I need to supply an html form (not a server form) for searching within an asp.net web-forms website. The form will post to another website where an indexed search is performed. Seeing as nested forms don't work well in asp.net, what is the simplest approach for this?
The nested form is a simple html form that performs a "get" against the search website, which I do not have programmatic control over.
Update: I resolved my issue by simply moving the server form to the appropriate place on the page, rather than having it surround the entire page. However, I'm still wondering how this would be handled if the html form needed to be placed physically between server controls (which require the server form).
However, I'm still wondering how this would be handled if the html form needed to be placed physically between server controls (which require the server form).
You can place controls on your page without requiring an HtmlForm.
In your case there's no issue declaring another form markup, but you could also just use some search control on your main form and make it issue a GET to that website.
Not only do nested forms "not work well," you basically can't have >1 form per page at all. The simplest approach is the approach you are forced to go with: write a page that only uses one <form runat="server"></form>. Since you need search functionality, is there no ASP.NET search box control that you could use?
Have a read here.
There are 4 workarounds:
Use an IFRAME
Force Submission to Navigate Using a GET Request
Dynamically Change the Form Action
Use a 3rd Party Form Handler
More details on http://www.revindex.com/Blogs/tabid/65/EntryID/21/Default.aspx
Nested forms don't work well in HTML full stop! You should never do it.
Perhaps you mean more than one form on page? Whilst it's true you can only have one form with runat="server", I can't see any reason why you couldn't have a standard form (not server form) that posted to another site at the same level (ie. not nested).
Try adding your HTML input elements to wherever you want the nested form to be. Then use JQuery to change the page form action to point to the external Website. The entire form is submitted, but with a different external Url. The minor downside is the values for all input elements on the page are posted, but most times that is not big deal.
(I only tried this using a POST, not a GET. This is basically Roman O's #3 workaround in more detail)
<div id="nested-form">
<input type="text" name="q">
<input name="searchbtn" value="Go" type="submit" class="search-button">
</div>
<script>
$(function() {
$("input.search-button").click(function() {
$('form').get(0).setAttribute('action', 'http://external.com');
});
});
</script>
maybe you try Server.Transfer() to your target page that do the search from a button for example!
Related
So far, all the web pages I met contain at most one <form> tag. Why not multiple ones? I can not think of reasons why multiple forms can't coexist within the same web page.
Also, to be specific to ASP.NET - why are all the server controls are placed within the <form> tag? Why not place them somewhere else?
Plus,
I noticed that in an .aspx file, the <form> tag has the runat=server attribute, while a normal server control such as Button also has one. So it seems the <form> is also a server control. But strangely enough, I cannot find it in the Visual Studio Toolbox.
There can be multiple forms, with hacks.
It is indeed a shortcoming of WebForms. In ASP.NET MVC you can implement as many forms as you want (and it is valid & correct behavior of web pages).
The reason all server controls are placed inside <form> tag is to allow the WebForms engine to recognize them, load their values & save their values from/to the ViewState. Almost all infrastructure of control management in WebForms is based on the idea that a tag contains everything you access from the code-behind.
As pointed out, this is one of the shortcomings of WebForms. I do want to point out, additionally, that with cross-page posting and validation groups, you can typically reach your desired behavior (for most "multi-form" solutions).
Regarding the additional question: the <form runat="server"> is parsed as HtmlForm class behind the scenes, which inherits from HtmlControl like any other HTML element with runat="server".
Unlike any other HtmlControl though, there can exist only one instance per page and it does not appear in the toolbox as it's added automatically to every new Form you create, so it's quite pointless.
Yes, it can be done - by creating a custom HtmlForm object and toggling the forms as needed. I've just answered a similar question here (with code):
Paypal Form Ruins My ASP.NET webforms layout -> How to Solve?
many non server forms - you can , but only one runAt Server form
i also found this :
A server-side form tag is the tag which has a runat="server" attribute. If this attribute
is missing, then it's a typical HTML form tag. The conclusion is that you are allowed to use
multiple form tags on a page, as long as only one has the runat="server" attribute. The
disadvantage of the form that doesn't have this attribute, is that view state won't work
(meaning form values will disappear when using the back/forward browser buttons). It's a
small price to pay if you really need multiple forms on a page.
Take master page & set design.
Take one form in master page.
Second form take in contain place holder.
In contain place holder in only for write form tag (not use)
Add aspx page & design second form but not write form tag only for control put
Take button click event fire code write
This is proper way of two form
When a client is on page A.aspx , and he press some button there is a postback.
The server knows which page to rebuild according to the request.
but how does the client knows which page to re-ask ? by the current url of his browser ?
where this information is saved in the client side ?
Its defined in the action property of <form>. The client does not need to re-ask, the server sends a response of his request.
ASP.NET is just a part of the .NET framework, but what every client sees on a web browser in plain old HTML.
ASP.NET gives you several controls that makes it easy to use them programatically, so we can set all sort of things in our code (that is run before the page is showing) to do the exactly what we want.
every link, button, image, grid, it's just HTML tags, like <a> for links, <input type="button"> for buttons etc...
Keep in mind that now, there are 2 variantes of the ASP.NET, the WebForms and the MVC (you can also read about choosing one in prole of the other)
in every ASP.NET WebForms there is always a <form> on the start of the <body> and wrapps all your code, so, any submit will do a PostBack into the same file name, in your example A.apsx will always post into A.aspx, then if you want, for example, send that request to B.aspx you need to have a Click Event that would use the Server.Transfer("B.aspx") and that would redirect the entire post to B.aspx just like it was a post from B.aspx
in the newest pattern, the ASP.NET MVC, it drives with Routes witch let's you set up any, every, one, multiple, ways to reach the same page. In MVC the URL does not point to a specific page, but to a specific Controller and it's up to the Controller to send, after processing the data, to a specific View, that is why in MVC there are no pages in the url (though you can add it to the route if you want, and you can accomplish the same with WebForms using a Routing plugin).
Now, in MVC it's there is no <form> wrapping up your entire code, you need to, if you want to submit something, create your own <form> and point to the correct route
but, just like in Webforms or any HTML page, posts are made through form submittion, and it's "path" it's always whats in the form attribute action that let's you know what's the next step.
I hope this helps you realizing that there is no big monster in ASP.NET, that is only a way to reuse controls and access them programmatically and that, in the end, it's all HTML :)
A general answer: on the client side it's either a submit from within a form or a link.
The form points to either a relative URL (that means the current URL plays a key role) or an absolute URL (the current URL plays little to no role).
For links it's generally the same: either they are relative or absolute. One big difference: links are use HTTP GET while forms can use HTTP POST (thus transferring more data without encoding them to the URL as parameters).
For a button it's the form that gets submitted.
So, when i was dealing with forms before what i would do is find web element that is part of the form input, set value of that form input by element.setattribute("value", "infoi want to add")
then simply when i set value of form elements i click submit button of form.
Is this possible to do with web-form input type="file" and how can i do it?
Thanks
The simplest and the most straightforward way to do exactly what you've described is to get form's target address with QWebFrame::hitTestContent and then to post a file with QNetworkAccessManager::post. You also could inject some javascript code into a loaded page (see this for more details), but that would be an overkill for such a simple taks. And besides in the latter case all your injected javascript will be gone after submitting the form (i.e. after the page is reloaded).
I realize that ASP.NET is only designed to support a single form. What I am confused about is what is the appropriate method for coding multiple "forms" on a .NET page (I have a login form at the top of the page, via the Site.Master and other forms will appear on any given page). Am I supposed to respond differently? It doesn't really make a whole lot of sense. I would appreciate it if someone could clarify. Thanks.
P.S. I am currently developing on .NET 2.0 although I plan to move to .NET 3.5 soon.
Nearly all ASP.NET Web Forms post back to the same page. Unless you are working on some strange outlier (which your question doesn't indicate), you just use one form tag around the entire document, and use event hookups to your controls to handle the various instances.
For example, you can have three buttons that act as Submit buttons, one for each "form" but all inside that same form tag, and each one will call its respective event. This behavior is standard and handled by ASP.NET for you; all you have to do is write the event handlers and wire them up.
I'm not sure what you mean by a logon form. Are you doing some special ajax stuff?
You should be dividing any logical "form" as you call it into its own usercontrol.
http://www.asp101.com/lessons/usercontrols.asp
When dealing with aspx pages, think of the form on the page the same way you think of the body tag.
In that case, I would hand-code the login form at the top to submit to a separate login.aspx page. Leave the rest of the page to the other form's own purpose.
by default you can't, it's how the whole webforms technology works (MVC would probobly fix this in the newest versions).
So really it depends on what you want the "two forms" to do. For example, there's no issue with having login & search on one page, as each button has its own click event and go from there. If you wanted a second aspx page to process one of them, you could collect values and pass them through a response.redirect or some other hacky solution.
I have a simple website and I use masterPage for designing my template.
everythings work fine, but when I add a Custom (google) Search Box in it my pages correpted.
infact asp does not support Nested Form and as you all know google use a simple form to get queries from the users.
so at first I redesign my site and put 2 Form in it. One server form for my pages content and one other form for google search box. untill here everything work fine .
so I force to add 2 new button beside of my search box and these buttons need a runat=server form, so now I need an approach that let me enable a third form (second runat=server form ) or find an approach to use simple form inside of runat=server form, actually
howcan I put 2 form inside each other or how could we enable a nested form ?
Nested forms won't be possible. You'll need to make those buttons work without being in a runat="server" form.
Cause Asp Forms are not a display control and just accessible in code for programmers,
so I use it in a unregular manner,
as you all know every XML markup like XHTML (asp) have some element (in asp case : control) and each element have its own attribute (in asp case controls properties)
so I just need to put my controls inside the Form (root) Element and cause when page loading on client machine, whenever browser see the server form just change a flag to true (the server form is available) then you can use what ever you have inside of the form,
so if you can lagically put your controls inside of the form , so putit, nothing bad happen )