I realize this is probably a fundamental thing I should know but I am self-teaching myself C# and asp.net so I am a little lost at this point.
I right now have 2 pages. One is an .aspx (with aspx.cs file included) that is blank and html is generated for it from a Page_Load function in the cs file. The HTML is very simple and it is just an image and some text.
The second file is a shtml file which has lots of things, serverside includes, editable and noneditable areas. I want to put my webapp into this file. My asp.net app uses Response.Write to just write out the html. This does not flow well with this page as all that does is write it at the top of the page which is because it is ran first and generates it at the top.
How can I make it to where I can generate HTML code inside the page, like within a specific DIV so it does not mess up the page. Where would a starting point be in learning how to do that.
I should note that I do not need any interaction from the user. All of this should generate right away.
I think you need to read up on some basic ASP.Net documentation and tutorials. Response.Write is not the correct approach - you need to understand how the ASP.Net page lifecycle works and how WebControls are used to render the html.
ASP.Net tries to abstract away having to create your html manually for the most part.
So if i have understood the questions correctly.
You already have an existing page/application (the shtml file) that you want to extend with some new ASP.NET components by including output from the ASP.NET page in the existing page?
This is as not something that is out of the box "supported" by ASP.NET and you "won't" be able to execute the aspx page using SSI. But you can do the opposite, an ASP.NET page does support SSI. So if you are not using any other scripts in the shtml file this might be a solution.
Otherwise the only common solutions would be either to use an AJAX framework and let it call the ASP.NET from within the existing pages or to use an iframe solution. In both cases the client will be resposible for making the calls to the ASP.NET pages and merging the results.
And then you have a issue with controlling the output from the ASP.NET page?
The Polymorphic Podcast has a good article on Controlling HTML in ASP.NET WebForms .
You can add a Literal control to the page inside the div:
<div>
<asp:Literal ID="litMarkup" runat=server />
</div>
then in your code-behind:
litMarkup.Text = "<strong>Your markup</strong>";
I don't know how well this would work for you, but could you try using an iframe to house the ASP.NET page? This should keep it in the specified region and not overwriting your shtml file. It may be something to think about.
If it is necessary that you generate your HTML output from C# code, and you would use this in more than one place, I think you may be thinking of something like what are called ASP.NET Custom Controls (not to be confused with "User Controls"-- though you probably could put together a solution with those as well, using a Literal control as another person suggested). The MSDN documentation would be a good starting point. In general, though, the writing-out-HTML-yourself-from-code model (like you would with, say, CGI applications), is not the usual ASP.NET model of development, as it largely defeats the point of using ASP.NET at all. You'd mostly want to do this sort of thing if you are writing your own web control, though this might be exactly what you are doing (hard to tell from the description).
Related
I'm liking the Razor syntax that Microsoft has developed for inline coding in their WebMatrix product (http://en.wikipedia.org/wiki/Microsoft_WebMatrix).
Now that Visual Studio SP1 has RTM'd, is it possible (and/or planned) to enable the use of Razor syntax in ASP.NET Webforms?
We (the ASP.NET team) currently have no plans to support the WebForms page model using Razor syntax. Furthermore it is unlikely that we would ever seriously consider this as the models are too different to make the two work together.
You can use Razor pages without MVC; this is called ASP.Net WebPages.
Just add .CSHTML files to a normal ASP.Net 4.0 project.
I explained how this works in my blog.
You could possibly integrate it using the RazorEngine available from Codeplex. It allows you to process razor outside of MVC. Though you don't get all the features you get from the MVC version of Razor, such as #Html and #Url and others.
I dare say that Microsoft have considered it, but there is no official word on the subject. Since you are not supposed to have C# or VB code in the ASPX file, you have to wonder about the point of adding Razor support to Web Forms. The code behind would still be a (partial) class file. You wouldn't put Razor there any more than you would put it in a class file in Web Pages or MVC. And swapping Server Controls and all that good declarative stuff for Html Helpers removes one of the key reasons for going the Web Forms route, IMO.
This really isn't that difficult to do. Working on it right now. Grab RazorEngine from CodePlex. It lets you compile Razor cshtml/vbhtml files into a class at runtime.
You can then take that class, and use it from a ASP.Net server control, inside its Render method. This is a great way to get HTML out of the body of a server control. Much, much cleaner.
Now, you can also add some methods that you can invoke from Razor. For instance, add something like RenderChild. Additionally, you could set the Server Control itself as the Model available to Razor. You could then invoke into the server control. Including doing something like grabbing one of it's child controls and invoking Render.
I have googled this with a couple of differing terms and I could not find my solution. What I want to do is to manipulate a webpage by editing its source, for example removing a part from the code maybe a div or so. I know how to get the source of a webpage and know how to change the code but I have no idea how to manipulate the page instantly, by for example removing an element.
Your help would be appreciated!
If you want to manipulate client code (HTML) what you need is Ajax.
You can use JQuery javascript library to manipulate html of a page adding, editing and removing html tags, scripts, etc.
Here you can find a decent tutorial as a start point.
If you want to manipulate server code (C# codebehind) what you need is creating a web project in visual studio (ASP.NET Web Application)
EDIT: As commented by #CSharpened both solutions are not mutual exclusive. You can have an ASP.NET Web application that uses Ajax to manipulate UI. In fact lot of people does that.
I would consider using AJAX. You can use either javascript or jquery coupled with html, asp.net and C# to achieve the results you are after.
For simple editing like removing divs or collapsing menus etc simple Javascript or jquery will suffice. However changing the coding of the page requires you to use AJAX or similar.
I've got a aspx and aspx.cs file with some components. Now I want to reuse parts of that page in another page. My approach would be to pull out the duplicate part into a WebServerControl.
So before I waste more time yahoogling, is that even the right idea and if so, is there a way to use parts of the aspx file rather than doing it tediously in RenderContents with the HtmlTextWriter, WriteBeginTag, WriteAttribute and so on. That looks like a mess for complicated layout and sizeable amounts of controls.
What's the standard?
Depends.
The main driving factor is that if you need to reuse your control in multiple web applications, you should go with a Custom Control (.cs in C#).
Else, if you only intend to reuse your control in one web application, choose a User Control (.ascx).
This MSDN article is a good starting point.
UPDATE (since OP asked further details):
To embed JavaScript for a custom control, a common approach is
var initializeScript = string.Format("MyNamespace.initialize('{0}', {1});", ClientID, myScriptString);
Attributes.Add("onmouseover", initializeScript);
Suggest to write JavaScript code in a js file and not in .cs since the latter is a nightmare to maintain and debug. Hope this helps.
It sounds like what you want to do is bundle the items into a User Control. This will allow you to design the control by using existing .NET controls rather than rendering everything out from scratch.
All you need is to create an ASP.NET Web User Control
Taken from MSDN:
An ASP.NET Web user control is similar to a complete ASP.NET Web page
(.aspx file), with both a user interface page and code. You create the
user control in much the same way you create an ASP.NET page and then
add the markup and child controls that you need. A user control can
include code to manipulate its contents like a page can, including
performing tasks such as data binding.
I would like to know what is the best practice on separating the content of an aspx page (ASP.NET 3.5) from the code (I'm using C#). I have a form that users can type data in - for example they are allowed to enter a percent. If they enter data that's not valid they would get an error message:
<p class="errormsg" id="percenthigh">Please enter a percent below 100</p>
<p class="errormsg" id="percentnegative">Percent cannot be below 0</p>
<p class="errormsg" id="percentnot">This is not a percent</p>
So in essence I'm hiding the error messages and showing one depending on what the user input is.
I believe this is the best way to seperate the content from the code behind. However, how do I select elements and hide/unhide them depending on the user input? I'm aware I can do a runat="server" on the elements but the problem is that I can't select by class and am limited only to ID's.
What workarounds do you recommend? Aside from putting in the values in code behind which is notoriously difficult to debug.
Also has this been "fixed" in ASP.NET 4? And I'm interested in doing this only via C#/ASP.NET as some people have JavaScript disabled. This means that I would have to check errors on both client side and server side.
Use an ASP.Net Validation control for this. That will take care of the wiring in the code for you. You use a different Validation control for each of the paragraph tags in your question.
You should take a look to asp net validators. In most of the cases these are good enough.
If ASP NET validators are not suitable for any reason you could check a jQuery solution like this one
In any case, I'd recommend you to avoid spending time solving problems already solved in many different (good) ways.
Selectionm should be by ID when you want unique elements, ID should be unique across all of your elements. Class is used like a type in HTML, and is generally used for styling.
Also, text in asp.net projects should be saved in resource files. This allows easy changing of languages.
Is there a c# command to include another web page - the equivelant of the php require?
I know how to do server side includes but was looking for something code based.
Thanks
Thanks for the answers all. I think I might need to explain further. I have several sub-pages that I will be loading during the use of the site using an xmlhttp request. Initially however, I need to load the starting sub-page before the user has interacted with the site. I could do this with js, but that would require more overhead in server calls from the client for the initial load. I already use master pages, but this is a little different. Since this is done serverside initally but must remain able to be refreshed clientside, I don't think I can make these pages into controls can I? I am pretty new to .Net so I may be making my life harder than I need to.
I think what you may be looking for are MasterPages and UserControls. A MasterPage allows you to define a basic template that is "filled in" by the implementing pages by having the implementing page add it's own content to the ContentPlaceHolders defined on the MasterPage. A UserControl is a re-usable piece of markup and associated code that you can reference from your mark up or add dynamically to the page being rendered in codebehind.
The way ASP.NET is structured, you shouldn't really need to do this. Code is compiled, so all of your classes and functions should be accessible simply by referencing the relevant assembly or namespace, without having to include individual code files.
You might be looking for user controls, which allow you to create fragments of markup with their corresponding code behind, and then reference these in your page.
With ASP.NET MVC it looks like this:
<% Html.RenderPartial("LogOnUserControl"); %>
This way you can put another UserControl on your page.
you can use include in asp.net like php include from below mentioned code
<!--#include file="include/leftmenuscript.inc"-->
You can also use a master page, as someone stated below, which flushes out your basic layout and lets you define content place holders, which other pages can implement and fill in the content. Master pages are a popular approach for defining page elements that are consistent across all pages, like your nav there (also things like headers, footers, common scripts, CSS, etc.).