and link button:
protected override void CreateChildControls()
{
LiteralControl openingDiv = new LiteralControl("<div id='MainPanel'>");
LiteralControl closingDiv = new LiteralControl("</div>");
this.Controls.Add(openingDiv);
foreach (DataRow dr in ds.Tables[0].Rows)
{
LiteralControl openList = new LiteralControl("<li class='" + dr["CategoryColor"].ToString() + "'>");
LiteralControl closeList = new LiteralControl("</li>");
Label lblNumber = new Label();
LinkButton myLinkButton = new LinkButton();
myLinkButton.Text = "<span class='number'>" + dr["CategoryNumber"] + "</span>"+ dr["CategoryName"].ToString();
myLinkButton.CommandArgument = dr["Category_ID"].ToString();
myLinkButton.Click += myLinkButton_Click;
this.Controls.Add(openList);
this.Controls.Add(myLinkButton);
this.Controls.Add(closeList);
}
this.Controls.Add(closingDiv);
}
void myLinkButton_Click(object sender, EventArgs e)
{
LinkButton btn = (LinkButton)(sender);
Session["CategoryID"] = btn.CommandArgument;
Response.Redirect(Request.RawUrl);
}

Its tricky because your response.redirecting in the button click handler which recreates the pages viewstate.
This means that your page will always appear as fresh and the fact a user has clicked that link has been lost.
as a workaround you could place the link id in a session variable before you response.redirect and then recall it when the page reloads.
then when in your loop, if the session variable matches the current button instance.id you set cssclass equal to is-active.
remember to clear the session variable too after you set the cssclass to is-active to avoid confusion in other pages.
also, you will have to do the id comparison after you add the button to the control tree, because this is where the system automatically generates the id for you. I can give you a full example if you wish.
keep in mind that this is a workaround and a different approach would be best.
by this I mean that if you were to use an ispostback wrapper instead of a redirect, then on postback you could set the id to isactive much easier.
Page lifecycle is an important thing to get your head around in .net if you wish to be more proficient, especially as you mention that your using ajax update panels.
Read this: http://msdn.microsoft.com/en-us/library/ms178472(VS.100).aspx it's a lot of information to take in, so bookmark it for later too as you will use it a lot.

How to use an ajax modal popup and consume a value from a link?

I've read a few articles regarding getting values back from a modal popup in an ASP .NET page, but they all seem to use JavaScript to accomplish this which isn't really want I want to do if possible.
I have a web user control which has a repeater that I populate from a list into a table. Each row has a link button which has a redirect url with a value as a query string.
Then I have another web user control which is just a link button with a panel and the repeater web user control that once clicked shows the actual modal popup.
Is it possible to get a value from the web user control once the link button on the repeater is clicked without having to redirect to the same page? I basically want to click on the link, show the modal and once closed, want to access the value.
I'm populating the repeater with the links as follows:
string linkUrl = "";
string action = "";
if (Request.QueryString["action"] != null)
{
action = Request.QueryString["action"];
switch (action)
{
case "SetupCompany":
{
linkUrl = "<a href=CreateCompanies.aspx?companyId=";
break;
}
case "ViewCompany":
{
linkUrl = "<a href=ViewCompany.aspx?companyId=";
break;
}
}
}
CompaniesBusinessManager mgr = new CompaniesBusinessManager();
var companies = mgr.GetCompanies(txtCompanyName.Text, txtRegistrationNumber.Text);
if (linkUrl != "")
{
foreach (var c in companies)
{
c.Name = linkUrl + c.Id.ToString() + "&action=" + action + ">" + c.Name + "</a>";
}
}
rptrCompanies.DataSource = companies;
rptrCompanies.DataBind();

if you don't want the page to be redirected, you will need to use javascript.
There is now way you can pass values from different controls without going back to the server.
In case you keep it without the javascript:
I think you need to pass values from one user control to another. I used to accomplish this by firing reachable events between them.
For example:
in your parent view:
<uc:YourUserControl runat="server" ID="UserControl_Test"
OnYourCustomAction="UserControl_YourUserControl_YourCustomAction" />
In your user control:
public event EventHandler<CustomActionEventArgs> YourCustomAction;
also in the same user control create a public trigger method to be access from others usercontrols
public void TriggerCustomActoinEvent(CustomActionEventArgs EventArgs)
{
if (this.YourCustomAction!= null)
{
this.YourCustomAction(this, EventArgs);
}
}
Hope this help, in on my way to home this was from my mind!

Without a page postback or JavaScript it not really possible. If you are using modal popups you are already using JS, so why not just get the value in JS? You could setup an event handler for all repeater buttons and if they are loaded via ajax use something like this to attach the event handler:
$(document).on('click', '.repeaterButton', function(e) {
var valueOfBtnClicked = $(this).val();
// Do something else
});

How to check whether postback caused by a Dynamic link button

I have a button control. On click of this button I need to add a Link Button dynamically. The Link Button needs an event handler. Hence the dynamic Link button is first added in the Page_Load and cleared and added again in the button click handler. Please read Dynamic Control’s Event Handler’s Working for understanding the business requirement for this.
I have read On postback, how can I check which control cause postback in Page_Init event for identifying the control that caused the postback (inside Page_Load). But it is not working for my scenario.
What change need to be done to confirm whether the postback was caused by link button (inside Page_Load)?
Note: Refer the following for another scenario where it is inevitable https://codereview.stackexchange.com/questions/20510/custom-paging-in-asp-net-web-application
Note 1: I need to get the postback control ID as the first step inside if (Page.IsPostBack). I need to add the dynamic link buttons control only if it is a postback from the button or the link button. There will be other controls that causes postback. For such postbacks we should not execute this code.
Note 2: I am getting empty string for Request["__EVENTARGUMENT"] in the Page_Load
Related Question: By what event, the dynamic controls will be available in the Page (for using in FindControl). #Tung says - "Your GetPostBackControlId method is properly getting the name of the control that caused the postback, but it is unable to find a control with that id through page.FindControl because the linkbutton has not been created yet, and so page does not know of its existence. "
ASPX
<%# Page Language="C#" AutoEventWireup="true" CodeFile="PostbackTest.aspx.cs" Inherits="PostbackTest"
MasterPageFile="~/TestMasterPage.master" %>
<asp:Content ID="myContent" ContentPlaceHolderID="ContentPlaceHolder1" runat="server">
<div id="holder" runat="server">
</div>
<asp:Button ID="Button1" runat="server" Text="Button" OnClick="TestClick" />
</asp:Content>
CODE BEHIND
public partial class PostbackTest : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
if(Page.IsPostBack)
{
string IDValue = GetPostBackControlId(this.Page);
int x = 0;
holder.Controls.Clear();
LinkButton lnkDynamic = new LinkButton();
lnkDynamic.Click += new EventHandler(LinkClick);
lnkDynamic.ID = "lnkDynamic123";
lnkDynamic.Text = "lnkDynamic123";
holder.Controls.Add(lnkDynamic);
}
}
protected void TestClick(object sender, EventArgs e)
{
holder.Controls.Clear();
LinkButton lnkDynamic = new LinkButton();
lnkDynamic.Click += new EventHandler(LinkClick);
lnkDynamic.ID = "lnkDynamic123";
lnkDynamic.Text = "lnkDynamic123";
holder.Controls.Add(lnkDynamic);
}
protected void LinkClick(object sender, EventArgs e)
{
}
public static string GetPostBackControlId(Page page)
{
if (!page.IsPostBack)
{
return string.Empty;
}
Control control = null;
// First check the "__EVENTTARGET" for controls with "_doPostBack" function
string controlName = page.Request.Params["__EVENTTARGET"];
if (!String.IsNullOrEmpty(controlName))
{
control = page.FindControl(controlName);
}
else
{
// if __EVENTTARGET is null, the control is a button type
string controlId;
Control foundControl;
foreach (string ctl in page.Request.Form)
{
// Handle ImageButton they having an additional "quasi-property" in their Id which identifies mouse x and y coordinates
if (ctl.EndsWith(".x") || ctl.EndsWith(".y"))
{
controlId = ctl.Substring(0, ctl.Length - 2);
foundControl = page.FindControl(controlId);
}
else
{
foundControl = page.FindControl(ctl);
}
if (!(foundControl is Button || foundControl is ImageButton)) continue;
control = foundControl;
break;
}
}
return control == null ? String.Empty : control.ID;
}
}
REFERENCE
On postback, how can I check which control cause postback in Page_Init event
Dynamic Control’s Event Handler’s Working
Understanding the JavaScript __doPostBack Function
Access JavaScript variables on PostBack using ASP.NET Code
How does ASP.NET know which event to fire during a postback?
how to remove 'name' attribute from server controls?
How to use __doPostBack()

A postback in asp.net is done by the java script function __doPostback(source, parameter)
so in your case it would be
__doPostback("lnkDynamic123","") something like this
So in the code behind do the following
var btnTrigger = Request["__EVENTTARGET"];
if(btnTrigger=="lnkDynamic123")
{
}
--- this would tell that it is your linkbutton that causes the postback

You can move the call to the GetPostBackControlId method after the LinkButton has been added to the page:
protected void Page_Load(object sender, EventArgs e)
{
if (Page.IsPostBack)
{
holder.Controls.Clear();
LinkButton lnkDynamic = new LinkButton();
lnkDynamic.Click += new EventHandler(LinkClick);
lnkDynamic.ID = "lnkDynamic123";
lnkDynamic.Text = "lnkDynamic123";
holder.Controls.Add(lnkDynamic);
string IDValue = GetPostBackControlId(this.Page);
if (IDValue == lnkDynamic.ID)
LinkClick(lnkDynamic, new EventArgs());
}
}
Calling the click event handler here also more closely mimics the standard ASP.NET Page Life Cycle, where Postback event handling occurs after the Load event.
Edit:
If the control ID must be determined before the LinkButtons are created, you can create a naming scheme for the link button IDs, e.g. lnkDynamic_1, lnkDynamic_2 etc.
Request["__EVENTTARGET"] will then contain the auto-generated control ID such as “ctl00$mc$lnkDynamic_1”, which you can use to identify which LinkButton caused the postback.

If You're getting the post back control id correctly but FindControl returns nothing, then it's probably because You're using a master page. Basically, someControl.FindControl(id) searches through controls that are in someControl.NamingContainer naming container. But in Your case, the Button1 control is in the ContentPlaceHolder1, which is a naming container, and not directly in the Page naming container, so You won't find it by invoking Page.FindControl. If You can't predict in which naming container the control You're looking for is going to be (e.g. post back can be caused by two different buttons from two different content placeholders), then You can write an extension that'll search for a control recursively, like so:
public static class Extensions
{
public static Control FindControlRecursively(this Control control, string id)
{
if (control.ID == id)
return control;
Control result = default(Control);
foreach (Control child in control.Controls)
{
result = child.FindControlRecursively(id);
if (result != default(Control)) break;
}
return result;
}
}
Use it with caution though, because this method will return the first control that it finds with the specified id (and You can have multiple controls with the same id - but they should be in different naming containers; naming containers are meant to differentiate between controls with same ids, just as namespaces are meant to differentiate between classes with same names).
Alternatively, You could try to use FindControl(string id, int pathOffset) overload, but I think it's pretty tricky.
Also, check this question out.

First approach (wouldn't recommend but it's more flexible)
One completely different approach - although I don't really feel like I should promote it - is to add a hidden field to the form.
The value of this hidden field might be something like false by default.
In case of clicking one of the dynamic buttons which should cause the dynamic controls to be added again, you can simply change the hidden fields value to true on client side before performing the postback (eventually you want/have to modify the client side onclick handler to make this happen).
Of course it would be possible to store more information in such a field, like the controls id and the argument (but you can get those values as described in the other answers). No naming schema would be required in this case.
This hidden field could be "static". So it would be accessible in code behind all time. Anyhow, you might want to implement something to make sure that nobody is playing around with its values and fakes a callback which looks like it originated from one of these dynamic links.
However, this whole approach just helps you getting the id of the control. Until you create the control again, you won't be able to get the instance through NamingContainer.FindControl (as mentioned in the other answers already ;)). And in case you create it, you don't need to find it anymore.
Second approach (might not be suitable due to its contraints)
If you want to do it the clean way, you need to create your controls OnLoad, no matter if something was clicked or not. Additionally, the dynamic controls ID has to be the same as the one you sent to the client in the first place. You subscribe to its Click or Command event and set its visibility to false. Inside the click event handler, you set the senders visibility to true again. This implies, that you don't care if that link is created but instead just don't want to send it to the client. The example below only works for a single link of course (but you could easily modify it to cover a whole group of links).
public void Page_Load(object sender, EventArgs e)
{
LinkButton dynamicButton = new LinkButton();
dynamicButton.ID = "linkDynamic123";
// this id needs to be the same as it was when you
// first sent the page containing the dynamic link to the client
dynamicButton.Click += DynamicButton_Click;
dynamicButton.Visible = false;
Controls.Add(dynamicButton);
}
public void DynamicButton_Click(object sender, EventArgs e)
{
// as you created the control during Page.Load, this event will be fired.
((LinkButton)sender).Visible = true;
}

Dynamic Controls - C# - CheckBoxList Parent - Children

First I understand the need to build dynamic controls in the OnInit Section.
However, I read a document from Scott Guthrie?
http://scottonwriting.net/sowblog/archive/2004/10/08/162998.aspx
So I got the impression from these blogs that if you add the control to the container then modify the properties, you can get at the control in the Page_Load.
In a nutshell, I have a table with a fk back to the table creating a hierarchy.
I load 3 usercontrols the page with checkbox lists that relate back through the parent key.
Table like this:
create table myTbl
(
id int identity,
par_id int,
item_desc varchar(25)
other_desc_flag bit
)
What my clients need is the ability to make a checkbox selection.
The child set of textboxes will display based on the parent.
If the txt_flag is set, a checkbox entry will not be populated.
Instead, they want the desc label printed out with a textbox for response.
The user data is not kept in the table above by the way.
So the issue I have is these text responses can be at any level of the custom control.
So I created a class with a 3 items ( id, literal control, and a textbox ).
I then dynamically create the controls based on the selection at any particular level.
I read each level into a dataset, I iterate through the dataset looking for that flag.
I capture an index variable in the rows with this flag and I create a List class to hold the
id, text_desc. I then remove the row from the table in the dataset and bind the remaining items to the checkboxlist.
I then go back to my control and write out dynamically the controls.
But like all those before me, I am doing evil battle against the Page Cycle...lol.
I cannot see the controls. I plan to DataBind() my controls separately on load as I have not gotten to the point where I'm getting the clients reponses from the database. That's for another day. The placeholder with my dynamic controls is OtherPlaceHolder. I have tried setting the Viewstate to true and false.
Any pointers on how to get the # of items on postback into a session variable so I can create the controls on the OnInit section.
Here is the code. This is being run from a Master Page...
On the controls, I changed the < & > to [ ] because this page that attempts to put code into
a controlbox with scrollbars was cutting off that code.
[asp:UpdatePanel ID="UpdPanel" runat="server" EnableViewState="true" UpdateMode="Always"]
[ContentTemplate]
[asp:Table runat="server" ID="ContainerTbl"]
[asp:TableHeaderRow]
[asp:TableHeaderCell ColumnSpan="2" CssClass="tdCell"][asp:Literal ID="LitDesc" runat="server" Text="Level" /][/asp:TableHeaderCell]
[/asp:TableHeaderRow]
[asp:TableRow]
[asp:TableCell runat="server" ID="tblItems" VerticalAlign="top"]
[asp:PlaceHolder runat="server" ID="CtrlPlaceHolder"]
[asp:CheckBoxList ID="cboItems" Visible="false" runat="server" AutoPostBack="true"][/asp:CheckBoxList]
[asp:HiddenField ID="otherCnt" runat="server" /]
[/asp:PlaceHolder]
[asp:PlaceHolder runat="server" ID="OtherPlaceHolder" EnableViewState="false"]
[/asp:PlaceHolder]
[/asp:TableCell]
[/asp:TableRow]
[asp:TableRow]
[asp:TableCell VerticalAlign="top"]
[asp:Label ID="LabMsg" runat="server" CSSClass="tdCell" Font-Bold="true" Visible="false"/]
[/asp:TableCell]
[/asp:TableRow]
[/asp:Table]
[asp:HiddenField ID="hLevel" runat="server" Value="" /]
[/ContentTemplate]
[/asp:UpdatePanel]
private void WriteOutQuestions(List<Questions> qList)
{
int itemCnt = 1;
// clear any controls in other place holder first.
OtherPlaceHolder.Controls.Clear();
Table OTD = new Table();
foreach (Questions qst in qList)
{
// we're going to create the new control and add to
// the placeholder - OtherPlaceholder
// we'll then reference those controls and add the data to those
// controls.
// see dynamic control article: http://scottonwriting.net/sowblog/archive/2004/10/08/162998.aspx
HiddenField hItemId = new HiddenField();
TextBox txtItem = new TextBox();
LiteralControl ltcItem = new LiteralControl();
// add the new controls
string strItemId = "hItem" + Convert.ToString(itemCnt);
string strTxtItem = "txtItem" + Convert.ToString(itemCnt);
string strLtcItem = "ltcItem" + Convert.ToString(itemCnt);
hItemId.ID = strItemId;
hItemId.EnableViewState = true;
txtItem.ID = strTxtItem;
txtItem.EnableViewState = true;
ltcItem.ID = strLtcItem;
ltcItem.EnableViewState = true;
OTD.Controls.Add(OtherDescAddControl(OtherPlaceHolder, hItemId, ltcItem, txtItem));
// now reference the new added controls and set values from Question object...
++itemCnt;
}
OtherPlaceHolder.Controls.Add(OTD);
// now post data to controls...
itemCnt = 1;
foreach (Questions qst in qList)
{
string strItemId = "hItem" + Convert.ToString(itemCnt);
string strTxtItem = "txtItem" + Convert.ToString(itemCnt);
string strLtcItem = "ltcItem" + Convert.ToString(itemCnt);
HiddenField hfld = (HiddenField)OtherPlaceHolder.FindControl(strItemId);
TextBox txtBox = (TextBox)OtherPlaceHolder.FindControl(strTxtItem);
LiteralControl ltx = (LiteralControl)OtherPlaceHolder.FindControl(strLtcItem);
hfld.Value = qst.HFld.ToString();
txtBox.Text = qst.TxtBox;
txtBox.Attributes.Add("class", "txtBox");
ltx.Text = qst.Ltc.ToString();
++itemCnt;
}
//decrement itemCnt and populate box here...
--itemCnt;
HiddenField hfldCnt = (HiddenField)CtrlPlaceHolder.FindControl("otherCnt");
hfldCnt.Value = Convert.ToString(itemCnt);
hfldCnt.Visible = true;
}

On the assumption that when you say "I cannot see the controls" you mean that you're getting null references when you try to access them in the postback (rather than that the HTML doesn't contain them), have you tried using Page.EnsureChildControls()?

Ok If I understood your question right, you want to save your controls and load them back on postbacks. Here is what you can do:
List<HiddenField> HiddenFields = new List<HiddenField>{};
List<TextBox> TextBoxs = new List<TextBox>{};
List<LiteralControl> LiteralControls = new List<LiteralControl>{};
OTD.Controls.Add(OtherDescAddControl(OtherPlaceHolder, hItemId, ltcItem, txtItem));
// do this for all your items that you load to page (add them to your list).
HiddenFields.Add(hItemId);
// when you are done with loading all your controls to page, add your populated Lists to session.
Session["HiddenFields"] = HiddenFields;
//On Page_Init or Page_Load, simpy load them back IF **page is postback**.
If(Page.IsPostBack)
{
LoadControlsFromSession();
}
private void LoadControlsFromSession()
{
HiddenFields = Session["HiddenFields"] as List<HiddenFields>;
// Load all your List objects from session like above.
int counter = 0;
if(HiddenFields != null)
{
foreach(HiddenField hdnField in HiddenFields)
{
//load your objects with the same method you have from your List.
OTD.Controls.Add(OtherDescAddControl(OtherPlaceHolder, HiddenFields[counter], LiteralControls[counter], TextBoxs[counter]));
counter++;
}
}
}

I apologize for lack of clarity.
I believe I did try setting Session variables in my classes when I created the controls and they were null on postback. I tried to access the session variable in the page init and preload and zip.
I did find an interesting workaround to this problem. On page_unload I parsed through the controls into an arraylist of hashtables of the database id & user'sentered text answer.