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SearchClientScriptProxy.cs
#region License /* ************************************************************** * Author: Rick Strahl * © West Wind Technologies, 2008 - 2009 * http://www.west-wind.com/ * * Permission is hereby granted, free of charge, to any person * obtaining a copy of this software and associated documentation * files (the "Software"), to deal in the Software without * restriction, including without limitation the rights to use, * copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the * Software is furnished to do so, subject to the following * conditions: * * The above copyright notice and this permission notice shall be * included in all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR * OTHER DEALINGS IN THE SOFTWARE. ************************************************************** */ #endregion // undefine this constant to remove the code that allows for // optional script compression with the ScriptingModule // when MS Ajax is not available. #define IncludeScriptCompressionModuleSupport using System; using System.Web; using System.Web.UI; using System.Reflection; using System.Text; using System.IO; using System.Linq; using System.Collections.Generic; using Westwind.Utilities; using System.Collections; namespace Westwind.Web { /// <summary> /// This is a proxy object for the Page.ClientScript and MS Ajax ScriptManager /// object that can operate when MS Ajax when present otherwise falling back to /// Page.ClientScript. Because MS Ajax may not be available accessing the /// methods directly is not possible and we are required to indirectly /// reference client script methods through this class. /// /// This class should be invoked at the Control's start up and be used to /// replace all calls Page.ClientScript. Scriptmanager calls are made through /// Reflection indirectly so there's no dependency on the script manager. /// /// This class also provides a few additional page injection helpers like the /// abillity to load scripts in the page header (rather than in the body) and /// to use script compression using wwScriptCompressionModule without using MS /// Ajax. /// </summary> public class ClientScriptProxy { private const string STR_CONTEXTID = "__ClientScriptProxy"; private const string STR_SCRIPTITEM_IDENTITIFIER = "script_"; private const string STR_ScriptResourceIndex = "__ScriptResourceIndex"; private static Type scriptManagerType = null; // Register proxied methods of ScriptManager private static MethodInfo RegisterClientScriptBlockMethod; private static MethodInfo RegisterStartupScriptMethod; private static MethodInfo RegisterClientScriptIncludeMethod; private static MethodInfo RegisterHiddenFieldMethod; private static MethodInfo GetCurrentMethod; //private static MethodInfo RegisterPostBackControlMethod; //private static MethodInfo GetWebResourceUrlMethod; /// <summary> /// Determines the default script rendering mode that is uses if no script rendering mode /// is explicitly provided on the control. /// /// This setting is global and should be set only once in Appplication_Start or /// a static constructor. /// </summary> public static ScriptRenderModes DefaultScriptRenderMode = ScriptRenderModes.Script; /// <summary> /// List of ResourceToFile map items that map script resources loaded via Resources to just /// script filenames. These filenames can be compared against real file based scripts /// (when loaded through ScriptContainer) to be detected and only be loaded once. /// /// Note this is a List<> because there may be multiple supported values for a single /// resource (ie. not unique). /// </summary> public static List<ScriptResourceAlias> ScriptResourceAliases = new List<ScriptResourceAlias>() { new ScriptResourceAlias() { Alias = "jquery", Resource = ControlResources.JQUERY_SCRIPT_RESOURCE, FileId="jquery.js"}, new ScriptResourceAlias() { Alias = "ww.jquery", Resource = ControlResources.WWJQUERY_SCRIPT_RESOURCE, FileId = "ww.jquery.js" }, new ScriptResourceAlias() { Alias = "jqueryui", Resource = null, FileId = "jquery-ui.js" }, new ScriptResourceAlias() { Alias = "jquery.js", Resource = ControlResources.JQUERY_SCRIPT_RESOURCE, FileId="jquery.js"}, new ScriptResourceAlias() { Alias = "ww.jquery.js", Resource = ControlResources.WWJQUERY_SCRIPT_RESOURCE, FileId = "ww.jquery.js" }, new ScriptResourceAlias() { Alias = "jquery-ui.js", Resource = null, FileId = "jquery-ui.js" }, // The following are the min.js versions - just an alias so we can find them new ScriptResourceAlias() { Alias = "NONE", Resource = ControlResources.JQUERY_SCRIPT_RESOURCE, FileId = "jquery.min.js" }, new ScriptResourceAlias() { Alias = "NONE", Resource = ControlResources.WWJQUERY_SCRIPT_RESOURCE, FileId = "ww.jquery.min.js" } }; /// <summary> /// Internal global static that gets set when IsMsAjax() is /// called. The result is cached once per application so /// we don't have keep making reflection calls for each access /// </summary> private static bool _IsMsAjax = false; /// <summary> /// Flag that determines whether check was previously done /// </summary> private static bool _CheckedForMsAjax = false; /// <summary> /// Cached value to see whether the script manager is /// on the page. This value caches here once per page. /// </summary> private bool _IsScriptManagerOnPage = false; private bool _CheckedForScriptManager = false; private List<string> _loadedScripts = new List<string>(); internal bool IsTransferred = false; /// <summary> /// Current instance of this class which should always be used to /// access this object. There are no public constructors to /// ensure the reference is used as a Singleton to further /// ensure that all scripts are written to the same clientscript /// manager. /// </summary> public static ClientScriptProxy Current { get { if (HttpContext.Current == null) return new ClientScriptProxy(); ClientScriptProxy proxy = null; if (HttpContext.Current.Items.Contains(STR_CONTEXTID)) proxy = HttpContext.Current.Items[STR_CONTEXTID] as ClientScriptProxy; else { proxy = new ClientScriptProxy(); HttpContext.Current.Items[STR_CONTEXTID] = proxy; } if (!proxy.IsTransferred && HttpContext.Current.Handler != HttpContext.Current.CurrentHandler) { proxy.ClearContextItemsOnTransfer(); HttpContext.Current.Items[STR_CONTEXTID] = proxy; proxy.IsTransferred = true; } return proxy; } } /// <summary> /// No public constructor - use ClientScriptProxy.Current to /// get an instance to ensure you once have one instance per /// page active. /// </summary> protected ClientScriptProxy() { } /// <summary> /// Clears all the request specific context items which are script references /// and the script placement index. /// </summary> public void ClearContextItemsOnTransfer() { if (HttpContext.Current != null) { // Check for Server.Transfer/Execute calls - we need to clear out Context.Items if (HttpContext.Current.CurrentHandler != HttpContext.Current.Handler) { List<string> Keys = HttpContext.Current.Items.Keys.Cast<string>().Where(s => s.StartsWith(STR_SCRIPTITEM_IDENTITIFIER) || s == STR_ScriptResourceIndex).ToList(); foreach (string key in Keys) { HttpContext.Current.Items.Remove(key); } } } } #region ScriptManager Detection routines /// <summary> /// Checks to see if MS Ajax is registered with the current /// Web application. /// /// Note: Method is static so it can be directly accessed from /// anywhere. If you use the IsMsAjax property to check the /// value this method fires only once per application. /// </summary> /// <returns></returns> public static bool IsMsAjax() { if (_CheckedForMsAjax) return _IsMsAjax; // Easiest but we don't want to hardcode the version here // scriptManagerType = Type.GetType("System.Web.UI.ScriptManager, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35", false); // To be safe and compliant we need to look through all loaded assemblies Assembly ScriptAssembly = null; // Assembly.LoadWithPartialName("System.Web.Extensions"); foreach (Assembly ass in AppDomain.CurrentDomain.GetAssemblies()) { string fn = ass.FullName; if (fn.StartsWith("System.Web.Extensions")) { ScriptAssembly = ass; break; } } if (ScriptAssembly == null) return false; scriptManagerType = ScriptAssembly.GetType("System.Web.UI.ScriptManager"); if (scriptManagerType == null) { _IsMsAjax = false; _CheckedForMsAjax = true; return false; } // Method to check for current instance on a page - cache // since we might call this frequently GetCurrentMethod = scriptManagerType.GetMethod("GetCurrent"); _IsMsAjax = true; _CheckedForMsAjax = true; return true; } /// <summary> /// Checks to see if a script manager is on the page /// </summary> /// <param name="control"></param> /// <returns></returns> public bool IsScriptManagerOnPage(Page page) { // Check is done only once per page if (_CheckedForScriptManager) return _IsScriptManagerOnPage; // Must check whether MS Ajax is available // at all first. Method sets up scriptManager // and GetCurrentMethod on success. if (!IsMsAjax()) { _CheckedForScriptManager = true; _IsScriptManagerOnPage = false; return false; } // Now check and see if we can get a ref to the script manager object sm = GetCurrentMethod.Invoke(null, new object[1] { page }); if (sm == null) _IsScriptManagerOnPage = false; else _IsScriptManagerOnPage = true; _CheckedForScriptManager = true; return _IsScriptManagerOnPage; } #endregion /// <summary> /// High level helper function that is used to load script resources for various AJAX controls /// Loads a script resource based on the following scriptLocation values: /// /// * WebResource /// Loads the Web Resource specified out of ControlResources. Specify the resource /// that applied in the resourceName parameter /// /// * Url/RelativeUrl /// loads the url with ResolveUrl applied /// /// * empty string (no value) /// No action is taken and nothing is embedded into the page. Use this if you manually /// want to load resources /// </summary> /// <param name="control">The control instance for which the resource is to be loaded</param> /// <param name="scriptLocation">WebResource, a virtual path or a full Url. Empty to not embed any script refs (ie. user loads script herself)</param> /// <param name="resourceName">The name of the resource when WebResource is used for scriptLocation null otherwise</param> /// <param name="topOfHeader">Determines if scripts are loaded into the header whether they load at the top or bottom</param> public void LoadControlScript(Control control, string scriptLocation, string resourceName, ScriptRenderModes renderMode) { // Specified nothing to do if (string.IsNullOrEmpty(scriptLocation)) return; if (scriptLocation == "WebResource") { RegisterClientScriptResource(control, control.GetType(), resourceName,renderMode); return; } RegisterClientScriptInclude(control, control.GetType(), control.ResolveUrl(scriptLocation), renderMode); } public void LoadControlScript(Control control, string scriptLocation, string resourceName) { LoadControlScript(control, scriptLocation, resourceName, ScriptRenderModes.Inherit); } public void LoadControlScript(Control control, string scriptLocation) { LoadControlScript(control, scriptLocation, null, ScriptRenderModes.Inherit); } /// <summary> /// Returns a WebResource or ScriptResource URL for script resources that are to be /// embedded as script includes. /// </summary> /// <param name="control">Any control</param> /// <param name="type">A type in assembly where resources are located</param> /// <param name="resourceName">Name of the resource to load</param> /// <param name="renderMode">Determines where in the document the link is rendered</param> public void RegisterClientScriptResource(Control control, Type type, string resourceName, ScriptRenderModes renderMode) { string resourceUrl = GetClientScriptResourceUrl(control, type, resourceName); RegisterClientScriptInclude(control, type, resourceUrl, renderMode); } /// <summary> /// Registers a script include tag into the page for an external script url. /// /// This version embeds only in the body of the HTML document - ie. underneath the form tag /// </summary> /// <param name="control"></param> /// <param name="type"></param> /// <param name="key"></param> /// <param name="url"></param> public void RegisterClientScriptInclude(Control control, Type type, string key, string url) { url = WebUtils.ResolveUrl(url); if (IsScriptManagerOnPage(control.Page)) { if (RegisterClientScriptIncludeMethod == null) RegisterClientScriptIncludeMethod = scriptManagerType.GetMethod("RegisterClientScriptInclude", new Type[4] { typeof(Control), typeof(Type), typeof(string), typeof(string) }); RegisterClientScriptIncludeMethod.Invoke(null, new object[4] { control, type, key, url }); } else control.Page.ClientScript.RegisterClientScriptInclude(type, key, url); } /// <summary> /// Registers a client script reference into the page with the option to specify /// the script location in the page /// </summary> /// <param name="control">Any control instance - typically page</param> /// <param name="type">Type that acts as qualifier (uniqueness)</param> /// <param name="url">the Url to the script resource</param> /// <param name="ScriptRenderModes">Determines where the script is rendered</param> public void RegisterClientScriptInclude(Control control, Type type, string url, ScriptRenderModes renderMode) { if (string.IsNullOrEmpty(url)) return; if (renderMode == ScriptRenderModes.Inherit) renderMode = DefaultScriptRenderMode; // Extract just the script filename string fileId = null; // Check resource IDs and try to match to mapped file resources // Used to allow scripts not to be loaded more than once whether // embedded manually (script tag) or via resources with ClientScriptProxy if (url.Contains(".axd?r=")) { string res = HttpUtility.UrlDecode( StringUtils.ExtractString(url, "?r=", "&", false, true) ); foreach (ScriptResourceAlias item in ScriptResourceAliases) { if (item.Resource == res) { fileId = item.Alias + ".js"; break; } } if (fileId == null) fileId = url.ToLower(); } else fileId = Path.GetFileName(url).ToLower(); // Normalize minimized files and plain .js file as the same fileid if (fileId.EndsWith("min.js")) fileId = fileId.Replace(".min.js", ".js"); // No dupes - ref script include only once if (HttpContext.Current.Items.Contains( STR_SCRIPTITEM_IDENTITIFIER + fileId ) ) return; HttpContext.Current.Items.Add(STR_SCRIPTITEM_IDENTITIFIER + fileId, string.Empty); // just use script manager or ClientScriptManager if (control.Page.Header == null || renderMode == ScriptRenderModes.Script || renderMode == ScriptRenderModes.Inline) { RegisterClientScriptInclude(control, type,url, url); return; } // Retrieve script index in header int? index = HttpContext.Current.Items[STR_ScriptResourceIndex] as int?; if (index == null) index = 0; StringBuilder sb = new StringBuilder(256); url = WebUtils.ResolveUrl(url); // Embed in header sb.AppendLine("\r\n<script src=\"" + url + "\" type=\"text/javascript\"></script>"); if (renderMode == ScriptRenderModes.HeaderTop) { control.Page.Header.Controls.AddAt(index.Value, new LiteralControl(sb.ToString())); index++; } else if (renderMode == ScriptRenderModes.Header) control.Page.Header.Controls.Add(new LiteralControl(sb.ToString())); else if (renderMode == ScriptRenderModes.BottomOfPage) control.Page.Controls.AddAt(control.Page.Controls.Count-1, new LiteralControl(sb.ToString())); HttpContext.Current.Items[STR_ScriptResourceIndex] = index; } /// <summary> /// Registers a CSS Web Resource in the page /// </summary> /// <param name="control"></param> /// <param name="type"></param> /// <param name="resourceName"></param> public void RegisterCssResource(Control control, Type type, string resourceName) { // Otherwise just embed a css reference into the page using standard page methods string resourceUrl = GetClientScriptResourceUrl(control,type, resourceName); RegisterCssLink(control, type, resourceName, resourceUrl); } /// <summary> /// Keep track of keys that were written /// </summary> private HashSet<string> cssLinks = new HashSet<string>(); /// <summary> /// Registers a CSS stylesheet in the page header and if that's not accessible inside of the form tag. /// </summary> /// <param name="control"></param> /// <param name="type"></param> /// <param name="key"></param> /// <param name="url"></param> public void RegisterCssLink(Control control, Type type, string key, string url) { if (string.IsNullOrEmpty(url)) return; string lowerUrl = url.ToLower(); if (cssLinks.Contains(lowerUrl)) return; // already added Control container = control.Page.Header; if (container == null) container = control.Page.Form; if (container == null) throw new InvalidOperationException("There's no header or form to add CSS to Register Resource CSS on the page."); string output = "<link href=\"" + control.ResolveUrl(url) + "\" rel=\"stylesheet\" type=\"text/css\" >\r\n"; container.Controls.Add(new LiteralControl(output)); cssLinks.Add(lowerUrl); } /// <summary> /// Registers a client script block in the page. /// </summary> /// <param name="control"></param> /// <param name="type"></param> /// <param name="key"></param> /// <param name="script"></param> /// <param name="addScriptTags"></param> public void RegisterClientScriptBlock(Control control, Type type, string key, string script, bool addScriptTags) { if (IsMsAjax()) { if (RegisterClientScriptBlockMethod == null) RegisterClientScriptBlockMethod = scriptManagerType.GetMethod("RegisterClientScriptBlock", new Type[5] { typeof(Control), typeof(Type), typeof(string), typeof(string), typeof(bool) }); RegisterClientScriptBlockMethod.Invoke(null, new object[5] { control, type, key, script, addScriptTags }); } else control.Page.ClientScript.RegisterClientScriptBlock(type, key, script, addScriptTags); } /// <summary> /// Renders client script block with the option of rendering the script block in /// the Html header /// /// For this to work Header must be defined as runat="server" /// </summary> /// <param name="control">any control that instance typically page</param> /// <param name="type">Type that identifies this rendering</param> /// <param name="key">unique script block id</param> /// <param name="script">The script code to render</param> /// <param name="addScriptTags">Ignored for header rendering used for all other insertions</param> /// <param name="renderMode">Where the block is rendered</param> public void RegisterClientScriptBlock(Control control, Type type, string key, string script, bool addScriptTags, ScriptRenderModes renderMode) { if (renderMode == ScriptRenderModes.Inherit) renderMode = DefaultScriptRenderMode; if (control.Page.Header == null || renderMode != ScriptRenderModes.HeaderTop && renderMode != ScriptRenderModes.Header && renderMode != ScriptRenderModes.BottomOfPage) { RegisterClientScriptBlock(control, type, key, script, addScriptTags); return; } // No dupes - ref script include only once const string identifier = "scriptblock_"; if (HttpContext.Current.Items.Contains(identifier + key)) return; HttpContext.Current.Items.Add(identifier + key, string.Empty); StringBuilder sb = new StringBuilder(); // Embed in header sb.AppendLine("\r\n<script type=\"text/javascript\">"); sb.AppendLine(script); sb.AppendLine("</script>"); int? index = HttpContext.Current.Items[STR_ScriptResourceIndex] as int?; if (index == null) index = 0; if (renderMode == ScriptRenderModes.HeaderTop) { control.Page.Header.Controls.AddAt(index.Value, new LiteralControl(sb.ToString())); index++; } else if (renderMode == ScriptRenderModes.Header) control.Page.Header.Controls.Add(new LiteralControl(sb.ToString())); else if (renderMode == ScriptRenderModes.BottomOfPage) control.Page.Controls.AddAt(control.Page.Controls.Count - 1, new LiteralControl(sb.ToString())); HttpContext.Current.Items[STR_ScriptResourceIndex] = index; } /// <summary> /// Registers a startup code snippet that gets placed at the bottom of the page /// </summary> /// <param name="control"></param> /// <param name="type"></param> /// <param name="key"></param> /// <param name="script"></param> /// <param name="addStartupTags"></param> public void RegisterStartupScript(Control control, Type type, string key, string script, bool addStartupTags) { if (IsMsAjax()) { if (RegisterStartupScriptMethod == null) RegisterStartupScriptMethod = scriptManagerType.GetMethod("RegisterStartupScript", new Type[5] { typeof(Control), typeof(Type), typeof(string), typeof(string), typeof(bool) }); RegisterStartupScriptMethod.Invoke(null, new object[5] { control, type, key, script, addStartupTags }); } else control.Page.ClientScript.RegisterStartupScript(type, key, script, addStartupTags); } /// <summary> /// Returns a WebResource URL for non script resources /// </summary> /// <param name="control"></param> /// <param name="type"></param> /// <param name="resourceName"></param> /// <returns></returns> public string GetWebResourceUrl(Control control, Type type, string resourceName) { return control.Page.ClientScript.GetWebResourceUrl(type, resourceName); } /// <summary> /// Works like GetWebResourceUrl but can be used with javascript resources /// to allow using of resource compression (if the module is loaded). /// </summary> /// <param name="control"></param> /// <param name="type"></param> /// <param name="resourceName"></param> /// <returns></returns> public string GetClientScriptResourceUrl(Control control, Type type, string resourceName) { #if IncludeScriptCompressionModuleSupport // If wwScriptCompression Module through Web.config is loaded use it to compress // script resources by using wcSC.axd Url the module intercepts if (ScriptCompressionModule.ScriptCompressionModuleActive) { string url = "~/wwSC.axd?r=" + HttpUtility.UrlEncode(resourceName); if (type.Assembly != GetType().Assembly) url += "&t=" + HttpUtility.UrlEncode(type.FullName); return WebUtils.ResolveUrl(url); } #endif return control.Page.ClientScript.GetWebResourceUrl(type, resourceName); } /// <summary> /// Injects a hidden field into the page /// </summary> /// <param name="control"></param> /// <param name="hiddenFieldName"></param> /// <param name="hiddenFieldInitialValue"></param> public void RegisterHiddenField(Control control, string hiddenFieldName, string hiddenFieldInitialValue) { if (IsMsAjax()) { if (RegisterHiddenFieldMethod == null) RegisterHiddenFieldMethod = scriptManagerType.GetMethod("RegisterHiddenField", new Type[3] { typeof(Control), typeof(string), typeof(string) }); RegisterHiddenFieldMethod.Invoke(null, new object[3] { control, hiddenFieldName, hiddenFieldInitialValue }); } else control.Page.ClientScript.RegisterHiddenField(hiddenFieldName, hiddenFieldInitialValue); } } /// <summary> /// Determines how scripts are included into the page /// </summary> public enum ScriptRenderModes { /// <summary> /// Inherits the setting from the control or from the ClientScript.DefaultScriptRenderMode /// </summary> Inherit, /// Renders the script include at the location of the control /// </summary> Inline, /// <summary> /// Renders the script include into the bottom of the header of the page /// </summary> Header, /// <summary> /// Renders the script include into the top of the header of the page /// </summary> HeaderTop, /// <summary> /// Uses ClientScript or ScriptManager to embed the script include to /// provide standard ASP.NET style rendering in the HTML body. /// </summary> Script, /// <summary> /// Renders script at the bottom of the page before the last Page.Controls /// literal control. Note this may result in unexpected behavior /// if /body and /html are not the last thing in the markup page. /// </summary> BottomOfPage } public struct ScriptResourceAlias { /// <summary> /// An alias/shortcut resource name /// </summary> public string Alias; /// <summary> /// The name of the script file that this resource maps to. Should be just /// the filename (ie. jquery.js or ww.jquery.js) as well as min.js versions /// if those files are loaded as well /// </summary> public string FileId; /// <summary> /// The full resource name to the resourceToFileItem /// </summary> public string Resource; /// <summary> /// Any type in the assembly that contains the script resource /// If null looks in the current executing assembly. /// </summary> public Type ControlType; } }
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