Hai guys,
I used find control to find a list item of an unoreder list inside a master page from content page using this,
Control home = this.Page.Master.FindControl("list").FindControl("home");
Now i have to change the id of the control home to "current" because to apply css for it....
Do you know the Type of the control you're finding? Neither Control nor ListItem expose a CssClass property, however, ListItem does expose it's Attributes property.
Update based on comment and other question:
You should be using System.Web.UI.HtmlControls.HtmlGenericControl
So something like this should work for you:
HtmlGenericControl home =
this.Page.Master.FindControl("list").FindControl("home")
as HtmlGenericControl;
string cssToApply = "active_navigation";
if (null != home) {
home.Attributes.Add("class", cssToApply);
}
If you think there might already be an class assigned to it that you need to append to you could do something like:
if (null != home) {
if (home.Attributes.ContainsKey("class")) {
if (!home.Attributes["class"].Contains(cssToApply)){
// If there's already a class attribute, and it doesn't already
// contain the class we want to add:
home.Attributes["class"] += " " + cssToApply;
}
}
else {
// Just add the new class
home.Attributes.Add("class", cssToApply);
}
}
If they aren't ListItems, cast them to the correct type, and modify the attributes collection as before, unless there's a CssClass property for that type.
Yes, to use css id's in asp.net is a big problem. first of all you can change your server control's id to what you want but, this will be regenerated by ASP.NET depending on the position of the control in your page's control tree.
My recommendation is to use cssclass property of the controls, and to replace the css ids to class.
Related
I have an asp:ListView whose ClientIDMode is set to Predictable. Its ItemTemplate contains an asp:textbox.
The ID of the textbox is acting as I expect it to, but its name is still using what looks like an AutoID-style algorithm:
<input name="lvFields$ctrl0$tbVal" id="lvFields_tbVal_somekey" type="text"/>
Is there a way for me to cause the name of the input to act like the ID does?
(Edit in response to questions below:)
The Name of the input element is what's in the POST data, so if a postback alters the list to which the ListView is bound (for example, exchanging two elements) the values from the textboxes end up associated with the wrong keys, because the framework is correlating them based on the Name and not the ID.
You can change the name of an Input by using the method from the following post but modifying it slightly:
how to remove 'name' attribute from server controls?
I over-rode the RenderChildren method on a Page control as I just wanted full control of the HTML for a few controls:
protected override void RenderChildren(HtmlTextWriter writer)
{
var unScrewNamesRender = new RenderBasicNameHtmlTextWriter(writer);
base.RenderChildren(unScrewNamesRender);
}
private class RenderBasicNameHtmlTextWriter : HtmlTextWriter
{
public RenderBasicNameHtmlTextWriter(TextWriter writer) : base(writer) { }
public override void AddAttribute(HtmlTextWriterAttribute key, string value)
{
if (key == HtmlTextWriterAttribute.Name && value.Contains("POLine"))
{
value = value.Substring(value.LastIndexOf("$") + 1);
}
base.AddAttribute(key, value);
}
}
You do need to know what you're doing if you attempt this, WebForms will think the control is missing so you can't use it in any postbacks. For my purposes, where I wanted to add an arbitrary number of multiple lines either server or client-side without having to deal with .Net Ajax controls, it works fine.
I'm pretty sure you can't change the name, especially when you modify the ClientIDMode. As an alternative, you can add a Title attribute. VS will flag this as unknown in the server side code, but it renders correctly in the HTML. If you're doing some client-side manipulation, you can address the input as such:
<script type="text/javascript">
$(document).ready(function () {
$('input:text[title="TextBoxName"]').datepicker();
});
</script>
As far as I know, there is no way to change the name of the input element. The name corresponds to the UniqueID property, which is generated by the system, and which you have no control over. Seems you have to find a way to achieve what yo want using only the control ID.
Both names are using the predictable pattern; originally, name also equaled ct100_ct100 etc. From what I see, that's a predictable name. Client ID value will always use _ between control prefixes and Unique ID (name attrib) will always use $. The two will always match, except for a few controls that leverage name for something (radiobuttonlist uses for grouping).
HTH.
I had the exact same problem once and had to use one of these properties exposed in "System.Web.UI.Control" to get clientside control name in server side.
Play around with these properties and construct the "Name" in server side yourself and use Request.Form("NameHere")
Me.ClientIDSeparator
Me.IdSeparator
Me.UniqueID
A jquery solution
function removeNameAttribute() {
$('input, select').each(function () {
$(this).removeAttr("name");
});
}
//Use a HtmlGenericControl
HtmlGenericControl input = new HtmlGenericControl("input");``
input.ID = "lvFields_tbVal_somekey";
input.Attributes.Add("name", "tbVal");
input.Attributes.Add("type", "text");
input.ClientIDMode = ClientIDMode.Static;
What is the trick to get the controls inside the FormView. I was getting them with FindControl() but, now i cant get access on them. Example: i have some ImageButton on the FooterTemplate, great i can get those smoothly, when it comes to the controls inside the FormView!!! null every control. Do you think i should name them differently in every template?
This gets me thinking about the table causing this noise!
I'm using the DataBound Event and checking for specific Mode! Any ideas? Thank you.
[UPDATED]
This is working
if (this.kataSistimataFormView.CurrentMode == FormViewMode.Edit)
{
ImageButton update = (ImageButton)this.kataSistimataFormView.FindControl("btnUpdate");
update.Visible = true;
But this for some reason no
CheckBox chkBoxPaidoi = kataSistimataFormView.FindControl("chkBoxPaidoi") as CheckBox;
FindControl is not recursive. What I mean is that it will only find controls that are within the child controls of the control you are searching - it will not search any child controls of the child controls
If you have placed the control you previously were looking for within another control then you will have to either search within that new control or, if you still want to use kataSistimataFormView as the parent control, you may have to use a recursive search.
Google for "findcontrol recursive" there are some good examples that you can probably just cut-and-paste.
As it seems this was caused because of the same naming ID's on various templates, Insert,Edit,Item. Even this is supported by the compiler, has problem when you are going for them programmaticaly later.
Thank you all.
Did you ever get this figured out? If you know the ID you can use this recursive function:
private Control FindControlRecursive(Control root, string id)
{
if (root.ID == id)
{
return root;
}
foreach (Control c in root.Controls)
{
Control t = FindControlRecursive(c, id);
if (t != null)
{
return t;
}
}
return null;
}
Found here:
http://www.codinghorror.com/blog/2005/06/recursive-pagefindcontrol.html
I have sort of a table with a radio-button column. I managed to make radio-button column work dynamically inserting into a cell (div if matter). But, on postback innerHtml hasn't been updated with "checked" attribute.
Could you give me an idea how can I find out (on the server) if radio-button has been checked?
More info: This is on user control inside update panel.
This would be good post on my topic, still doesn't help
Any reason you cannot use a standard asp:RadioButton and use javascript to ensure it is mutually exclusive. I have done this before by adding a custom attribute to the radiobutton and then using a js function to uncheck all items with that attribute and then check the selected one. This works around the IE issue which prevents the groupname attribute from working on radioboxes that are in different containers.
radioButton.InputAttributes.Add("ClientGroupName", "grpRadioList");
radioButton.InputAttributes.Add("onclick",
string.Format(
"javascript:radiobuttonToggle('{0}','ClientGroupName','grpRadioList');"
,radioButton.ClientID));
and use the following JS to uncheck all radios and then check the one you want.
Note i used InputAttributes instead of Attributes as the radiobutton is wrapped inside a span tag so InputAttributes is for items added to the actual input control rather than the span.
function radiobuttonToggle(selectedRB, attribName, attribValue)
{
var objRadio = document.getElementById(selectedRB);
for(i = 0; i < document.forms[0].elements.length; i++)
{
elm = document.forms[0].elements[i];
if (elm.type == 'radio')
{
if(elm.getAttribute(attribName) == attribValue)
elm.checked = false;
}
}
objRadio.checked = true;
}
You can then expose radioButton.Checked as a property in your CS file and reuse this as a control.
Check Form.Request("radio-name") != null
You only get a non-null value when it's been checked.
Make sure your page elements are being rebuilt correctly on postback. Any binding process that inserted the radio buttons the first time around will have to be re-run before you can access them the second time.
Here is a working example, first I add radios to my webform by the method you linked :
function addRadio()
{
try{
rdo = document.createElement('<input type="radio" name="fldID" />');
}catch(err){
rdo = document.createElement('input');
}
rdo.setAttribute('type','radio');
rdo.setAttribute('name','fldID');
document.getElementById('container').appendChild(rdo);
}
Then at code behind I used only the code below to get the radio's value :
string value = Request["fldID"];
So, be sure you're trying to get the name of the radio buttons at server side. You should use name attribute at server side, not id.
I am trying to add a checkbox in a listview with value as ids of the records from the database so I can allow the user to check the ones they want to delete and when they click the delete button I can get value collection of checkbox with request.form.
My problem is, because checkbox in a listview ASP.NET renders the listview name into the name property of the checkbox, it prevents me to do request.form["checkboxname"].
I don't want to use Listviews delete commands but simply use request.form to get the collection of checked values.
How can I set name of the htmlinput checkbox so .NET doesn't change it in render time?
I have tried:
ListViewDataItem dataItem = (ListViewDataItem)e.Item;
HtmlInputCheckBox _CheckBoxDelete = (HtmlInputCheckBox)e.Item.FindControl("CheckBoxDelete");
_CheckBoxDelete.Visible = true;
_CheckBoxDelete.Value = DataBinder.Eval(dataItem.DataItem, "id").ToString();
_CheckBoxDelete.Name = "deletechecked";
But still it renders like:
<input name="PmList$ctrl0$CheckBoxDelete" type="checkbox" id="PmList_ctrl0_CheckBoxDelete" value="3" />
This is happening because ListView is a Naming Container. You can get around this in a couple of ways, but they all boil down to the choice of:
Rendering the HTML you want.
Pulling out the checked items in a different way.
The former is doable, but you'll likely loose a lot of ASP.NET's built in functionality. I'd advise against it unless you're deeply familiar with the control life cycle.
You've got everything you need for the pulling the values out in a way ASP is expecting:
HtmlInputCheckBox _CheckBoxDelete = (HtmlInputCheckBox)item.FindControl("CheckBoxDelete");
You just need to wait for the control hierarchy to be populated, and then loop over the ListView.Items looking for the checkboxes. Your "Delete" button's event handler is probably a good place to call this from.
Incidentally, why are you using a HtmlInputCheckbox, rather than a CheckBox?
I have sorted it out with:
string idCollectionTodelete = string.Empty;
foreach (string x in Request.Form)
{
if (x.IndexOf("CheckBoxDelete") > -1)
{
idCollectionTodelete += Request.Form[x] + ",";
}
}
new DB().DeleteUserPm(
ActiveUsername(), subdomain, idCollectionTodelete.TrimEnd(','));
It is not an ideal solution but it does work for me.
I do this
List<HtmlInputCheckBox> chkDeleteContacts = new List<HtmlInputCheckBox>();
foreach (RepeaterItem item in rptrFamilyContacts.Items)
{
chkDeleteContacts.Add((HtmlInputCheckBox)item.FindControl("chkDeleteContact"));
}
foreach(HtmlInputCheckBox chkDeleteContact in chkDeleteContacts)
{
//Delete Contact
if(chkDeleteContact.Checked)
blnStatus = BusinessUtility.DeleteConsumerContact(LoginConsumerID, chkDeleteContact.Value);
}
Slightly easier in my opinion
On Page_Load() in the codebehind, I'd like to enumerate all the <link> tags. The purpose being I want want to add a <link> to a CSS file if it isn't specified in the Page's markup.
How can I do this?
I'm thinking I should be able to use LINQ on the collection of elements in the header, no?
Here's my pseudocode:
var pageAlreadyContainsCssLink = false;
foreach(var control in this.Header.Controls) {
if (control.TagName == "link" &&
control.Attributes["href"] == "my_css_file.css") {
pageAlreadyContainsCssLink = true;
break;
}
}
if (pageAlreadyContainsCssLink) {
// Don't add <link> element
return;
}
// Add the <link> to the CSS
this.AddCssLink(...);
The solution is to enumerate the Controls collection as HtmlGeneric controls:
foreach(HtmlControl control in this.Header.Controls)
{
if (control is HtmlLink && control.Attributes["href"] == this.CssFileLinkHref)
{
pageAlreadyContainsCssLink = true;
break;
}
}
Yes, your code should work. However, this situation should be managed at the root, by preventing it from happening so you will not need to code something 'just in case' to deal with it.
Your loop checked for the occurance of the css link, and if it exists then exit. What if there are 2 or more occurance? Do you want to remove the duplicate(s)?
I would suggest using one or combination of the followings:
Masterpage (Single place for you to manage css files)
Theme (All css files are linked automatically ONCE per page request)
Code standandisation
Single custom control within the header for all pages (need to make sure item 3 is in place)
1 and 2 is not applicable to ASP.NET 1.x, 3 and 4 applies to all.