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New Post: Validations and Feedback user

grahammendick — Wed, 13 Feb 2013 21:37:58 GMT

Hi Pablo,

It's always great to be asked a question, but it's especially nice when it's as complimentary as yours.

The Navigation framework doesn't provide any validation framework, but I'll try and explain the ASP.NET data binding way to do EF validation in an N-tier project. Let's assume you've got a FormView that's data bound to an Update method in your EmployeeController class. How do you communicate EF data validation failures on your Employee class back to the UI?

Before VS 2012 the only way was to have your Update method throw an Exception if the validation fails. Then your code behind could listen to the FormView's ItemUpdated event, check for the exception and set the KeepInEditMode on the FormViewUpdatedEventArgs passed in. This is messy. But the good news is that data binding has been overhauled in VS 2012. Now there's no need to throw Exceptions or add code behind because it can all be handled using the new ModelState parameter passed into your Update method.

Are you able to use VS 2012? If you can then there's no need to use ObjectDataSources for data binding any more. But I'll assume you can't use VS 2012 when answering your second question.

The first stage when using the Navigation framework is to create your StateInfo configuration because this contains the details of your pages. So, we'll create an Employee Details State:

<StateInfo>
    <dialog key="Employee" initial="Details" path="~/Details.aspx">
        <state key="Details" page="~/Details.aspx"/>
    </dialog> 
</StateInfo>

Then in your Details.aspx you need to add a FormView with it's DataSourceID property set to the ID of your ObjectDataSource control:

<asp:FormView runat="server" DataSourceID="DisplaySource">
    <ItemTemplate>
        <%#: Eval("Name") %>
    </ItemTemplate>
</asp:FormView>
<asp:ObjectDataSource ID="DisplaySource" runat="server" TypeName="Employee.Controllers.EmployeeController" SelectMethod="GetEmployee">
    <SelectParameters>
        <nav:NavigationDataParameter Name="Id" />
    </SelectParameters>
</asp:ObjectDataSource>

Then your GetEmployee method would look something like this:

public Employee GetEmployee(string Id)
{
    return new Employee() { Name = "Pablo" };
}

The Id passed into the GetEmployee method is currently empty but that's because we haven't passed any Navigation Data. This would probably be passed in from a previous page when an Employee is selected from a list. Would you like me to show how this is done?

There's more documentation on the Navigation framework than you might think. I've written quite a lot of articles and built various samples about it. Would you like me to provide links to some of them?

I really hope my answer has helped you.

Thanks,
Graham

New Post: Validations and Feedback user

pabloxenn — Tue, 12 Feb 2013 22:23:06 GMT

Congratulations. I really like "Navigation for ASP.NET Web Forms", I think it's a natural evolution of web applications and would like to learn and use it. I worry that there is little documentation and little information on the web but I will try. :)

I'd like to incorporate it into a project N-Tier with EF, where data validations like them at the server level, the question then is: How I can do this?, The other question, assuming I have ObjectDataSource and use NavigationDataParameter, this being a ref parameter, as follows:

<asp:ObjectDataSource ID="DisplaySource" runat="server" TypeName="Employee.Controllers.EmployeeController" SelectMethod="GetEmployee">
<SelectParameters>
<nav:NavigationDataParameter Name="errorMessage" />
</SelectParameters>
</asp:ObjectDataSource>

public Employee GetEmployee (ref string errorMessage), how I can implement it?

Thanks in advance, Pablo

New Post: Using SSL

spryguy — Tue, 21 Aug 2012 20:54:27 GMT

I believe that must have been a different spryguy. Thanks for the suggestion.

New Post: Using SSL

grahammendick — Fri, 17 Aug 2012 16:32:38 GMT

I think the best place to enable Http to Https redirection is at the load balancer level. If you're not using a load balancer you could implement a URL Rewrite Module within IIS.

Are you the spryguy that asked that interesting question about my MSDN Magazine article?

New Post: Using SSL

spryguy — Wed, 15 Aug 2012 21:04:25 GMT

Has anyone attempted to use this with SSL? I would like to be able to use SSL to capture some credit card info and then pop back to HTTP.

TIA,

Ivan Brown

New Post: Too early for 4.5

rcollette — Thu, 02 Aug 2012 20:48:11 GMT

Very much appreciated.

New Post: Too early for 4.5

grahammendick — Thu, 02 Aug 2012 19:23:45 GMT

Thanks for getting in touch. I've added a link under the Documentation tab to a VS 2010 build of the demo project. I hope this is what you're after.

If there's anything else I can help with just let me know.

New Post: Too early for 4.5

rcollette — Thu, 02 Aug 2012 01:08:42 GMT

Vs 2012 isn't even released yet. I am unable to run the demo site in vs2010. Would you think about putting up a vs2010 build for those of us that work at companies that wait for the first sp to be released before adopting a new major release?

New Post: State passed in URL

grahammendick — Sat, 16 Jun 2012 18:16:22 GMT

It's great to hear you enjoyed the articles and thanks for sharing your concerns about the Navigation framework. Let's see if I can allay them.

When writing the MSDN articles I tried to come up with a sample project that demonstrated the different features of the framework in a straightforward way; but I agree with you that it wouldn't be appropriate to build a real online Survey in that way. However, that doesn't mean the Navigation framework can't still be used. The way to build a real Survey application would be to store the answers, as you say, in Session, but to still use the Navigation framework to handle the forward and back navigation. In that case, only the previous State(s) would appear in the URL and not the user's data.

I've taken this a stage further in applications I've written by storing the data in Session but still allowing the user to open multiple windows/tabs. The way I've done this is to maintain an id in StateContext Data that points to the specific instance of the user's data in the Session. Then it's just this id (and previous States) that appears in the URL and not the user's data. That way, you can have multiple instances of the user's data allowing them to complete two surveys simultaneously in different windows.

If you prefer, you can even configure the framework so that the crumb trail is stored in Sesssion rather than the URL or write your own custom crumb trail storage mechanism.

I agree that removing the crumbs is pointless if you want to make use of back navigation. However, there's more to the Navigation framework than back navigation. For example, it's really useful in building Single Page Applications where there's no point in having the crumbs in the URL.

I hope this gives you the idea that the Navigaiton framework has a lot more about it than I could explain in the articles and I look forward to hearing what you think.

New Post: State passed in URL

timmi4sa — Sat, 16 Jun 2012 16:40:04 GMT

Let me start by saying that I love your two articles in the MSDN Magazine - very fresh perspective! I have created one VS'10 solution per article to get a taste of the Navigation framework.

The URL Query for back navigation is a strange choice for just about _any_ type of app. I work in the healthcare industry and seeing patient's provided information that can be easily modified across several steps of the wizard seems unacceptable. Even any trivial tax preparation app, or college admissions or .. you get the point. So this is only useful for some code prototyping or home projects.

Removing the crumbs (trackCrumbTrail=false) as you suggested renders the framework nearly useless. What if I am prepared to prevent the user from opening multiple browser windows in order for the Navigation framework to store state in Session object, is there a built in support for that?

Great Start!!

New Post: State passed in URL

grahammendick — Thu, 14 Jun 2012 21:30:34 GMT

Thanks for an interesting question. I can understand where you're coming from but don't worry, the Navigation framework can be used in lots of different ways.

If you don't want to pass navigation/transition state information in the URL then you can set trackCrumbTrail="false" against each State in the StateInfo configuration. This would mean URLs would be completely clean, but be aware that back navigation then can't be used.

If you want logical URLs, the Navigation framework supports ASP.NET Routing. You can specify a route against each State in the stateInfo configuration.

<state key="s1" page="~/p1.aspx" route="r1" trackCrumbTrail="false"/>

It can even help you build Single Page Applications, where there is only one state and no transitions.

Let me know if you're still interested. If you need any clarification or have more questions, please just ask. Also, I could point you at some sample code/articles I've written that should help.

New Post: State passed in URL

MJackson — Thu, 14 Jun 2012 19:06:27 GMT

So far I love what I am seeing here. I am gettting ready to embark on some sample/test projects to continue to evaluate how this framework could help me. Though for some reason, passing the navigation/transition state information in the url isn't sitting well with me - I prefer clean, logical URLs. I worry about large/complex dialogs with many states and transitions. Do you have any words to calm my fears :) ?

New Post: Include other non-navigation pages

grahammendick — Tue, 11 Oct 2011 21:17:45 GMT

Thank you for your nice comments, I am glad you like it.

All navigation must be configured in the StateInfo configuration, this includes the links on the left side. Taking the navigation sample configuration, if you wanted to have a menu link to a Home page then you'd need to add another dialog:

<StateInfo>
	<dialog key="Person" initial="Listing" path="~/Listing.aspx">
		<state key="Listing" page="~/Listing.aspx" title="Person Search">
			<transition key="Select" to="Details"/>
		</state>
		<state key="Details" page="~/Details.aspx" title="Person Details" route="Person/{id}">
		</state>
	</dialog>
	<dialog key="Home" initial="Page">
		<state key="Page"  page="~/Home.aspx" title="Home"/>
	</dialog>
</StateInfo>

Then in order to link to your home page you can just add a NavigationHyperLink pointing at the Home dialog:

<cc1:NavigationHyperLink ID="HomeLink" runat="server" Text="Home" Action="Home" />

You might find it helpful to look at http://navigationnerddinner.codeplex.com/ as this is a more detailed sample.

I hope this has helped, let me know how you get on.

Graham

New Post: Include other non-navigation pages

BigFan — Tue, 11 Oct 2011 20:43:04 GMT

I am a newbie to this. I like your navigation app so much. I am thinking to use it to chunk up a long form into multiple pages. However, my project would have other pages that are not part of the wizard steps (links on the left side). I want to be able to navigate between pages that are part of the steps or outside them. Currently, if I try to navigate to another page, I would get this error: invalidURL.

Is there a way to accomplish this? Am I missingsomething? Please help

Thanks

New Post: have you ever tried to pass Custom NavigationData?

rob_alarcon — Wed, 20 Jul 2011 22:24:37 GMT

Thank you very much for your quick answer, you were right, I have my custom navigation data working.

New Post: have you ever tried to pass Custom NavigationData?

GrahamMendick — Wed, 20 Jul 2011 08:43:01 GMT

Hi,

Thanks very much for the question and I'm really glad you like the code.

Your sectionGroup is where the error is, it should read as follows:

You don't need to register your PersonConverter class in the configuration as long as it is specified through the TypeConverter attribute on top of the Person class:

	[TypeConverter(typeof(PersonConverter))]
	public class Person
	{
	}

I hope this helps,

Graham

New Post: have you ever tried to pass Custom NavigationData?

rob_alarcon — Wed, 20 Jul 2011 02:03:00 GMT

I created a simple class and it's converter add the register in the web.config something like this:

...

....

but my code fails here:

    public IEnumerable SearchWithCompletePerson() {
        return from p in _People
               select new {
                   p.Name,
                   p.DateOfBirth,
                   Link = StateController.GetNavigationLink("SelectWithCompletePerson",
                                                            new NavigationData()
                                                                           {
                                                                               {"foo", p}
                                                                           })
               };
    }

It says that my converter it's not implementing the

IConfigurationSectionHandler

but after implementing that interface I still have weird errors, and maybe I'm doing something very wrong.

Cool project by the way, cool code.