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  • calling java script function then C# function after clicking ASP.NET button

    - by Eyla
    I have this serious: I have ASP.NET page, This page contents Update panel with ASP.NET control. I have Java script function to do validation so when I click the button I will use onclientclick to call the java function to do the validation and after this one done should call then event click button function from code behind. I tried vew methods but they did not work for me. here is sample of my code that after I click the button onclientclick will call the java script function for validation and if the validation is OK should call onclick event. .................... java script function ........................ <script type="text/javascript" > function add(){ if (tag == trye) { document.getElementById('<%=btnInfor.ClientID%>').click(); alert("DataAdded") } else { alert("Requiered Field Missing.") return false; } } </script> ..................... ASP.NET button ................... <asp:Button ID="btnInfor" runat="server" Text="Add Information" Style="position: absolute; top: 1659px; left: 433px;" onclientclick="JavaScript: return myAdd()" /> .................... code behind in C# ...................... protected void btnInfor_Click(object sender, EventArgs e) { \\mycode }

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  • How to implement parent-child windows and pass values from child to parent?

    - by Andrew
    I am working on an ASP.NET MVC 2 application. In one of my data entry forms, I have an "employer" field which has a "search" link next to it. When a user clicks on this link, another window is opened with a search form. The user uses the search form to search for the correct employer. A list of employers is shown to the user. Currently, the user has to then copy and paste the correct employer from the child window into the original window. I want to implement it so that each employer search result in the child window is a hyperlink. The user would then click on the correct employer and then the correct employer value would be populated in the original parent window employer field. How would I go about implementing this in ASP.NET MVC 2?

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  • ASP can't connect to SQL Server database

    - by birdus
    I'm trying to get a classic ASP application to connect to a local SQL Server 2008 database. The app and database were built by someone else. I'm just trying to get them installed and running on my machine (Windows 7). I'm getting the following error when when the ASP app tries to connect to the database: Could not connect to database: Error Number: -2147467259 Error Message: [ConnectionOpen (Connect()).] does not exist or access denied. I don't see any messages in the Windows Event Viewer. I'm looking at: Event Viewer-Windows Logs-Application. It's a fresh database install using a simple restore. The SQL Server install uses the default instance. SQL Server and Windows authentication are both allowed. I left the existing connection string (in the ASP code) in tact and just tried adding that to my SQL Server installation. Here's the connection string: strConn = "PROVIDER=SQLOLEDB;SERVER=localhost;UID=TheUser;PWD=ThePassword;DATABASE=TheDatabase;" To add that user to SQL Server, I went to Security/Logins in SSMS and added the user and the password. I selected the database in question as the Default database. I thought that might do the trick, but it didn't. Then, I went into TheDatabase, then went into Security there. I added a new user there, referencing the new user I had already added in server Security. Under Owned Schemas, I clicked db_owner and under Role Members I checked db_accessadmin and db_owner. None of this gave the ASP application access to the database. The sid values match in sys.database_principals and sys.server_principals for the login in question. I am able to login to SSMS using this login. The app needs to execute selects against the database like this: oConn.Execute('select * from someTable') I'm not a DBA and am sort of grasping at straws here. How do I get this thing connected? Thanks, Jay

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  • dynamic LinkButton OnClick event not working on ASP.Net

    - by user1004472
    I want to create dynamic LinkButton for image, <img> tag is not working dynamically so I am using LinkButton with image. I don't want to provide ID to LinkButton because I want to generate more LinkButton dynamically. I am using following code in Default.aspx <%@ Page Language="C#"%> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <script runat="server"> protected void Page_Load(object sender, EventArgs e) { Response.Write(@"<asp:LinkButton runat=""server"" OnClick=""btn_click""><img src=""close-icon (1).png"" /></asp:LinkButton>"); } public void btn_click(object sender, EventArgs e) { Response.Write("HELLO"); } </script> </head> <body> <form id="form1" runat="server"> <div> </div> </form> </body> </html> I also tried to write tag code in Default.aspx.cs file but not work. It's showing me following error. Error 1 'ASP.default_aspx' does not contain a definition for 'img_Click' and no extension method 'img_Click' accepting a first argument of type 'ASP.default_aspx' could be found (are you missing a using directive or an assembly reference?) Please help me to solve this problem.

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  • Unable to use certain Fonts programatically in ASP.Net

    - by TooFat
    I am trying to programatically create a bitmap with a specified font in ASP.Net. The idea is that the text, font name, size color etc. will be passed in from variables and a bitmap of the text using the font etc will be returned. However, I have been finding that I am only able to do so using the following code with certain fonts. <div> <% string fontName = "Segoe Script"; //Change Font here System.Drawing.Bitmap bmp = new System.Drawing.Bitmap(100, 100); System.Drawing.Graphics graph = System.Drawing.Graphics.FromImage(bmp); System.Drawing.Font fnt = new System.Drawing.Font(fontName, 20); System.Drawing.SolidBrush brush = new System.Drawing.SolidBrush(System.Drawing.Color.Red); graph.DrawString("Help", fnt, brush, new System.Drawing.Point(10, 10)); bmp.Save(@"C:\Development\Path\image1.bmp"); this.Image1.ImageUrl = "http://mysite/Images/image1.bmp"; %> <asp:Label ID="Label1" runat="server" Text="Label" Font-Names="Segoe Script"> <%Response.Write("Help"); %></asp:Label> //Change font here <asp:Image ID="Image1" runat="server" /> </div> If I change the font name in the areas indicated by the comments to Arial or Verdana both the image and the label appear with the correct font. If however, I change the font name in both locations to something "Segoe Script" the Label will show up in Segoe Script but the image is in what looks like Arial.

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  • ASP.NET enum dropdownlist validation

    - by Arun Kumar
    I have got a enum public enum TypeDesc { [Description("Please Specify")] PleaseSpecify, Auckland, Wellington, [Description("Palmerston North")] PalmerstonNorth, Christchurch } I am binding this enum to drop down list using the following code on page_Load protected void Page_Load(object sender, EventArgs e) { if (TypeDropDownList.Items.Count == 0) { foreach (TypeDesc newPatient in EnumToDropDown.EnumToList<TypeDesc>()) { TypeDropDownList.Items.Add(EnumToDropDown.GetEnumDescription(newPatient)); } } } public static string GetEnumDescription(Enum value) { FieldInfo fi = value.GetType().GetField(value.ToString()); DescriptionAttribute[] attributes = (DescriptionAttribute[])fi.GetCustomAttributes(typeof(DescriptionAttribute), false); if (attributes != null && attributes.Length > 0) return attributes[0].Description; else return value.ToString(); } public static IEnumerable<T> EnumToList<T>() { Type enumType = typeof(T); // Can't use generic type constraints on value types, // so have to do check like this if (enumType.BaseType != typeof(Enum)) throw new ArgumentException("T must be of type System.Enum"); Array enumValArray = Enum.GetValues(enumType); List<T> enumValList = new List<T>(enumValArray.Length); foreach (int val in enumValArray) { enumValList.Add((T)Enum.Parse(enumType, val.ToString())); } return enumValList; } and my aspx page use the following code to validate <asp:DropDownList ID="TypeDropDownList" runat="server" > </asp:DropDownList> <asp:RequiredFieldValidator ID="TypeRequiredValidator" runat="server" ControlToValidate="TypeDropDownList" ErrorMessage="Please Select a City" Text="<img src='Styles/images/Exclamation.gif' />" ValidationGroup="city"></asp:RequiredFieldValidator> But my validation is accepting "Please Specify" as city name. I want to stop user to submit if the city is not selected.

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  • ASP.Net Session Storage provider in 3-layer architecture

    - by Tedd Hansen
    I'm implementing a custom session storage provider in ASP.Net. We have a strict 3-layer architecture and therefore the session storage needs to go through the business layer. Presentation-Business-Database. The business layer is accessed through WPF. The database is MSSQL. What I need is (in order of preference): A commercial/free/open source product that solves this. The source code of a SqlSessionStateStore (custom session store) (not the ODBC-sample on MSDN) that I can modify to use a middle layer. I've tried looking at .Net source through Reflector, but the code is not usable. Note: I understand how to do this. I am looking for working samples, preferably that has been proven to work fine under heavy load. The ODBC sample on MSDN doesn't use the (new?) stored procs that the build in SqlSessionStateStore uses - I'd like to use these if possible (decreases traffic). Edit1: To answer Simons question on more info: ASP.Net Session()-object can be stored in either InProc, ASP.Net State Service or SQL-server. In a secure 3-layer model the presentation layer (web server) does not have direct/physical access to the database layer (SQL-server). And even without the physical limitations, from an architectural standpoint you may not want this. InProc and ASP.Net State Service does not support load balancing and doesn't have fault tolerance. Therefore the only option is to access SQL through webservice middle layer (business layer).

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  • How do I get 2-way data binding to work for nested asp.net Repeater controls

    - by jimblanchard
    I have the following (trimmed) markup: <asp:Repeater ID="CostCategoryRepeater" runat="server"> <ItemTemplate> <div class="costCategory"> <asp:Repeater ID="CostRepeater" runat="server" DataSource='<%# Eval("Costs")%>'> <ItemTemplate> <tr class="oddCostRows"> <td class="costItemTextRight"><span><%# Eval("Variance", "{0:c0}")%></span></td> <td class="costItemTextRight"><input id="SupplementAmount" class="costEntryRight" type="text" value='<%# Bind("SupplementAmount")%>' runat="server" /></td> </tr> </ItemTemplate> </asp:Repeater> </div> </ItemTemplate> </asp:Repeater> The outer repeater's DataSource is set in the code-beside. I've snipped them, but there are Eval statements that wire up to the properties in the outer Repeater. Anyway, one of the fields in the inner Repeater needs to be a Bind instead of an Eval, as I want to get the values that the user types in. The SupplementAmount input element correctly receives it's value when the page loads, but on the other side, when I inspect the contents of the Costs List when the form posts back, the changes the user made aren't present. Thanks.

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  • force users to logout

    - by lipkee85
    Currently I have a client and admin webpage. There are multiple users who will login to the client page. While in admin page, when I restored the database inside the admin page, I need to logout all the users who are currently login to the client page. Any ideas how it should be done? My current language using is classic ASP. If it can be done in ASP.NET, its fine too. Thanks.

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  • Custom session state provider needed for DB storage?

    - by subt13
    I know this question is related to many others, but please bear with me. I am trying an experiment to store all information in database tables instead of the ASP.NET session. In ASP.NET 4 one can create a custom provider for session. So, again should I implement a Custom Session-State Provider or should I just disable session (in Web.config)? Thanks! From the comments my question can be misunderstood. Hopefully this tidbit will help clarify: I don't want to store the session in the database. I want to store information in the database that you would typically store in the session. One reason why: I don't want to carry around a session on every page, especially if that page doesn't care about 90 percent of the information in the session

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  • Switching to FormViewMode.Edit is very slow

    - by Tim
    When i switch an ASP.Net Formview from readonly mode to edit mode it takes more than 6 seconds(from edit to readonly takes a split second). I have no idea whats the reason for it. The EditItemTemplate contains a lot of controls(table,textboxes,dropdownlists) but in fact not more than the ItemTemplate has. Yet i have even commented out the complete FormView.DataBound where the controls are data bounded but without significant change. My ASP.Net Web Apllication is using Ajax and the Formview is completely nested in an UpdatePanel. Any suggestions or assumptions for this behaviour?

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  • Facebook Card Game? Which architecture?

    - by Ben
    I am developing a Facebook Card Game for my thesis and i am wondering which architecture fits best? I am going to develop the game using Silverlight + ASP.NET. On the one side the game should contain player vs. player card games. On the other there will be also a lot of contant similar to Mafia Wars(or any other game like that) where you just interact with the server (incl. database) I read a lot about ASP.NET MVC, Silverlight MVVM and that stuff. But what fits best for a game like that? Also i am not sure if i should go with Silverlight 4 already? I don't want to start the wrong way. I really appreciate your help.

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  • Avoiding try/catch hell in my web pages

    - by Shaun_web
    I am writing an ASP.NET website, which is a new framework for me. I find that I have a try/catch block in literally every method of my codebehind. All these try/catch blocks do is catch the exception and then pop-up an error message to the user. Isn't there some sort of global error handler in ASP.NET? It's worth noting that my error handling is within control (ASCX) pages, and I would like a way to simply get each ASCX to handle its own errors without forcing all error handling just to a single master page or a redirect...

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  • How to generate <a> tag from input fields

    - by NonProgrammer
    Using ASP.Net (in C#), I need to generate a tag that contains person's name, address, etc. I have barely any experience with ASP.NET (or .NET languages) and I am given this assignment. Could someone please guide me to correct path please? Link should look like this: https://example.com/PRR/Info/Login.aspx?SupplierId=36&RegisteredUserLogin=T000001&Mode=RegisteredLoginless&RegisteredModeFunction=AutoShowTotals&RegisteredModeFunction=AutoShowTotals&PayerCountry=FI&[email protected]&ExternalOrderId=1000123&ServiceId=286&Amount286=5000.00&PayerInfo286=T000001|10000123|type1|m&SuccessReturnURL=http://success.html&FailureReturnURL=http://failure.html&SuccessCallbackURL=http://youpay.com/p247/success.html&FailureCallbackURL=http://yourfailure.html following components/fields needs to be sent to API in order to pre-populate information for users: FirstName, LastName, SupplierID = integer, Person's userlogin (Should increment by 1. Example: person 1 = t00001. Person2 = t00002, etc.), PayerCountry, Email, amount For some reason, my management thinks that this is something a non-technical person can do! Any help would be appreciated! Thanks!

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  • CMS (Web Application OR Windows Application)

    - by Raha
    I am a little bit puzzled about something. I am creating a ASP.NET MVC eCommerce application and currently I have written all the back end in ASP.NET MVC. I was thinking if its better to write all the management in WPF instead of HTML, as its probably even less prone to be exploited by hackers. I am a Windows user so I am not really bothered about using Linux/Mac at the moment so I am quite aware that having all the back-end written in HTML will allow users to have access to the admin area using other OS. I would like to see what are the advantages and disadvantages of having WPF to manage the content of the website as its probably much easier to develop and manage (think about Live Writer).

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  • Shrink a cell (in an absolutely-positioned ASP.NET table) to fit its contents?

    - by Giffyguy
    My webpage currently looks like this: <asp:Table runat="server" style="position: absolute; left: 0%; top: 82%; right: 0%; bottom: 0%; width: 100%; height: 18%" CellPadding="0" CellSpacing="0" GridLines="Both"> <asp:TableRow> <asp:TableCell> Content1 </asp:TableCell> <asp:TableCell Width="2.5%"> </asp:TableCell> <asp:TableCell > Content2 </asp:TableCell> </asp:TableRow> </asp:Table> But I need it to look like this: "Content1" is of unknown size, and the table will have to adjust to fit it in, but without taking any unnecessary space away from "Content2." I can't use "display: table" because it isn't supported in IE7 and such, so I'm pretty much stuck using a regular table element unless there is something better out there that is supported in older browsers. Does anyone know how this can be accomplished?

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  • asp.net - updatepannel can't read innerHTML?

    - by omega
    In my asp.net page, I have a jquery sortable accordian (in an update panel) I use so that clients can re-arrange items. Then to save it, users would click a button (thats created from jquery) and it would traverse through the accoridion in the DOM, and write the info to a asp control textbox. Then invoke the click function of a asp button control, which then reads that information and saves the data. But now I decided to simplify this step, and use html agility pack in c#, so users click the asp button control (inside an update panel), and then it would get the innerHTML of the accordian. But the problem is, the html it's getting is not the reflecting the changes a user can make to the accordion (i.e. re arranging it), it the same as when the DOM was ready on page load... But note that, using javascript to write the innerHTML to a textbox, then from the c# function, I can read the up to date html from the accordian. Does anyone know why this is happening and how to get the up to data html from the accordian in c#?

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  • Why do we need Web-Api? [closed]

    - by user437973
    I was just wondering what the deal is with Asp.net Web-Api. Why did we need a separate type of controller in order to facilitate varying content types for action results? Why wasn't this capability just baked into the ASP.Net MVC base controller? Anyway, I was just wondering if there was a compelling reason to use both types of controllers within the same project, assuming that the project was being freshly created, or if this project structure was due to an inherent technical limitation. Would it be possible to have ApiControllers fulfill the purpose of an MVC Controller in all cases by just serving HTML when that is the specified accept type? It just seems to me like a lot of unnecessary repetition to have to re-implement the same types of actions using both types of controllers if you want those actions to be available to your web application through the API and through the web interface.

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  • DevConnections Slides and Samples Posted

    - by Rick Strahl
    I’ve posted the slides and samples to my DevConnections Sessions for anyone interested. I had a lot of fun with my sessions this time around mainly because the sessions picked were a little off the beaten track (well, the handlers/modules and e-commerce sessions anyway). For those of you that attended I hope you found the sessions useful. For the rest of you – you can check out the slides and samples if you like. Here’s what was covered: Introduction to jQuery with ASP.NET This session covered mostly the client side of jQuery demonstrated on a small sample page with a variety of incrementally built up examples of selection and page manipulation. This session also introduces some of the basics of AJAX communication talking to ASP.NET. When I do this session it never turns out exactly the same way and this time around the examples were on the more basic side and purely done with hands on demonstrations rather than walk throughs of more complex examples. Alas this session always feels like it needs another half an hour to get through the full sortiment of functionality. The slides and samples cover a wider variety of topics and there are many examples that demonstrate more advanced operations like interacting with WCF REST services, using client templating and building rich client only windowed interfaces. Download Low Level ASP.NET: Handlers and Modules This session was a look at the ASP.NET pipeline and it discusses some of the ASP.NET base architecture and key components from HttpRuntime on up through the various modules and handlers that make up the ASP.NET/IIS pipeline. This session is fun as there are a number of cool examples that demonstrate the power and flexibility of ASP.NET, but some of the examples were external and interfacing with other technologies so they’re not actually included in the downloadable samples. However, there are still a few cool ones in there – there’s an image resizing handler, an image overlay module that stamps images with Sample if loaded from a certain folder, an OpenID authentication module (which failed during the demo due to the crappy internet connection at DevConnections this year :-}), Response filtering using a generic filter stream component, a generic error handler and a few others. The slides cover a lot of the ASP.NET pipeline flow and various HttpRuntime components. Download Electronic Payment Processing in ASP.NET Applications This session covered the business end and integration of electronic credit card processing and PayPal. A good part of this session deals with what’s involved in payment processing, getting signed up and who you have to deal with for your merchant account. We then took a look at integration of credit card processing via some generic components provided with the session that allow processing using a unified class interface with specific implementations for several of the most common gateway providers including Authorize.NET, PayFlowPro, LinkPoint, BluePay etc. We also briefly looked at PayPal Classic implementation which provides a quick and cheap if not quite as professional mechanism for taking payments online. The samples provide the Credit Card processing wrappers for the various gateway providers as well as a PayPal helper class to generate the PayPal redirect urls as well as helper code for dealing with IPN callbacks. Download Hope some of you will find the material useful. Enjoy.© Rick Strahl, West Wind Technologies, 2005-2010Posted in ASP.NET  

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  • Microsoft and jQuery

    - by Rick Strahl
    The jQuery JavaScript library has been steadily getting more popular and with recent developments from Microsoft, jQuery is also getting ever more exposure on the ASP.NET platform including now directly from Microsoft. jQuery is a light weight, open source DOM manipulation library for JavaScript that has changed how many developers think about JavaScript. You can download it and find more information on jQuery on www.jquery.com. For me jQuery has had a huge impact on how I develop Web applications and was probably the main reason I went from dreading to do JavaScript development to actually looking forward to implementing client side JavaScript functionality. It has also had a profound impact on my JavaScript skill level for me by seeing how the library accomplishes things (and often reviewing the terse but excellent source code). jQuery made an uncomfortable development platform (JavaScript + DOM) a joy to work on. Although jQuery is by no means the only JavaScript library out there, its ease of use, small size, huge community of plug-ins and pure usefulness has made it easily the most popular JavaScript library available today. As a long time jQuery user, I’ve been excited to see the developments from Microsoft that are bringing jQuery to more ASP.NET developers and providing more integration with jQuery for ASP.NET’s core features rather than relying on the ASP.NET AJAX library. Microsoft and jQuery – making Friends jQuery is an open source project but in the last couple of years Microsoft has really thrown its weight behind supporting this open source library as a supported component on the Microsoft platform. When I say supported I literally mean supported: Microsoft now offers actual tech support for jQuery as part of their Product Support Services (PSS) as jQuery integration has become part of several of the ASP.NET toolkits and ships in several of the default Web project templates in Visual Studio 2010. The ASP.NET MVC 3 framework (still in Beta) also uses jQuery for a variety of client side support features including client side validation and we can look forward toward more integration of client side functionality via jQuery in both MVC and WebForms in the future. In other words jQuery is becoming an optional but included component of the ASP.NET platform. PSS support means that support staff will answer jQuery related support questions as part of any support incidents related to ASP.NET which provides some piece of mind to some corporate development shops that require end to end support from Microsoft. In addition to including jQuery and supporting it, Microsoft has also been getting involved in providing development resources for extending jQuery’s functionality via plug-ins. Microsoft’s last version of the Microsoft Ajax Library – which is the successor to the native ASP.NET AJAX Library – included some really cool functionality for client templates, databinding and localization. As it turns out Microsoft has rebuilt most of that functionality using jQuery as the base API and provided jQuery plug-ins of these components. Very recently these three plug-ins were submitted and have been approved for inclusion in the official jQuery plug-in repository and been taken over by the jQuery team for further improvements and maintenance. Even more surprising: The jQuery-templates component has actually been approved for inclusion in the next major update of the jQuery core in jQuery V1.5, which means it will become a native feature that doesn’t require additional script files to be loaded. Imagine this – an open source contribution from Microsoft that has been accepted into a major open source project for a core feature improvement. Microsoft has come a long way indeed! What the Microsoft Involvement with jQuery means to you For Microsoft jQuery support is a strategic decision that affects their direction in client side development, but nothing stopped you from using jQuery in your applications prior to Microsoft’s official backing and in fact a large chunk of developers did so readily prior to Microsoft’s announcement. Official support from Microsoft brings a few benefits to developers however. jQuery support in Visual Studio 2010 means built-in support for jQuery IntelliSense, automatically added jQuery scripts in many projects types and a common base for client side functionality that actually uses what most developers are already using. If you have already been using jQuery and were worried about straying from the Microsoft line and their internal Microsoft Ajax Library – worry no more. With official support and the change in direction towards jQuery Microsoft is now following along what most in the ASP.NET community had already been doing by using jQuery, which is likely the reason for Microsoft’s shift in direction in the first place. ASP.NET AJAX and the Microsoft AJAX Library weren’t bad technology – there was tons of useful functionality buried in these libraries. However, these libraries never got off the ground, mainly because early incarnations were squarely aimed at control/component developers rather than application developers. For all the functionality that these controls provided for control developers they lacked in useful and easily usable application developer functionality that was easily accessible in day to day client side development. The result was that even though Microsoft shipped support for these tools in the box (in .NET 3.5 and 4.0), other than for the internal support in ASP.NET for things like the UpdatePanel and the ASP.NET AJAX Control Toolkit as well as some third party vendors, the Microsoft client libraries were largely ignored by the developer community opening the door for other client side solutions. Microsoft seems to be acknowledging developer choice in this case: Many more developers were going down the jQuery path rather than using the Microsoft built libraries and there seems to be little sense in continuing development of a technology that largely goes unused by the majority of developers. Kudos for Microsoft for recognizing this and gracefully changing directions. Note that even though there will be no further development in the Microsoft client libraries they will continue to be supported so if you’re using them in your applications there’s no reason to start running for the exit in a panic and start re-writing everything with jQuery. Although that might be a reasonable choice in some cases, jQuery and the Microsoft libraries work well side by side so that you can leave existing solutions untouched even as you enhance them with jQuery. The Microsoft jQuery Plug-ins – Solid Core Features One of the most interesting developments in Microsoft’s embracing of jQuery is that Microsoft has started contributing to jQuery via standard mechanism set for jQuery developers: By submitting plug-ins. Microsoft took some of the nicest new features of the unpublished Microsoft Ajax Client Library and re-wrote these components for jQuery and then submitted them as plug-ins to the jQuery plug-in repository. Accepted plug-ins get taken over by the jQuery team and that’s exactly what happened with the three plug-ins submitted by Microsoft with the templating plug-in even getting slated to be published as part of the jQuery core in the next major release (1.5). The following plug-ins are provided by Microsoft: jQuery Templates – a client side template rendering engine jQuery Data Link – a client side databinder that can synchronize changes without code jQuery Globalization – provides formatting and conversion features for dates and numbers The first two are ports of functionality that was slated for the Microsoft Ajax Library while functionality for the globalization library provides functionality that was already found in the original ASP.NET AJAX library. To me all three plug-ins address a pressing need in client side applications and provide functionality I’ve previously used in other incarnations, but with more complete implementations. Let’s take a close look at these plug-ins. jQuery Templates http://api.jquery.com/category/plugins/templates/ Client side templating is a key component for building rich JavaScript applications in the browser. Templating on the client lets you avoid from manually creating markup by creating DOM nodes and injecting them individually into the document via code. Rather you can create markup templates – similar to the way you create classic ASP server markup – and merge data into these templates to render HTML which you can then inject into the document or replace existing content with. Output from templates are rendered as a jQuery matched set and can then be easily inserted into the document as needed. Templating is key to minimize client side code and reduce repeated code for rendering logic. Instead a single template can be used in many places for updating and adding content to existing pages. Further if you build pure AJAX interfaces that rely entirely on client rendering of the initial page content, templates allow you to a use a single markup template to handle all rendering of each specific HTML section/element. I’ve used a number of different client rendering template engines with jQuery in the past including jTemplates (a PHP style templating engine) and a modified version of John Resig’s MicroTemplating engine which I built into my own set of libraries because it’s such a commonly used feature in my client side applications. jQuery templates adds a much richer templating model that allows for sub-templates and access to the data items. Like John Resig’s original Micro Template engine, the core basics of the templating engine create JavaScript code which means that templates can include JavaScript code. To give you a basic idea of how templates work imagine I have an application that downloads a set of stock quotes based on a symbol list then displays them in the document. To do this you can create an ‘item’ template that describes how each of the quotes is renderd as a template inside of the document: <script id="stockTemplate" type="text/x-jquery-tmpl"> <div id="divStockQuote" class="errordisplay" style="width: 500px;"> <div class="label">Company:</div><div><b>${Company}(${Symbol})</b></div> <div class="label">Last Price:</div><div>${LastPrice}</div> <div class="label">Net Change:</div><div> {{if NetChange > 0}} <b style="color:green" >${NetChange}</b> {{else}} <b style="color:red" >${NetChange}</b> {{/if}} </div> <div class="label">Last Update:</div><div>${LastQuoteTimeString}</div> </div> </script> The ‘template’ is little more than HTML with some markup expressions inside of it that define the template language. Notice the embedded ${} expressions which reference data from the quote objects returned from an AJAX call on the server. You can embed any JavaScript or value expression in these template expressions. There are also a number of structural commands like {{if}} and {{each}} that provide for rudimentary logic inside of your templates as well as commands ({{tmpl}} and {{wrap}}) for nesting templates. You can find more about the full set of markup expressions available in the documentation. To load up this data you can use code like the following: <script type="text/javascript"> //var Proxy = new ServiceProxy("../PageMethods/PageMethodsService.asmx/"); $(document).ready(function () { $("#btnGetQuotes").click(GetQuotes); }); function GetQuotes() { var symbols = $("#txtSymbols").val().split(","); $.ajax({ url: "../PageMethods/PageMethodsService.asmx/GetStockQuotes", data: JSON.stringify({ symbols: symbols }), // parameter map type: "POST", // data has to be POSTed contentType: "application/json", timeout: 10000, dataType: "json", success: function (result) { var quotes = result.d; var jEl = $("#stockTemplate").tmpl(quotes); $("#quoteDisplay").empty().append(jEl); }, error: function (xhr, status) { alert(status + "\r\n" + xhr.responseText); } }); }; </script> In this case an ASMX AJAX service is called to retrieve the stock quotes. The service returns an array of quote objects. The result is returned as an object with the .d property (in Microsoft service style) that returns the actual array of quotes. The template is applied with: var jEl = $("#stockTemplate").tmpl(quotes); which selects the template script tag and uses the .tmpl() function to apply the data to it. The result is a jQuery matched set of elements that can then be appended to the quote display element in the page. The template is merged against an array in this example. When the result is an array the template is automatically applied to each each array item. If you pass a single data item – like say a stock quote – the template works exactly the same way but is applied only once. Templates also have access to a $data item which provides the current data item and information about the tempalte that is currently executing. This makes it possible to keep context within the context of the template itself and also to pass context from a parent template to a child template which is very powerful. Templates can be evaluated by using the template selector and calling the .tmpl() function on the jQuery matched set as shown above or you can use the static $.tmpl() function to provide a template as a string. This allows you to dynamically create templates in code or – more likely – to load templates from the server via AJAX calls. In short there are options The above shows off some of the basics, but there’s much for functionality available in the template engine. Check the documentation link for more information and links to additional examples. The plug-in download also comes with a number of examples that demonstrate functionality. jQuery templates will become a native component in jQuery Core 1.5, so it’s definitely worthwhile checking out the engine today and get familiar with this interface. As much as I’m stoked about templating becoming part of the jQuery core because it’s such an integral part of many applications, there are also a couple shortcomings in the current incarnation: Lack of Error Handling Currently if you embed an expression that is invalid it’s simply not rendered. There’s no error rendered into the template nor do the various  template functions throw errors which leaves finding of bugs as a runtime exercise. I would like some mechanism – optional if possible – to be able to get error info of what is failing in a template when it’s rendered. No String Output Templates are always rendered into a jQuery matched set and there’s no way that I can see to directly render to a string. String output can be useful for debugging as well as opening up templating for creating non-HTML string output. Limited JavaScript Access Unlike John Resig’s original MicroTemplating Engine which was entirely based on JavaScript code generation these templates are limited to a few structured commands that can ‘execute’. There’s no code execution inside of script code which means you’re limited to calling expressions available in global objects or the data item passed in. This may or may not be a big deal depending on the complexity of your template logic. Error handling has been discussed quite a bit and it’s likely there will be some solution to that particualar issue by the time jQuery templates ship. The others are relatively minor issues but something to think about anyway. jQuery Data Link http://api.jquery.com/category/plugins/data-link/ jQuery Data Link provides the ability to do two-way data binding between input controls and an underlying object’s properties. The typical scenario is linking a textbox to a property of an object and have the object updated when the text in the textbox is changed and have the textbox change when the value in the object or the entire object changes. The plug-in also supports converter functions that can be applied to provide the conversion logic from string to some other value typically necessary for mapping things like textbox string input to say a number property and potentially applying additional formatting and calculations. In theory this sounds great, however in reality this plug-in has some serious usability issues. Using the plug-in you can do things like the following to bind data: person = { firstName: "rick", lastName: "strahl"}; $(document).ready( function() { // provide for two-way linking of inputs $("form").link(person); // bind to non-input elements explicitly $("#objFirst").link(person, { firstName: { name: "objFirst", convertBack: function (value, source, target) { $(target).text(value); } } }); $("#objLast").link(person, { lastName: { name: "objLast", convertBack: function (value, source, target) { $(target).text(value); } } }); }); This code hooks up two-way linking between a couple of textboxes on the page and the person object. The first line in the .ready() handler provides mapping of object to form field with the same field names as properties on the object. Note that .link() does NOT bind items into the textboxes when you call .link() – changes are mapped only when values change and you move out of the field. Strike one. The two following commands allow manual binding of values to specific DOM elements which is effectively a one-way bind. You specify the object and a then an explicit mapping where name is an ID in the document. The converter is required to explicitly assign the value to the element. Strike two. You can also detect changes to the underlying object and cause updates to the input elements bound. Unfortunately the syntax to do this is not very natural as you have to rely on the jQuery data object. To update an object’s properties and get change notification looks like this: function updateFirstName() { $(person).data("firstName", person.firstName + " (code updated)"); } This works fine in causing any linked fields to be updated. In the bindings above both the firstName input field and objFirst DOM element gets updated. But the syntax requires you to use a jQuery .data() call for each property change to ensure that the changes are tracked properly. Really? Sure you’re binding through multiple layers of abstraction now but how is that better than just manually assigning values? The code savings (if any) are going to be minimal. As much as I would like to have a WPF/Silverlight/Observable-like binding mechanism in client script, this plug-in doesn’t help much towards that goal in its current incarnation. While you can bind values, the ‘binder’ is too limited to be really useful. If initial values can’t be assigned from the mappings you’re going to end up duplicating work loading the data using some other mechanism. There’s no easy way to re-bind data with a different object altogether since updates trigger only through the .data members. Finally, any non-input elements have to be bound via code that’s fairly verbose and frankly may be more voluminous than what you might write by hand for manual binding and unbinding. Two way binding can be very useful but it has to be easy and most importantly natural. If it’s more work to hook up a binding than writing a couple of lines to do binding/unbinding this sort of thing helps very little in most scenarios. In talking to some of the developers the feature set for Data Link is not complete and they are still soliciting input for features and functionality. If you have ideas on how you want this feature to be more useful get involved and post your recommendations. As it stands, it looks to me like this component needs a lot of love to become useful. For this component to really provide value, bindings need to be able to be refreshed easily and work at the object level, not just the property level. It seems to me we would be much better served by a model binder object that can perform these binding/unbinding tasks in bulk rather than a tool where each link has to be mapped first. I also find the choice of creating a jQuery plug-in questionable – it seems a standalone object – albeit one that relies on the jQuery library – would provide a more intuitive interface than the current forcing of options onto a plug-in style interface. Out of the three Microsoft created components this is by far the least useful and least polished implementation at this point. jQuery Globalization http://github.com/jquery/jquery-global Globalization in JavaScript applications often gets short shrift and part of the reason for this is that natively in JavaScript there’s little support for formatting and parsing of numbers and dates. There are a number of JavaScript libraries out there that provide some support for globalization, but most are limited to a particular portion of globalization. As .NET developers we’re fairly spoiled by the richness of APIs provided in the framework and when dealing with client development one really notices the lack of these features. While you may not necessarily need to localize your application the globalization plug-in also helps with some basic tasks for non-localized applications: Dealing with formatting and parsing of dates and time values. Dates in particular are problematic in JavaScript as there are no formatters whatsoever except the .toString() method which outputs a verbose and next to useless long string. With the globalization plug-in you get a good chunk of the formatting and parsing functionality that the .NET framework provides on the server. You can write code like the following for example to format numbers and dates: var date = new Date(); var output = $.format(date, "MMM. dd, yy") + "\r\n" + $.format(date, "d") + "\r\n" + // 10/25/2010 $.format(1222.32213, "N2") + "\r\n" + $.format(1222.33, "c") + "\r\n"; alert(output); This becomes even more useful if you combine it with templates which can also include any JavaScript expressions. Assuming the globalization plug-in is loaded you can create template expressions that use the $.format function. Here’s the template I used earlier for the stock quote again with a couple of formats applied: <script id="stockTemplate" type="text/x-jquery-tmpl"> <div id="divStockQuote" class="errordisplay" style="width: 500px;"> <div class="label">Company:</div><div><b>${Company}(${Symbol})</b></div> <div class="label">Last Price:</div> <div>${$.format(LastPrice,"N2")}</div> <div class="label">Net Change:</div><div> {{if NetChange > 0}} <b style="color:green" >${NetChange}</b> {{else}} <b style="color:red" >${NetChange}</b> {{/if}} </div> <div class="label">Last Update:</div> <div>${$.format(LastQuoteTime,"MMM dd, yyyy")}</div> </div> </script> There are also parsing methods that can parse dates and numbers from strings into numbers easily: alert($.parseDate("25.10.2010")); alert($.parseInt("12.222")); // de-DE uses . for thousands separators As you can see culture specific options are taken into account when parsing. The globalization plugin provides rich support for a variety of locales: Get a list of all available cultures Query cultures for culture items (like currency symbol, separators etc.) Localized string names for all calendar related items (days of week, months) Generated off of .NET’s supported locales In short you get much of the same functionality that you already might be using in .NET on the server side. The plugin includes a huge number of locales and an Globalization.all.min.js file that contains the text defaults for each of these locales as well as small locale specific script files that define each of the locale specific settings. It’s highly recommended that you NOT use the huge globalization file that includes all locales, but rather add script references to only those languages you explicitly care about. Overall this plug-in is a welcome helper. Even if you use it with a single locale (like en-US) and do no other localization, you’ll gain solid support for number and date formatting which is a vital feature of many applications. Changes for Microsoft It’s good to see Microsoft coming out of its shell and away from the ‘not-built-here’ mentality that has been so pervasive in the past. It’s especially good to see it applied to jQuery – a technology that has stood in drastic contrast to Microsoft’s own internal efforts in terms of design, usage model and… popularity. It’s great to see that Microsoft is paying attention to what customers prefer to use and supporting the customer sentiment – even if it meant drastically changing course of policy and moving into a more open and sharing environment in the process. The additional jQuery support that has been introduced in the last two years certainly has made lives easier for many developers on the ASP.NET platform. It’s also nice to see Microsoft submitting proposals through the standard jQuery process of plug-ins and getting accepted for various very useful projects. Certainly the jQuery Templates plug-in is going to be very useful to many especially since it will be baked into the jQuery core in jQuery 1.5. I hope we see more of this type of involvement from Microsoft in the future. Kudos!© Rick Strahl, West Wind Technologies, 2005-2010Posted in jQuery  ASP.NET  

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