how can i set style attribute in code behind c#?
thanks
niall
Basically like this
Control.Style.Add("background-color", "red");
Or like this for any other attribute:
Control.Attributes.Add("style", "color: red;");
A user control isn't directly converted to a single HTML object - it is a collection of objects grouped together, therefore you can't set its "style".
If you want to hide it, then it should have a Visible attribute which you can set to false, however, this means that it won't be rendered to the page at all, and so subsequently can't be made visible in client code.
Related
I use goog.html.sanitizer.HtmlSanitizer.Builder to create safe HTML that I then dynamically insert into a dialog. I wanted to have an input field that uses the Html 5 "placeholder" attribute.
I tried
.alsoAllowTagsPrivateDoNotAccessOrElse ([ "placeholder"])
and got an expected nasty compiler error!
I ended up adding the place holder attribute to the closure-library attribute white list javascript code. The call to alsoAllowTagsPrivateDoNotAccessOrElse was removed and all worked well.
I am using/abusing CSS classes and custom html attributes to provide default data to a set of textboxes. The code-front for this looks like the following (with some supporting javascript to handle checking/setting the default data when the field is blank):
<asp:TextBox ID="TXT_LenderName" class='defaultText' data-default='Institution Name' runat="server"></asp:TextBox>
This works.
I am working on the code-behind to process this form. I would like to be able to compare the value of the TXT_LenderName.Text to the value of the data-default attribute, but I haven't been able to find a way to get the value of a custom html attribute. Suggestions?
This is tested and worked
string customAttrDataDefault = TXT_LenderName.Attributes["data-default"];
txtpassword.Attributes.Add("value","Password value");
try this:
TXT_LenderName.Attributes["AttributeName"]= value;//here get or set the value.
If the control, like the TextBox control inherits from the System.Web.UI.WebControls.Control class then it should have an Attributes property which is a name value pair collection of the control's attributes.
In my case, I have an HTML/CSS Menu in the site master.
So, when you hover your mouse over "Graphics", it highlights it (using CSS onHover).
Now what I need to do is that when you actually click on "Graphics" (and it takes you to the graphics page), it remains highlighted, if possible in a different colour.
I'm thinking of modifying the Site.Master style from C# or VB code.
Any ideas? Thanks.
An idea would be to check what page you are in, and apply a css class:
<li class="<%= this.Page.ToString().ToLower().EndsWith("graphics_aspx") ? "selected" : "normal"%>">
Graphics<li>
Hope it helps!
You can either use the CSS active state if the page you are on directly relates to the link, however if the menu points to sections (i.e. multiple pages) you may need to use a bit of server side code to your master page, that gets the requested URL and determines which link is active. Usual convention is to then add the class 'active' or similar to the outputted html.
You can convert the UL/LI with runat = "server" and finally add styles in the code behind
Example
Control.Style.Add("display", "none");
Is there an accepted way to "move" a control.
My client wants to place a certain chunk of markup (representing some visual element) in one of several different places on the page. The locations are different to the point that I can't effect the change on CSS along (by floating it or something).
I considered just putting the control in multiple spots with Visible set to "false," then displaying the one in the place they wanted for that particular page.
However, the code for this control is not trivial -- there's a couple template sections, for instance. Having to dupe this in multiple places would get unwieldy. Also, I don't want to have to work with this control strictly from the code-behind for the same reason.
So, I'd like to put it in one place on the Web form, the move it around based on where I want it. Could I put Placeholders in different spots, have the control in one spot, then remove and add it to the right spot? I suspect this would work.
Does someone have a better idea? Is there a best practice for this?
I'd recommend using a placeholder control, moving your markup into a separate user control, then loading this at runtime and adding it to the relevant placeholder.
Eg.
// Load a user control
MyControl userCtrl = (MyControl) LoadControl("~/Controls/MyControl.ascx");
// Or create an instance of your control
SubclassedControl subclassedCtrl = new SubclassedControl();
// Do stuff with controls here
userCtrl.LoadData();
subclassedCtrl.Text = "Hello World";
// Check which placeholder to add controls to
PlaceHolder placeHolder = (foo=="bar") ? placeHolder1 : placeHolder2;
// Add the controls
placeHolder.Controls.Add(userCtrl);
placeHolder.Controls.Add(subclassedCtrl);
This will avoid cluttering up your page with unnecessary markup, and loading it at runtime will also avoid unnecessary confusion later, when another developer looks at the code and can't immediately see why a control is in one place in the markup, but renders on a completely different part of the page.
An alternative (and one I've seen done many times before) is through javascript and the DOM. Render your control inside a hidden div tag. So you would render your content here:
<div id='rendercontent' style='display:none'>
.. control here ..
</div>
Then, lets say you wanted to move it all here (the span tag is inside because that's what we're going to replace):
<div id='newlocation1'><span></span></div>
You would define the following javascript:
<script language="JavaScript">
function replaceNode(newElementID, targetElementID)
{
var targetElement=document.getElementById(targetElementID);
var newElement=document.getElementById(newElementID);
targetElement.replaceChild(newElement, targetElement.firstChild);
}
</script>
And when you want to move the content to the new location, call:
<script language="JavaScript">
replaceNode('rendercontent','newlocation1');
</script>
Do Web Parts do what you want to do?
Or, you can change the parent programmatically of your controls to move them into a separate area.
You can override the Render method and place the controls wherever you want in the html.
You only need to add controls to the Controls collection that must interact on the server. The rest of your HTML can just be written to the response stream. If you override Render you can create the html anyway you see fit, placing the controls in any order.
Below is an example of how to write out your html.
protected override void Render(HtmlTextWriter writer)
{
AddAttributesToRender(writer);
writer.RenderBeginTag(TagKey);
writer.RenderBeginTag(HtmlTextWriterTag.Div);
_control.RenderControl(writer);
writer.RenderEndTag();
writer.RenderEndTag();
}
You could always put panels in the pre-defined locations and add the control to the specific panel at runtime.. Here's an example adding a label (the label could be replaced with any control).
Dim lblDisplay As Label = New Label()
lblDisplay.ID = "myLabel"
lblDisplay.Text = "Some Text"
pnlDisplay.Controls.Add(lblDisplay)
As far as...
"Also, I don't want to have to work
with this control strictly from the
code-behind for the same reason."
I think you're going to have to do most of your work in the code behind.
PS.. a good example of the whole usercontrol setup can be downloaded here..
http://www.asp.net/downloads/starter-kits/time-tracker/
Is it possible to prevent an asp.net Hyperlink control from linking, i.e. so that it appears as a label, without actually having to replace the control with a label? Maybe using CSS or setting an attribute?
I know that marking it as disabled works but then it gets displayed differently (greyed out).
To clarify my point, I have a list of user names at the top of my page which are built dynamically using a user control. Most of the time these names are linkable to an email page. However if the user has been disabled the name is displayed in grey but currently still links to the email page. I want these disabled users to not link.
I know that really I should be replacing them with a label but this does not seem quite as elegant as just removing the linking ability usings CSS say (if thats possible). They are already displayed in a different colour so its obvious that they are disabled users. I just need to switch off the link.
This sounds like a job for JQuery. Just give a specific class name to all of the HyperLink controls that you want the URLs removed and then apply the following JQuery snippet to the bottom of your page:
$(document).ready(function() {
$('a.NoLink').removeAttr('href')
});
All of the HyperLink controls with the class name "NoLink" will automatically have all of their URLs removed and the link will appear to be nothing more than text.
A single line of JQuery can solve your problem.
I'm curious on what it is you which to accomplish with that. Why use a link at all?
Is it just for the formatting? In that case, just use a <span> in HTML and use stylesheets to make the format match the links.
Or you use the link and attach an onClick-Event where you "return false;" which will make the browser not do the navigation - if JS is enabled.
But: Isn't that terribly confusing for your users? Why create something that looks like a link but does nothing?
Can you provide more details? I have this feeling that you are trying to solve a bigger problem which has a way better solution than to cripple a link :-)
A Hyperlink control will render as a "a" "/a" tag no matter what settings you do. You can customize a CSS class to make the link look like a normal label.
Alternatively you can build a custom control that inherits from System.Web.UI.WebControls.HyperLink, and override the Render method
protected override void Render(HtmlTextWriter writer)
{
if (Enabled)
base.Render(writer);
else
{
writer.RenderBeginTag(HtmlTextWriterTag.Span);
writer.Write(Text);
writer.RenderEndTag(HtmlTextWriterTag.Span);
}
}
}
Could be a bit overkill, but it will work for your requirements.
Plus I find is usefull to have a base asp:CustomHyperlink asp:CustomButton classes in my project files. Makes it easier to define custom behaviour throughout the project.
If you merely want to modify the appearance of the link so as not to look like a link, you can set the CSS for your "a" tags to not have underlines:
a: link, visited, hover, active {
text-decoration: none;
}
Though I would advise against including "hover" here because there will be no other way to know that it's a link.
Anyway I agree with #pilif here, this looks like a usability disaster waiting to happen.
If you mean to stop the link from activating, the usual way is to link to "javascript:void(0);", i.e.:
foo
This should work:
onclick="return false;"
if not, you could change href to "#" also. Making it appear as a rest of text is css, e.g. displaying arrow instead of hand is:
a.dummy {
cursor:default;
}
Thanks for all the input, it looks like the short answer is 'No you can't (well not nicely anyway)', so I'll have to do it the hard way and add the conditional code.
If you are using databind in asp.net handle the databinding event and just don't set the NavigateUrl if that users is disabled.
Have you tried just not setting the NavigateUrl property? If this isn't set, it may just render as a span.
.fusion-link-wrapper { pointer-events: none; }
Another solution is apply this class on your hyperlink.
.avoid-clicks {
pointer-events: none;
}
CSS solution to make tags with no href (which is what asp:HyperLink will produce if NavigateURL is bound to null/empty string) visually indistinguishable from the surrounding text:
a:not([href]), a:not([href]):hover, a:not([href]):active, a:not([href]):visited {
text-decoration: inherit !important;
color: inherit !important;
cursor: inherit !important;
}
Unfortunately, this won't tell screen readers not to read it out as a link - though without an href, it's not clickable, so I'm hoping it already won't be identified as such. I haven't had the chance to test it though.
(If you also want to do the same to links with href="", as well as those missing an href, you would need to add pointer-events:none as well, since otherwise an empty href will reload the page. This definitely leaves screen readers still treating it as a link, though.)
In the OP's use case, if you still have the href being populated from the database but have a boolean value that indicates whether the link should be a 'real' link or not, you should use that to disable the link, and add a:disabled to the selector list above. Then disabled links will also look like plain text rather than a greyed-out link. (Disabling the link will also provide that information to screen readers, so that's better than just using pointer-events: none and a class.)
A note of caution - if you add these sorts of rules globally rather than for a specific page, remember to watch out for cases where an tag has no (valid) href, but you are providing a click handler - you still need those to look/act like links.