Tôi đã có một vấn đề tương tự, và cuối cùng đã áp dụng câu trả lời tuyệt vời của Kalman với đoạn mã dưới đây (không hoàn toàn gọn gàng, nhưng có thể mở rộng hơn nhiều):
namespace MvcHtmlHelpers
{
//http://stackoverflow.com/questions/5110028/add-css-or-js-files-to-layout-head-from-views-or-partial-views#5148224
public static partial class HtmlExtensions
{
public static AssetsHelper Assets(this HtmlHelper htmlHelper)
{
return AssetsHelper.GetInstance(htmlHelper);
}
}
public enum BrowserType { Ie6=1,Ie7=2,Ie8=4,IeLegacy=7,W3cCompliant=8,All=15}
public class AssetsHelper
{
public static AssetsHelper GetInstance(HtmlHelper htmlHelper)
{
var instanceKey = "AssetsHelperInstance";
var context = htmlHelper.ViewContext.HttpContext;
if (context == null) {return null;}
var assetsHelper = (AssetsHelper)context.Items[instanceKey];
if (assetsHelper == null){context.Items.Add(instanceKey, assetsHelper = new AssetsHelper(htmlHelper));}
return assetsHelper;
}
private readonly List<string> _styleRefs = new List<string>();
public AssetsHelper AddStyle(string stylesheet)
{
_styleRefs.Add(stylesheet);
return this;
}
private readonly List<string> _scriptRefs = new List<string>();
public AssetsHelper AddScript(string scriptfile)
{
_scriptRefs.Add(scriptfile);
return this;
}
public IHtmlString RenderStyles()
{
ItemRegistrar styles = new ItemRegistrar(ItemRegistrarFormatters.StyleFormat,_urlHelper);
styles.Add(Libraries.UsedStyles());
styles.Add(_styleRefs);
return styles.Render();
}
public IHtmlString RenderScripts()
{
ItemRegistrar scripts = new ItemRegistrar(ItemRegistrarFormatters.ScriptFormat, _urlHelper);
scripts.Add(Libraries.UsedScripts());
scripts.Add(_scriptRefs);
return scripts.Render();
}
public LibraryRegistrar Libraries { get; private set; }
private UrlHelper _urlHelper;
public AssetsHelper(HtmlHelper htmlHelper)
{
_urlHelper = new UrlHelper(htmlHelper.ViewContext.RequestContext);
Libraries = new LibraryRegistrar();
}
}
public class LibraryRegistrar
{
public class Component
{
internal class HtmlReference
{
internal string Url { get; set; }
internal BrowserType ServeTo { get; set; }
}
internal List<HtmlReference> Styles { get; private set; }
internal List<HtmlReference> Scripts { get; private set; }
internal List<string> RequiredLibraries { get; private set; }
public Component()
{
Styles = new List<HtmlReference>();
Scripts = new List<HtmlReference>();
RequiredLibraries = new List<string>();
}
public Component Requires(params string[] libraryNames)
{
foreach (var lib in libraryNames)
{
if (!RequiredLibraries.Contains(lib))
{ RequiredLibraries.Add(lib); }
}
return this;
}
public Component AddStyle(string url, BrowserType serveTo = BrowserType.All)
{
Styles.Add(new HtmlReference { Url = url, ServeTo=serveTo });
return this;
}
public Component AddScript(string url, BrowserType serveTo = BrowserType.All)
{
Scripts.Add(new HtmlReference { Url = url, ServeTo = serveTo });
return this;
}
}
private readonly Dictionary<string, Component> _allLibraries = new Dictionary<string, Component>();
private List<string> _usedLibraries = new List<string>();
internal IEnumerable<string> UsedScripts()
{
SetOrder();
var returnVal = new List<string>();
foreach (var key in _usedLibraries)
{
returnVal.AddRange(from s in _allLibraries[key].Scripts
where IncludesCurrentBrowser(s.ServeTo)
select s.Url);
}
return returnVal;
}
internal IEnumerable<string> UsedStyles()
{
SetOrder();
var returnVal = new List<string>();
foreach (var key in _usedLibraries)
{
returnVal.AddRange(from s in _allLibraries[key].Styles
where IncludesCurrentBrowser(s.ServeTo)
select s.Url);
}
return returnVal;
}
public void Uses(params string[] libraryNames)
{
foreach (var name in libraryNames)
{
if (!_usedLibraries.Contains(name)){_usedLibraries.Add(name);}
}
}
public bool IsUsing(string libraryName)
{
SetOrder();
return _usedLibraries.Contains(libraryName);
}
private List<string> WalkLibraryTree(List<string> libraryNames)
{
var returnList = new List<string>(libraryNames);
int counter = 0;
foreach (string libraryName in libraryNames)
{
WalkLibraryTree(libraryName, ref returnList, ref counter);
}
return returnList;
}
private void WalkLibraryTree(string libraryName, ref List<string> libBuild, ref int counter)
{
if (counter++ > 1000) { throw new System.Exception("Dependancy library appears to be in infinate loop - please check for circular reference"); }
Component library;
if (!_allLibraries.TryGetValue(libraryName, out library))
{ throw new KeyNotFoundException("Cannot find a definition for the required style/script library named: " + libraryName); }
foreach (var childLibraryName in library.RequiredLibraries)
{
int childIndex = libBuild.IndexOf(childLibraryName);
if (childIndex!=-1)
{
//child already exists, so move parent to position before child if it isn't before already
int parentIndex = libBuild.LastIndexOf(libraryName);
if (parentIndex>childIndex)
{
libBuild.RemoveAt(parentIndex);
libBuild.Insert(childIndex, libraryName);
}
}
else
{
libBuild.Add(childLibraryName);
WalkLibraryTree(childLibraryName, ref libBuild, ref counter);
}
}
return;
}
private bool _dependenciesExpanded;
private void SetOrder()
{
if (_dependenciesExpanded){return;}
_usedLibraries = WalkLibraryTree(_usedLibraries);
_usedLibraries.Reverse();
_dependenciesExpanded = true;
}
public Component this[string index]
{
get
{
if (_allLibraries.ContainsKey(index))
{ return _allLibraries[index]; }
var newComponent = new Component();
_allLibraries.Add(index, newComponent);
return newComponent;
}
}
private BrowserType _requestingBrowser;
private BrowserType RequestingBrowser
{
get
{
if (_requestingBrowser == 0)
{
var browser = HttpContext.Current.Request.Browser.Type;
if (browser.Length > 2 && browser.Substring(0, 2) == "IE")
{
switch (browser[2])
{
case '6':
_requestingBrowser = BrowserType.Ie6;
break;
case '7':
_requestingBrowser = BrowserType.Ie7;
break;
case '8':
_requestingBrowser = BrowserType.Ie8;
break;
default:
_requestingBrowser = BrowserType.W3cCompliant;
break;
}
}
else
{
_requestingBrowser = BrowserType.W3cCompliant;
}
}
return _requestingBrowser;
}
}
private bool IncludesCurrentBrowser(BrowserType browserType)
{
if (browserType == BrowserType.All) { return true; }
return (browserType & RequestingBrowser) != 0;
}
}
public class ItemRegistrar
{
private readonly string _format;
private readonly List<string> _items;
private readonly UrlHelper _urlHelper;
public ItemRegistrar(string format, UrlHelper urlHelper)
{
_format = format;
_items = new List<string>();
_urlHelper = urlHelper;
}
internal void Add(IEnumerable<string> urls)
{
foreach (string url in urls)
{
Add(url);
}
}
public ItemRegistrar Add(string url)
{
url = _urlHelper.Content(url);
if (!_items.Contains(url))
{ _items.Add( url); }
return this;
}
public IHtmlString Render()
{
var sb = new StringBuilder();
foreach (var item in _items)
{
var fmt = string.Format(_format, item);
sb.AppendLine(fmt);
}
return new HtmlString(sb.ToString());
}
}
public class ItemRegistrarFormatters
{
public const string StyleFormat = "<link href=\"{0}\" rel=\"stylesheet\" type=\"text/css\" />";
public const string ScriptFormat = "<script src=\"{0}\" type=\"text/javascript\"></script>";
}
}
Dự án chứa một phương thức AssignAllResource tĩnh:
assets.Libraries["jQuery"]
.AddScript("~/Scripts/jquery-1.10.0.min.js", BrowserType.IeLegacy)
.AddScript("~/Scripts//jquery-2.0.1.min.js",BrowserType.W3cCompliant);
/* NOT HOSTED YET - CHECK SOON
.AddScript("//ajax.googleapis.com/ajax/libs/jquery/2.0.1/jquery.min.js",BrowserType.W3cCompliant);
*/
assets.Libraries["jQueryUI"].Requires("jQuery")
.AddScript("//ajax.googleapis.com/ajax/libs/jqueryui/1.9.2/jquery-ui.min.js",BrowserType.Ie6)
.AddStyle("//ajax.aspnetcdn.com/ajax/jquery.ui/1.9.2/themes/eggplant/jquery-ui.css",BrowserType.Ie6)
.AddScript("//ajax.googleapis.com/ajax/libs/jqueryui/1.10.3/jquery-ui.min.js", ~BrowserType.Ie6)
.AddStyle("//ajax.aspnetcdn.com/ajax/jquery.ui/1.10.3/themes/eggplant/jquery-ui.css", ~BrowserType.Ie6);
assets.Libraries["TimePicker"].Requires("jQueryUI")
.AddScript("~/Scripts/jquery-ui-sliderAccess.min.js")
.AddScript("~/Scripts/jquery-ui-timepicker-addon-1.3.min.js")
.AddStyle("~/Content/jQueryUI/jquery-ui-timepicker-addon.css");
assets.Libraries["Validation"].Requires("jQuery")
.AddScript("//ajax.aspnetcdn.com/ajax/jquery.validate/1.11.1/jquery.validate.min.js")
.AddScript("~/Scripts/jquery.validate.unobtrusive.min.js")
.AddScript("~/Scripts/mvcfoolproof.unobtrusive.min.js")
.AddScript("~/Scripts/CustomClientValidation-1.0.0.min.js");
assets.Libraries["MyUtilityScripts"].Requires("jQuery")
.AddScript("~/Scripts/GeneralOnLoad-1.0.0.min.js");
assets.Libraries["FormTools"].Requires("Validation", "MyUtilityScripts");
assets.Libraries["AjaxFormTools"].Requires("FormTools", "jQueryUI")
.AddScript("~/Scripts/jquery.unobtrusive-ajax.min.js");
assets.Libraries["DataTables"].Requires("MyUtilityScripts")
.AddScript("//ajax.aspnetcdn.com/ajax/jquery.dataTables/1.9.4/jquery.dataTables.min.js")
.AddStyle("//ajax.aspnetcdn.com/ajax/jquery.dataTables/1.9.4/css/jquery.dataTables.css")
.AddStyle("//ajax.aspnetcdn.com/ajax/jquery.dataTables/1.9.4/css/jquery.dataTables_themeroller.css");
assets.Libraries["MvcDataTables"].Requires("DataTables", "jQueryUI")
.AddScript("~/Scripts/jquery.dataTables.columnFilter.min.js");
assets.Libraries["DummyData"].Requires("MyUtilityScripts")
.AddScript("~/Scripts/DummyData.js")
.AddStyle("~/Content/DummyData.css");
trong trang _layout
@{
var assets = Html.Assets();
CurrentResources.AssignAllResources(assets);
Html.Assets().RenderStyles()
}
</head>
...
@Html.Assets().RenderScripts()
</body>
và trong một phần (s) và lượt xem
Html.Assets().Libraries.Uses("DataTables");
Html.Assets().AddScript("~/Scripts/emailGridUtilities.js");