我在我的_Layout.cshtml中定义了这个部分

@RenderSection("Scripts", false)

我可以很容易地从视图中使用它:

@section Scripts { 
    @*Stuff comes here*@
}

我正在努力解决的问题是如何从局部视图将一些内容注入到这个部分中。

让我们假设这是我的视图页面:

@section Scripts { 

    <script>
        //code comes here
    </script>
}

<div>
    poo bar poo
</div>

<div>
  @Html.Partial("_myPartial")
</div>

我需要在脚本部分中从_myPartial partial视图中注入一些内容。

我该怎么做呢?


当前回答

你可以使用这些扩展方法:(保存为PartialWithScript.cs)

namespace System.Web.Mvc.Html
{
    public static class PartialWithScript
    {
        public static void RenderPartialWithScript(this HtmlHelper htmlHelper, string partialViewName)
        {
            if (htmlHelper.ViewBag.ScriptPartials == null)
            {
                htmlHelper.ViewBag.ScriptPartials = new List<string>();
            }

            if (!htmlHelper.ViewBag.ScriptPartials.Contains(partialViewName))
            {
                htmlHelper.ViewBag.ScriptPartials.Add(partialViewName);
            }

            htmlHelper.ViewBag.ScriptPartialHtml = true;
            htmlHelper.RenderPartial(partialViewName);
        }

        public static void RenderPartialScripts(this HtmlHelper htmlHelper)
        {
            if (htmlHelper.ViewBag.ScriptPartials != null)
            {
                htmlHelper.ViewBag.ScriptPartialHtml = false;
                foreach (string partial in htmlHelper.ViewBag.ScriptPartials)
                {
                    htmlHelper.RenderPartial(partial);
                }
            }
        }
    }
}

像这样使用:

示例partial:(_MyPartial.cshtml) 把html放在if里,js放在else里。

@if (ViewBag.ScriptPartialHtml ?? true)
    <p>I has htmls</p>
}
else {
    <script type="text/javascript">
        alert('I has javascripts');
    </script>
}

在你的_Layout中。cshtml,或者任何你想要渲染的部分脚本的地方,放置以下(一次):它将只在当前页面的这个位置渲染所有部分的javascript。

@{ Html.RenderPartialScripts(); }

然后使用您的部分,只需这样做:它将只呈现该位置的html。

@{Html.RenderPartialWithScript("~/Views/MyController/_MyPartial.cshtml");}

其他回答

从这个线程中的解决方案,我提出了以下可能过于复杂的解决方案,让你延迟渲染任何html(脚本)在一个using块。

使用

创建section

Typical scenario: In a partial view, only include the block one time no matter how many times the partial view is repeated in the page: @using (Html.Delayed(isOnlyOne: "some unique name for this section")) { <script> someInlineScript(); </script> } In a partial view, include the block for every time the partial is used: @using (Html.Delayed()) { <b>show me multiple times, @Model.Whatever</b> } In a partial view, only include the block once no matter how many times the partial is repeated, but later render it specifically by name when-i-call-you: @using (Html.Delayed("when-i-call-you", isOnlyOne: "different unique name")) { <b>show me once by name</b> <span>@Model.First().Value</span> }

渲染“sections”

(即在父视图中显示延迟的部分)

@Html.RenderDelayed(); // writes unnamed sections (#1 and #2, excluding #3)
@Html.RenderDelayed("when-i-call-you", false); // writes the specified block, and ignore the `isOnlyOne` setting so we can dump it again
@Html.RenderDelayed("when-i-call-you"); // render the specified block by name
@Html.RenderDelayed("when-i-call-you"); // since it was "popped" in the last call, won't render anything due to `isOnlyOne` provided in `Html.Delayed`

CODE

public static class HtmlRenderExtensions {

    /// <summary>
    /// Delegate script/resource/etc injection until the end of the page
    /// <para>@via https://stackoverflow.com/a/14127332/1037948 and http://jadnb.wordpress.com/2011/02/16/rendering-scripts-from-partial-views-at-the-end-in-mvc/ </para>
    /// </summary>
    private class DelayedInjectionBlock : IDisposable {
        /// <summary>
        /// Unique internal storage key
        /// </summary>
        private const string CACHE_KEY = "DCCF8C78-2E36-4567-B0CF-FE052ACCE309"; // "DelayedInjectionBlocks";

        /// <summary>
        /// Internal storage identifier for remembering unique/isOnlyOne items
        /// </summary>
        private const string UNIQUE_IDENTIFIER_KEY = CACHE_KEY;

        /// <summary>
        /// What to use as internal storage identifier if no identifier provided (since we can't use null as key)
        /// </summary>
        private const string EMPTY_IDENTIFIER = "";

        /// <summary>
        /// Retrieve a context-aware list of cached output delegates from the given helper; uses the helper's context rather than singleton HttpContext.Current.Items
        /// </summary>
        /// <param name="helper">the helper from which we use the context</param>
        /// <param name="identifier">optional unique sub-identifier for a given injection block</param>
        /// <returns>list of delayed-execution callbacks to render internal content</returns>
        public static Queue<string> GetQueue(HtmlHelper helper, string identifier = null) {
            return _GetOrSet(helper, new Queue<string>(), identifier ?? EMPTY_IDENTIFIER);
        }

        /// <summary>
        /// Retrieve a context-aware list of cached output delegates from the given helper; uses the helper's context rather than singleton HttpContext.Current.Items
        /// </summary>
        /// <param name="helper">the helper from which we use the context</param>
        /// <param name="defaultValue">the default value to return if the cached item isn't found or isn't the expected type; can also be used to set with an arbitrary value</param>
        /// <param name="identifier">optional unique sub-identifier for a given injection block</param>
        /// <returns>list of delayed-execution callbacks to render internal content</returns>
        private static T _GetOrSet<T>(HtmlHelper helper, T defaultValue, string identifier = EMPTY_IDENTIFIER) where T : class {
            var storage = GetStorage(helper);

            // return the stored item, or set it if it does not exist
            return (T) (storage.ContainsKey(identifier) ? storage[identifier] : (storage[identifier] = defaultValue));
        }

        /// <summary>
        /// Get the storage, but if it doesn't exist or isn't the expected type, then create a new "bucket"
        /// </summary>
        /// <param name="helper"></param>
        /// <returns></returns>
        public static Dictionary<string, object> GetStorage(HtmlHelper helper) {
            var storage = helper.ViewContext.HttpContext.Items[CACHE_KEY] as Dictionary<string, object>;
            if (storage == null) helper.ViewContext.HttpContext.Items[CACHE_KEY] = (storage = new Dictionary<string, object>());
            return storage;
        }


        private readonly HtmlHelper helper;
        private readonly string identifier;
        private readonly string isOnlyOne;

        /// <summary>
        /// Create a new using block from the given helper (used for trapping appropriate context)
        /// </summary>
        /// <param name="helper">the helper from which we use the context</param>
        /// <param name="identifier">optional unique identifier to specify one or many injection blocks</param>
        /// <param name="isOnlyOne">extra identifier used to ensure that this item is only added once; if provided, content should only appear once in the page (i.e. only the first block called for this identifier is used)</param>
        public DelayedInjectionBlock(HtmlHelper helper, string identifier = null, string isOnlyOne = null) {
            this.helper = helper;

            // start a new writing context
            ((WebViewPage)this.helper.ViewDataContainer).OutputStack.Push(new StringWriter());

            this.identifier = identifier ?? EMPTY_IDENTIFIER;
            this.isOnlyOne = isOnlyOne;
        }

        /// <summary>
        /// Append the internal content to the context's cached list of output delegates
        /// </summary>
        public void Dispose() {
            // render the internal content of the injection block helper
            // make sure to pop from the stack rather than just render from the Writer
            // so it will remove it from regular rendering
            var content = ((WebViewPage)this.helper.ViewDataContainer).OutputStack;
            var renderedContent = content.Count == 0 ? string.Empty : content.Pop().ToString();
            // if we only want one, remove the existing
            var queue = GetQueue(this.helper, this.identifier);

            // get the index of the existing item from the alternate storage
            var existingIdentifiers = _GetOrSet(this.helper, new Dictionary<string, int>(), UNIQUE_IDENTIFIER_KEY);

            // only save the result if this isn't meant to be unique, or
            // if it's supposed to be unique and we haven't encountered this identifier before
            if( null == this.isOnlyOne || !existingIdentifiers.ContainsKey(this.isOnlyOne) ) {
                // remove the new writing context we created for this block
                // and save the output to the queue for later
                queue.Enqueue(renderedContent);

                // only remember this if supposed to
                if(null != this.isOnlyOne) existingIdentifiers[this.isOnlyOne] = queue.Count; // save the index, so we could remove it directly (if we want to use the last instance of the block rather than the first)
            }
        }
    }


    /// <summary>
    /// <para>Start a delayed-execution block of output -- this will be rendered/printed on the next call to <see cref="RenderDelayed"/>.</para>
    /// <para>
    /// <example>
    /// Print once in "default block" (usually rendered at end via <code>@Html.RenderDelayed()</code>).  Code:
    /// <code>
    /// @using (Html.Delayed()) {
    ///     <b>show at later</b>
    ///     <span>@Model.Name</span>
    ///     etc
    /// }
    /// </code>
    /// </example>
    /// </para>
    /// <para>
    /// <example>
    /// Print once (i.e. if within a looped partial), using identified block via <code>@Html.RenderDelayed("one-time")</code>.  Code:
    /// <code>
    /// @using (Html.Delayed("one-time", isOnlyOne: "one-time")) {
    ///     <b>show me once</b>
    ///     <span>@Model.First().Value</span>
    /// }
    /// </code>
    /// </example>
    /// </para>
    /// </summary>
    /// <param name="helper">the helper from which we use the context</param>
    /// <param name="injectionBlockId">optional unique identifier to specify one or many injection blocks</param>
    /// <param name="isOnlyOne">extra identifier used to ensure that this item is only added once; if provided, content should only appear once in the page (i.e. only the first block called for this identifier is used)</param>
    /// <returns>using block to wrap delayed output</returns>
    public static IDisposable Delayed(this HtmlHelper helper, string injectionBlockId = null, string isOnlyOne = null) {
        return new DelayedInjectionBlock(helper, injectionBlockId, isOnlyOne);
    }

    /// <summary>
    /// Render all queued output blocks injected via <see cref="Delayed"/>.
    /// <para>
    /// <example>
    /// Print all delayed blocks using default identifier (i.e. not provided)
    /// <code>
    /// @using (Html.Delayed()) {
    ///     <b>show me later</b>
    ///     <span>@Model.Name</span>
    ///     etc
    /// }
    /// </code>
    /// -- then later --
    /// <code>
    /// @using (Html.Delayed()) {
    ///     <b>more for later</b>
    ///     etc
    /// }
    /// </code>
    /// -- then later --
    /// <code>
    /// @Html.RenderDelayed() // will print both delayed blocks
    /// </code>
    /// </example>
    /// </para>
    /// <para>
    /// <example>
    /// Allow multiple repetitions of rendered blocks, using same <code>@Html.Delayed()...</code> as before.  Code:
    /// <code>
    /// @Html.RenderDelayed(removeAfterRendering: false); /* will print */
    /// @Html.RenderDelayed() /* will print again because not removed before */
    /// </code>
    /// </example>
    /// </para>

    /// </summary>
    /// <param name="helper">the helper from which we use the context</param>
    /// <param name="injectionBlockId">optional unique identifier to specify one or many injection blocks</param>
    /// <param name="removeAfterRendering">only render this once</param>
    /// <returns>rendered output content</returns>
    public static MvcHtmlString RenderDelayed(this HtmlHelper helper, string injectionBlockId = null, bool removeAfterRendering = true) {
        var stack = DelayedInjectionBlock.GetQueue(helper, injectionBlockId);

        if( removeAfterRendering ) {
            var sb = new StringBuilder(
#if DEBUG
                string.Format("<!-- delayed-block: {0} -->", injectionBlockId)
#endif
                );
            // .count faster than .any
            while (stack.Count > 0) {
                sb.AppendLine(stack.Dequeue());
            }
            return MvcHtmlString.Create(sb.ToString());
        } 

        return MvcHtmlString.Create(
#if DEBUG
                string.Format("<!-- delayed-block: {0} -->", injectionBlockId) + 
#endif
            string.Join(Environment.NewLine, stack));
    }


}

我能想到的第一个解决方案是使用ViewBag来存储必须呈现的值。

我从来没有试过,如果这个工作从一个局部的观点,但它应该在我看来。

我今天遇到了这个问题。我将添加一个工作区,使用<脚本延迟>,因为我没有看到其他答案提到它。

//on a JS file somewhere (i.e partial-view-caller.js)
(() => <your partial view script>)();

//in your Partial View
<script src="~/partial-view-caller.js" defer></script>

//you can actually just straight call your partial view script living in an external file - I just prefer having an initialization method :)

上面的代码摘自我关于这个问题的一篇文章。

OP的目标是将内联脚本定义到他的Partial View中,我假设这个脚本仅特定于该Partial View,并将该块包含到他的脚本部分中。

我明白他想要局部视图是独立的。这个想法类似于使用Angular时的组件。

我的方法是将脚本原样保存在Partial View中。现在的问题是,当调用Partial View时,它可能会在所有其他脚本(通常被添加到布局页面的底部)之前执行脚本。在这种情况下,您只需让Partial View脚本等待其他脚本。有几种方法可以做到这一点。我之前用过的最简单的方法是在body上使用事件。

在我的布局中,我会在底部有这样的东西:

// global scripts
<script src="js/jquery.min.js"></script>
// view scripts
@RenderSection("scripts", false)
// then finally trigger partial view scripts
<script>
  (function(){
    document.querySelector('body').dispatchEvent(new Event('scriptsLoaded'));
  })();
</script>

然后在我的局部视图(在底部):

<script>
  (function(){
    document.querySelector('body').addEventListener('scriptsLoaded', function() {

      // .. do your thing here

    });
  })();
</script>

另一种解决方案是使用堆栈来推送所有脚本,并在最后调用每个脚本。其他解决方案,如前所述,是RequireJS/AMD模式,它也非常有效。

我用这个方法解决了类似的问题:

@section ***{
@RenderSection("****", required: false)
}

我想这是一种很好的注射方式。