For an existing site, I have to pass values in hidden fields from a form that's loaded by different pages (eg. City1.aspx, City2.aspx, City3.aspx, etc.), but they are loaded inside an iframe. I also have to dynamically change the value of at least one of those hidden field (let's call it "source") based on the city page loading it. I am familiar with PHP and JavaScript/JQuery, but I have no idea how to do this in C#.
I've found tutorials on retrieving the file name (sans extension) via JavaScript. I think I can still get the city even if the form is in an iframe, but I'd like to keep to the site's conventions and use C# if possible.
Code snippets or links to possible solutions would be much appreciated.
if you want modify the value of your input in c# associated to your aspx (Code behind), you must to add attributes runat=server to your input.
use this code in your aspx
<input id="test" type="hidden" runat="server"/>
and in your c#
test.Value = 123; //your value is 123 for example
Disclaimer, I don't know JQuery, so there could be easier ways to do this. I also haven't tested any code...
If you know the exact ID then you can do something like this from the parent page (in a javascript block):
var frame = document.getElementById('myIFrame');
var ctrl = frame.document.getElementById('myControl');
ctrl.value = "New Value";
If you don't know the exact ID's of the controls in the CityX.aspx pages, then you will either need a way for those ID's to be discovered, or you will need to go through all controls within the iframe looking for the correct one. (I say this because if the controls in the iframe pages are held in any sort of ASP.NET structure they will not be called txtMyCtrl (for instance) but possibly something like ct00_txtMyCtrl.)
If you don't know the EXACT control name (because of the ASP.NET structure I mentioned before), you could do something like:
var frame = document.getElementById('myIFrame');
var ctrls = frame.document.getElementByTagName("INPUT");
for(var i=0;i<ctrls.length;i++){
if(ctrls[i].getAttribute("type")=="hidden" && ctrls[i].id.indexOf("_myControl") != -1){
ctrls[i].value = "New Value";
break;
}
}
Or if you have the ability to update the CityX.aspx pages, then you could have the following in the CityX.aspx page:
function getCtrls(){
return [document.getElementById("<%=hiddenCtrl.ClientID%>"),
document.getElementById("<%=anotherHiddenCtrl.ClientID%>")];
}
... and then in your parent page, something like:
var frame = document.getElementById('myIFrame');
var ctrls = frame.document.getCtrls();
for(var i=0;i<ctrls.length;i++){
ctrls[i].value = "New Value";
}
They're just ideas on a general theme
Related
I retrieve some html codes from database and I want to display this values in a webform.
You can see my code below. It does not display labels and textboxes. However when I View the .aspx page source in the browser I can see retrieved labels and textboxes with Eval. Why I can not see labels and textboxes in the page?
database values:
code behind:
using (BurganEntities burganEntities = new BurganEntities())
{
List<DynamicField> dynamicFields=(from dynamicField in burganEntities.DynamicField select dynamicField).ToList();
cdcatalog.DataSource = dynamicFields;
cdcatalog.DataBind();
}
aspx:
The fast answer is because asp,net controls are compiled server side but you using them as text on the final render html page - so you have skip this compile, and the asp.net page did not know nothing about them.
The solution is to avoid asp.net controls and use regular html controls. You can still get their return on code behind, you may miss some easy to use functionality, but you can make your work with alternative way.
Other possible solution is to read the database and dynamically create the controls. For example you can add a flag on your database line that says, now create a text box, and on code behind you just create that text box dynamically.
Your code is simply outputting the <asp:TextBox /> to the browser; it isn't parsing it with the WebForms processor to convert it to an <input /> element.
In your database, you should probably be storing:
<input id="txtsdsd" name="txtsdsd" class="textbox" onkeypress="return NumberOnly()" />
and then using Request.Form() to retrieve the value.
I'm not sure if you've started to write your dynamic controls but as an addition to second reply, I would like to mention more sources about dynamic controls.
Although there is no concept of controls in ASP.NET MVC any longer, you can follow ASP.NET webform data access page.
As you want to compile your code at server side; on any postback you will loose dynamic content. So read this and all done.
Or as you mentioned you didn't get values of textboxes, please see the following method,
var textBox = FindControl("<id_of_textbox>") as TextBox;
if(textBox != null)
{
var textBoxValue = ((TextBox)textBox).Text;
}
</id_of_textbox>
see FindControl method at this page
So, I've seen many discussions that are in this area, but it seems like they are mostly discussing Windows Forms, or they don't get around to answering this specific scenario enough to point me in the right direction.
Exactly what I need to do (Generic Example):
HTML (fragment.aspx)
<div id="html_fragment_1" runat="server">Contents</div>
<div id="html_fragment_2" runat="server">Contents</div>
...
Code Behind (fragment.aspx.cs)
Fragments fragment = new Fragments();
fragment.return_fragment( AN INSTANCE THAT REFERS TO html_fragment_N );
Class (Fragments.cs)
public void return_fragment ( AN INSTANCE THAT REFERS TO html_fragment_N ) {
string html = INSTANCE.html_fragment_N;
// DO SOMETHING WITH html
HttpContext.Current.Response.Write(html);
}
The reason I need to do this is that every aspx form on my site needs to be manipulated in the same way by Fragments.return_fragment(), where the content for several DIVs need to be read from the Form and arranged into an XElement to be returned.
Instead of doing the manipulation in the CodeBehind for every page, I'd rather have each Form use Fragments.return_fragment() so that it saves effort implementing a new Form page, and the code can be changed easily without having to change it in each Form.
Looks like you want your app's Global.asax file:
http://msdn.microsoft.com/en-us/library/1xaas8a2(v=vs.71).aspx
Look at your app's page events here as a place to specify things that should happen on every page request.
I need to be able to set the IDs of dynamically generated labels instead of letting SharePoint prefix my labels with a long cryptic id of its own. Is this possible or is there another property of label that I can use as a unique identifier in a separate method?
Label animal = new Label();
animal.ID = cat;
The id for this label will be something like:
ctl00_m_g_e0c173c0_edf3_4a99_a1dd_7bef33144c0b_ctl00_cat
I need it to be cat.
To force the client-side id to be the same as the server-side id, use:
animal.ClientIDMode = ClientIDMode.Static;
You cannot set the ClientId of a server control. It is a read only property.
The cryptic id you see is actually your control heirarchy.
If you're attempting to access the control with javascript and are using jQuery, you can just the various regex selectors:
$("label[id$='cat']")
That will look for a label element with an id that ends with 'cat'
If your javascript is in the aspx file, and not a js file, you can also access it like so:
$('#<%=cat.ClientID %>')
That will just inject that long id created by Sharepoint into your js. Key is it needs to reside in the aspx file, not a js file.
I have made an application in javascript using HTML fields in asp.net, as asp text boxes were disturbing the ids, so i used html fields, which are working fine with javascript, now i want to fetch database table columns on page load, and want to assign to html fields, what is the best way to do so? Help me!!!!
You could go back to using the ASP TextBoxes and access the ids in JavaScript as follows:
<%= IDofTextBox.ClientID %>
It's probably the easiest as naturally they can then be accessed in the code behind very easily.
you can use asp text boxes fine if you grab a reference in your javascript to their asp.net generated ID via <%= textboxname.ClientId %>
This is not the right way to do it (I wouldn't recommending it), but if its what you need, then it will work.
Add method="post" action="<your path here>" to your form element and when the submit button posts, you will be able to access all the form variables like so:
string txtName = Request["TextBox1"] ?? string.Empty; //replace textbox 1 with text box name
Just be sure to replace the action in form to your page etc..
But really, going back to <asp:TextBox... will save you a lot more time and as Ian suggested, you can access them with javascript by the server tags <%= TextBox1.ClientId %>
ps: also, the ?? is a null coalesce character. its a short form of saying
if(Request["textbox1"] != null)
txtName = Request["textbox1"];
else
txtName = "";
If I understand you correctly. You just need to add runat="server" and id="someName" to the html fields and access them in the code behind by its given id.
I have a Search.aspx page which calls UCSearch control. UCSearch control does everything like getting what is being searched and what should be displayed, etc. I am trying to give the title to the page. As i dont have any info to write the code in the aspx page, i am thinking to write it in the control. But it is not displaying me when i tried using Page.Title in control. What am i doing wrong?? This is in Asp.net and C#.
Page.Title = "Search Results for Newark, NY";
Thanks in advance!!
Does not:
this.Page.Title = "My beautiful title";
work?
You should be able to get to the ASPX using the Parent property of the control. Cast that property to a Page (it's a WebControl or something similarly generic), then set its Title property. If you have a hierarchy of master pages or are nesting this control in other controls, you may need to traverse the Parent hierarchy for a few more levels.
You could also fire an event from your user control, passing the Title that you would like to display. You could then handle this event on the page, and set the title.
This does require a small amount of code in your aspx page, however, at least now the user control does not care where the title goes, the parent of the control can worry about it. If ever you want to change where this title goes, or even put it in multiple places, you don't have to change the user control. Let me know if you want a sample, I'll add it.
If you don't like that idea, then cederlof's answer will work, I just tested it.
protected void helloBtn_Click(object sender, EventArgs e)
{
this.Page.Title = "hello from control";
}
** You can use naming container to find the parent control of the current control. Through this way you can move through the page hierarchy.
Quickwatch will help you a lot in figuring out the things and building the statement for quick casting. Do some more research on naming container.
var container = userControl.NamingContainer;
if(container is Page)
{
Page p = container as Page;
p.Title = "Your Title";
}
**
Above is not the exact solution, but can help you it you can usercontrol directly on the page. Unless you need to iterate through the page controls. This was just for an quick help.