I am trying to use an MVC Partial to render a JavaScript grid. To do so, I have to load & utilize jQuery. However, I keep getting the following error:
$ is not defined
This should be simple...but apparently...it isn't.
THE PARTIAL LOOKS LIKE:
<h2>Inside the Partial</h2>
<div id="grid"></div>
<script type="text/javascript" defer>
// ERROR: $ is not defined
$(document).ready(function () {
// Awesome JavaScript Grid Stuff Will Go Here
});
</script>
THE VIEW LOOKS LIKE:
#using Web.Areas.Administration.ViewModels
#model LookupsViewModel
<h1>View Title</h1>
#Html.Partial(Model.PartialPath, Model.PartialModel)
Here are two main things that will help you solve your problem.
Make sure that your reference of the jQuery files is correct. Most you could had problem in the path.
Don't ever put JavaScripts in the partial views. Put those in parent view before the partial view where it has been called.
If you're loading jquery through script after the Partial view, you will be trying to run jquery variables before they are loaded and defined. Ensure that any jquery that you run (whether inline or not) is run after the page has requested and loaded jquery itself.
See: Can you write jQuery code inline before loading jQuery?
I'll give a bit more reason why you shouldn't put javascript in your partial views. If you use the Partial more than once, you risk having repeated javascript. That could mean variables are redefined, eventlisteners are added more than once, etc. causing some confusing bugs.
Related
I am working on a Umbraco 7 project started without MVC implemented. I try to implement a loading without page refresh. I am stuck now because I need some Razor code to get Umbraco information but I need jQuery to refresh without page refresh.
Here my code:
$(function () {
$.ajaxSetup({
cache: false
});
$('#filterButton').click(function(){
$('#content').html(#Html.Partial("~/Views/Partials/Preferences.cshtml"));
})
});
I tried with .load()with .html using #Html.Action,#Html.Partial etc, but nothing works. I know it is really simple to link a controller to an action like this but it will take me to much time now to change everything.
Can you say me if it is possible or not?
Please jquery try
$('#content').load("/Partials/Preferences");
another html helpers try
#{
Html.RenderAction("Preferences","Partials");
}
Syntext For
#Html.RenderAction(Action, Controller, Route)
Two partials loaded on the same page
For example, if I hit a button in one partial then I want some value to appear in the other partial.
I want all the work to be done on the client side. I am sure I would call a method in js but I am not sure how to connect it to another js var on another partial within the same page. In other words how do I get both the partials to talk to eachother on the client side.
Once your razor view is rendered to the browser, It is just HTML markup. That means, you can use javascript to access the elements in the DOM and update the values as needed.
Keep your script in the main view which holds the 2 partial views.
$(function(){
$("#ButtonInFirstParial").click(function(e){
e.preventDefault();
$("#DivInSecondPartial").html("Updated");
});
});
Also if you declare your javascript variable in a global scope, you can access it in other places also. So if you have a variable like this in your layout page,
<body>
#RenderBody()
<script type="text/javascript">
var global_SiteUrl="Some value i want to access in all pages";
</script>
</body>
You can access it in other views (which uses the above one as the Layout), or js files which are a part of other views who has the layout value set as the above layout.
I have many HTML helper in Helpers.cshtml file, but some of the helper (html) need some jquery action, so how do i can call jquery inside helpers.cshtml, is that possible?
i know we can keep the js file in header or particular page, but i do not want to do like that, i want to use jquery or javascript only on the page which loaded particular helper.
anyone have idea on this?
My scenario is, i have list box control, that is properly loading from helper, but i need to apply custom theme to the list box.
Little more Clarity
//in index.cshtml
#Helpers.testListBox("mylist" "1,2,3,4,5,6,7")
//in Helpers.cshtml
#helper testListBox(string listName, string listData){
//...... HTML code .........
//Javascript here?
}
With Web Forms, the framework could automatically include Javascript (once) when certain server controls were used on a page; ASP.Net MVC has no such facility. It sounds like this is what you're missing.
The way to do it is on the client. Look at RequireJS at http://requirejs.org/. This is a client-side library for managing Javascript dependencies. This does what Web Forms did, but better, and it does more. Your master layout will have a script tag like this:
<script src="/Scripts/require.js" type="text/javascript" data-main="/Scripts/main"></script>
This can be the only script tag you include on every page. Everything else can be dynamically loaded only as needed by RequireJS. It's true that you load this on every page, but it's smaller than jQuery, and it earns its place because it does so much for you.
Using your example, let's say you have this markup:
#Helpers.testListBox("mylist" "1,2,3,4,5,6,7")
and it renders HTML and needs jQuery scripting. You would render this:
// HTML for list box here
<script type="text/javascript>
require(['jquery'], function($) {
// Do your jQuery coding here:
$("myList").doSomething().whatever();
});
</script>
The require function will load jQuery, unless it has already been loaded, and then execute your code. It's true that your jQuery snippet is repeated once per use of the HTML helper, but that's not a big deal; that code should be short.
RequireJS manages dependencies effectively; you can have module A, and module B which dependes on A, and module C which depends on B. When your client code asks for module C, A and B will be loaded along with C, and in the correct order, and only once each. Furthermore, except for the initial load of require.js, scripts are loaded asynchronously, so your page rendering is not delayed by script loading.
When it's time to deploy your site on the web server, there's a tool that will examine the dependencies among the Javascript files and combine them into one or a small number of files, and then minimize them. None of your markup has to change at all. While in development, you can work with lots of small, modular Javascript files for easy debugging, and when you deploy, they are combined and minimized for efficiency.
This is much better than what the web forms framework did, and entirely client-side, which in my opinion is where it belongs.
You can put a <script> tag in the helper body.
How about this for an example of a partial view:
#model Member.CurrentMemberModel
#{
var title = "Test View";
}
<script type="text/javascript">
// Javascript goes in here, you can even add properties using "#" symbol
$(document).ready(function () {
//Do Jquery stuff here
});
</script>
#if (currentMember != null)
{
<div>Hello Member</div>
}
else
{
<div>You are not logged in</div>
}
I'm working on an application that uses asp.NET mvc3.
I created a partial view, and I call this partial view in a view, so that I can update a div without reloading the page.
I use setTimeout (but I also tried setInterval) to define the refreshing time.
The problem is that it does not work, it refreshes the div randomly, not following the time I set, and there is no logic that I can understand in it, sometimes it refreshes it twice, sometimes it waits, but never longer then the time I set.
This is the code of the partial view. In the View I just call the partial view.
<script type="text/javascript">
var st;
function updateDiv() {
st = null;
clearTimeout(st);
console.log("posting");
$.post('#Url.Action("RefreshSelfUpdatingPartial")', function (data) {
$('#SelfUpdatingPartialDiv').hide().slideDown("slow").html(data);
//wait 15 seconds
st = setTimeout(updateDiv, 15000);
});
}
updateDiv();
</script>
<div id="SelfUpdatingPartialDiv">
test
</div>
"This is the code of the partial view. In the View I just call the partial view."
If all of the above code is in the partial view, doesn't that mean that the $.post() is going to then load all of the above into the <div>, resulting in a second copy of the above nested inside itself? As the timeouts run it'll just keep nesting more and more copies inside itself.
I'd suggest you move all of the above into your main view, then the partial view should return only whatever text you want to see in the <div> (and no JavaScript).
(If that's not what you meant by the statement I quoted then please update your post to explain more clearly where the above code sits and what the $.post('#Url.Action("RefreshSelfUpdatingPartial")) actually returns.)
(Plus, like Alex said, don't set your st variable to null before you pass it to clearTimeout() - though I think you can delete both lines because you don't need to clear a timeout after it's already triggered.)
So I have a Layout page
<head>
#RenderSection("HeaderLast", required: false)
</head>
A view
#section HeaderLast
{
<script src="#Url.Content("~/Scripts/knockout-1.2.0.js")"
type="text/javascript"></script>
}
<div id="profile-tab">
#{ Html.RenderPartial("_userProfile"); }
</div>
And a Partial view
#section HeaderLast
{
<script type="text/javascript">
alert('test');
</script>
}
<div......
I figured it couldn't be that simple. Is there a proper way to do this out of box or will this always require some kind of mediator and passing stuff around ViewData to manually make the content bubble up to the layout page?
Bounty started: The bounty will be rewarded to the best solution provided for this short coming. Should no answers be provided I will award it to #SLaks for originally answering this question.
You cannot define sections in partial views.
Instead, you can put the Javascript in ViewBag, then emit any Javascript found in ViewBag in the layout page.
#JasCav: If a partial needs its own CSS, it has no good way to get it rendered.
If that's the reason for its use, it could very well be by design.
You don't want to have a separate CSS file x partial/helper. Remember, each separate CSS file means a separate request to get it from the server, thus an additional round-trip that affects time to render your page.
Also you don't want to emit direct CSS to the HTML from the partial/helper. Instead you want it to have appropriate hooks you can use to define all the look in your site's CSS file.
You can use the same hooks you have available for CSS to activate custom JavaScript behaviors for the elements involved When JavaScript is enabled.
Finally it may be the case what you need is not a Partial View, but an extra Layout you use for some pages. With that approach you would have:
A master Layout that gets set automatically on _ViewStart like you probably has now. This defines the sections like in your sample.
A children Layout page. Here you have both the extra html, css, js you need to have for these views. This uses both #RenderBody() and #section SomeSection { } to structure your common extra layout.
Some views that point to the children layout, and others that use the default master layout.
How to get extra data to the children Layout is out of the scope of the question, but you have several options. Like having a common base for your entities; using ViewBag or calling Html.RenderAction to get that shared logic related to shared dynamic elements in the layout.
It looks like there was a similar question on SO - How to render JavaScript into MasterLayout section from partial view?.
Unfortunately, there is no possibility of declaring sections inside Partial Views. That is because RenderPartial ends up rendering totally separate view page. There is a workaround to this, though a bit ugly. But it can look better if using strongly-typed model instead of ViewData.
Basically, you need to keep track of the reference to the view which called RenderPartial and use the DefineSection method on the object passed to push data to that view.
UPDATE: There is also a blog post about dealing with RenderSection you may find useful.
Here is another approach using helper methods and templated delegate
http://blogs.msdn.com/b/marcinon/archive/2010/12/15/razor-nested-layouts-and-redefined-sections.aspx
As a follow up to my question, the JavaScript/CSS combiner/minifier tool Cassette supports this functionality to allow you to compartmentalize your JavaScript and other assets that are required for partials.
I purchased a site license and use this in all of my MVC applications now.