Is it possible to use #Html.RenderPartial inside #using(Ajax.BeginForm) code block?
It doesn't work if I use #Html.RenderPartial, and it works if I put whole of razor code directly inside #using(Ajax.BeginForm) block.
Could anyone please suggest if that's possible or not?
If the Html.RenderPartial is right after the #using(Ajax.BeginForm(...)) then you don't need to prefix the call to Html.RenderPartial with # as razor understands you are still in the same code block.
So, this works fine:
#using (Ajax.BeginForm(...)) {
Html.RenderPartial("_PartialView", Model);
<p>after partial view inside the ajax form</p>
}
If between the `#using(Ajax.BeginForm(...)) and the render partial you have some html, then razor will end the code block before you call RenderPartial and you will need to do this:
#using (Ajax.BeginForm(new AjaxOptions())) {
<div>
<h3>partial view inside the ajax form</h3>
#{ Html.RenderPartial("_PartialView", Model); }
</div>
}
Also notice that Html.RenderPartial is a method that returns void and internally calls Write, so the syntax for using it is slightly different than when you use Html.Partial, that's why you need to surround it with "#{" (when not in a code block already) and end it with semicolon. See this question
Related
While using #code, getting the error: The name Code doesn't exist in the current context
tried including namespace #using Microsoft.AspNetCore.Components.Web but not helping. Same code is working fine in Razor component but want to know how to make it work in Razor view. Searched online but cannot find any solution.
<input #bind="count" #bind:event="oninput" />
#code
{
int count;
}
above code should compile but throwing an error: The name Code doesn't exist in the current context
You don't need the word code, just
#{
int count;
}
For #code, it only applies to Razor components (.razor).
This scenario only applies to Razor components (.razor).
The #code block enables a Razor component to add C# members (fields,
properties, and methods) to a component
It is not supported in Razor View.
I am using razor to show/hide page content based on variables in the model:
#if (Model.TicketShown == null)
{
#:<div id="ticket-section">
} else {
#:<div id="ticket-section" style="display:none">
}
//More Code
#:</div>
I have been using it for a while, but today I am getting the error '"#" must be followed by a valid code block' just on the closing tag. I am using the syntax elsewhere and it works fine.
Why and is there a more elegant way of doing this? Thanks
#: is meant to be used inside code blocks (see Explicit line transition), your #:</div> might not be inside one. You could use Html.Raw as alternative (e.g. #Html.Raw("</div>")).
With the help of the ?: operator, you could also rewrite the if as follows:
<div id="ticket-section" style=#(Model.TicketShown == null ? "" : "display:none")>
...
</div>
I have written a tag helper that I can use as follows...
<mytaghelper attr1="jim"></mytaghelper>
I would like to be able to shorten this to just...
<mytaghelper attr1="jim">
...or at least...
<mytaghelper attr1="jim"/>
However, I can't get this to work. Here is some sample code for the Process method...
public override void Process(TagHelperContext context, TagHelperOutput output) {
output.TagName = "div";
output.PreContent.SetHtmlContent("<div>");
output.Content.SetHtmlContent("OUTPUT HTML GOES HERE");
output.PostContent.SetHtmlContent("</div>");
output.Attributes.Clear();
}
I have tried adding a TagStructure setting to the HtmlTargetElement attribute on the class...
[HtmlTargetElement("mytaghelper", TagStructure = TagStructure.WithoutEndTag)]
...but it doesn't seem to make any difference. <mytaghelper attr1="jim"/> generates <div /> and <mytaghelper attr1="jim"></mytaghelper> generates <div></mytaghelper>.
If I set the TagStructure to NormalOrSelfClosing then included a closing tag works, but <mytaghelper attr1="jim"/> gives an empty <div />
Anyone able to explain what I need to do?
TagStructure.WithoutEndTag is able to write the tag with only a start tag or self-closing, but the output would be <div > or <div/> . Self-closing anchor tags are not valid HTML, so you wouldn't want to create one, but you might want to create a tag helper that's self-closing. Tag helpers set the type of the TagMode property after reading a tag. Add the below code line Inside the process method:
output.TagMode = TagMode.StartTagAndEndTag;
Take a moment to read Author Tag Helpers in ASP.NET Core which covers this perfectly .
The correct syntax is:
[HtmlTargetElement("mytaghelper", TagStructure = TagStructure.WithoutEndTag)]
Which should be applied to the taghelper class, not the Process method. You may already be doing that, but it wasn't clear in your question. I believe you still must use the self-closing tag syntax (/>) for it work, though.
I have a partial view (_FormCustomer) that displays a form for creating a customer. I also have a View Component (Countrylist) that generates a options list of countries. Now I want to show the country list in my form. This is what I do:
Index.cshtml
<partial name="_FormCustomer" for="#Model._Customer" />
_FormCustomer.cshtml
<select asp-for="#Model.Land" class="form-control">
#await Component.InvokeAsync("Countrylist");
</select>
CountrylistViewComponent.cs
public async Task<IViewComponentResult> InvokeAsync()
{
return View(await _countryRepository.GetCountriesAsync());
}
(The function GetCountriesAsync() returns a list of countries; this works fine.)
Pages/Componenst/Countrylist/default.cshtml
#model List<Country>
#foreach (Country country in Model)
{
<option value="#country.code">#country.name</option>
}
Unfortunately, select-box stays empty when I call the partial. When I call #await Component.InvokeAsync("Countrylist"); directly from Index.cshtml, however, it works fine.
So it looks like you cannot use a View Component inside a Partial View. Is this conclusion right? Or am I doing something wrong?
Thanks Phantom2018, found the problem after your post.
#0: I'm using Razor pages
#1: this had no effect
#2: this was a typo in my question, not in my code
#3: the debugger shows me that the vie component gets called, so
My actual code is a little different, I want to pre select a country if it's available:
<select asp-for="#Model.Country" class="form-control">
#if (Model == null)
{
await Component.InvokeAsync("Countrylist");
}
else
{
await Component.InvokeAsync("Countrylist", Model.Country);
}
</select>
And after some testing, I found the solution:
<select asp-for="#Model.Country" class="form-control">
#if (Model == null)
{
#await Component.InvokeAsync("Countrylist");
}
else
{
#await Component.InvokeAsync("Countrylist", Model.Country);
}
</select>
Don't know why, but I had to use #'s before the awaits.
I have now tested this scenario and can confirm that the data loads fine - both, when the view component is directly included on the page or when it is included in a partial View. (I have tested this on Razor pages - but it is likely to work the same when using MVC. You have not mentioned if you are using MVC or Razor pages.)
A couple of things you can try to see if the loading works fine:
1) From all "Select"s and "Partials" remove the "for*" attributes. That way you can first check if the data loads & then you can worry about binding to the selected item. (Also, in your provided code, you have omitted the model variables - so it is not possible to comment on them.)
2) Remove the last ";" in your _FormCustomer.cshtml
<select asp-for="#Model.Land" class="form-control">
#await Component.InvokeAsync("Countrylist")
</select>
Note that I have removed the trailing ";" in the await statement. I noticed that the ";" was added as another "option" in the select !
3) I also noticed that even minor syntax errors (not picked up by Intellisense) can cause the select to not load. Debug to see if your InvokeAsync is actually being called - in a scenario where there was a minor syntax error, the InvokeAsync was not even being called.
Also keep in mind that:
"When a partial view is instantiated, it receives a copy of the
parent's ViewData dictionary. Updates made to the data within the
partial view aren't persisted to the parent view. ViewData changes in
a partial view are lost when the partial view returns."
I'm learning MVC and am stumped by this. I'm trying to factor some common code that gets data and displays it in a WebGrid into a partial view that i can use on multiple pages.
My home controller Index method just does a return View(). The Home view looks like this:
#using (Ajax.BeginForm("SearchAction", "Search",
new AjaxOptions { UpdateTargetId = "data-grid", HttpMethod = "Post" }))
{
#Html.TextBoxFor(model => model.name)
<input type="submit" value="Search" />
}
#{
<div id="data-grid">
#Html.Partial("SearchResults", Model)
</div>
}
I'm trying to use Ajax to avoid losing my search form data when clicking a WebGrid pager link, which are rendered as normal links.
My SearchController looks like this:
public ActionResult SearchAction(string name)
{
return RedirectToAction("SearchResults", new { name = name });
}
public ActionResult SearchResults(string name)
{
//does database query and sticks results in the viewbag
//filter on optional name parameter
VieweBag.Members = MyQueryResults;
return PartialView();
}
My SearchResults shared view, data is passed in via ViewBag.Members:
#{
var grid = new WebGrid(null, rowsPerPage: ViewBag.Pagesize);
grid.Bind(ViewBag.Members);
#grid.GetHtml(// etc. etc.)
}
The results I'm getting is that the ViewBag.Pagesize and ViewBag.Members binding fails since there is no data in the viewbag. Obviously, my partial controller is not being called to do the initial query and put stuff in the ViewBag when the home page is first loaded. How do I make that happen?
The other weird thing is that if I just copy the database query code into my home controller (where it originally was) to force the original query, then if I put some text into the search field and do a search, the partial view renders by itself on a new page. Why is that happening, I thought it would only render as part of my home page.
I've cobbled this partial view together from various answers/places and have no doubt gotten something horribly wrong :\
The partial page won't pass through a controller, but simply render the view directly. If you want to pass view data to the partial view, there is an overloaded function that takes a viewdata dictionary. I'm sorry I can't be more detailed, but I'm on my mobile (waiting for my son to fall asleep in the other room) :)
Update:
If you want to trigger a GET action for your partial view, you can use Html.Action. Here are some useful links:
MSDN RenderAction
Difference between RenderPartial and RenderAction
Further, it would probably make sense for you to move your form tags into your partial view, but those are details for when you clean up the code.
Jonass is right, the ViewBag only propagates between the Controller and the View.
One thing you can do is make the model of the partial view be the same as the type of data you're putting into the ViewBag.
So if for example your MyQueryResults is of type:
IEnumerable<Result>
In your partial view you'd add
#Model IEnumerable<Result>
And then in the main view, you'd pass it through the Render method:
#Html.Partial("SearchResults", ViewBag.Members);
You'll need to tweak this a bit to make sure it's the right type, but this should do the trick.
Good luck!