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  • Submitting form with links and jquery

    - by Eagletrophy
    Me again, I have a question I would like to ask as a followup. to submit a form using a link powered by jquery is what I am curious about. do I just bind a click event to the link in the live() event for eg and use a submit() added to the click? God bless

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  • How to navigate around a '[' in JSON.

    - by Kyle
    I'm new to JSON and moving around in it in jQuery. I'm fine until I hit a '[', as in: "gd$when": [{ "startTime": "2006-11-15", "endTime": "2006-11-17", "gd$reminder": [{"minutes": "10"}] }], I tried to do a eventTime = event["gd$when"]["startTime"]; to get to the 'startTime' (Yes, event is the variable for ajax stuff, it's all working fine until I hit the '[') Thanks for any help.

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  • session fixation

    - by markiv
    Hi All, I am new to web development, and trying to get a hold on security issues. I went through this article on http://guides.rubyonrails.org/security.html these are some of the steps the author has mentioned how an attacker fixes session. 1. The attacker creates a valid session id: He loads the login page of the web application where he wants to fix the session, and takes the session id in the cookie from the response (see number 1 and 2 in the image). 2. He possibly maintains the session. Expiring sessions, for example every 20 minutes, greatly reduces the time-frame for attack. Therefore he accesses the web application from time to time in order to keep the session alive. 3. Now the attacker will force the user’s browser into using this session id (see number 3 in the image). As you may not change a cookie of another domain (because of the same origin policy), the attacker has to run a JavaScript from the domain of the target web application. Injecting the JavaScript code into the application by XSS accomplishes this attack. Here is an example: <script>?document.cookie="_session_id=16d5b78abb28e3d6206b60f22a03c8d9";?</script>. Read more about XSS and injection later on. 4. The attacker lures the victim to the infected page with the JavaScript code. By viewing the page, the victim’s browser will change the session id to the trap session id. 5. As the new trap session is unused, the web application will require the user to authenticate. 6. From now on, the victim and the attacker will co-use the web application with the same session: The session became valid and the victim didn’t notice the attack. I dont understand couple of points. i) why is user made to login in step5, since session is sent through. ii) I saw possible solutions on wiki, like user properties check and others why cant we just reset the session for the user whoever is login in when they enter username and password in step5? Thanks in advance Markiv

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  • Are python list comprehensions always a good programming practice?

    - by dln385
    To make the question clear, I'll use a specific example. I have a list of college courses, and each course has a few fields (all of which are strings). The user gives me a string of search terms, and I return a list of courses that match all of the search terms. This can be done in a single list comprehension or a few nested for loops. Here's the implementation. First, the Course class: class Course: def __init__(self, date, title, instructor, ID, description, instructorDescription, *args): self.date = date self.title = title self.instructor = instructor self.ID = ID self.description = description self.instructorDescription = instructorDescription self.misc = args Every field is a string, except misc, which is a list of strings. Here's the search as a single list comprehension. courses is the list of courses, and query is the string of search terms, for example "history project". def searchCourses(courses, query): terms = query.lower().strip().split() return tuple(course for course in courses if all( term in course.date.lower() or term in course.title.lower() or term in course.instructor.lower() or term in course.ID.lower() or term in course.description.lower() or term in course.instructorDescription.lower() or any(term in item.lower() for item in course.misc) for term in terms)) You'll notice that a complex list comprehension is difficult to read. I implemented the same logic as nested for loops, and created this alternative: def searchCourses2(courses, query): terms = query.lower().strip().split() results = [] for course in courses: for term in terms: if (term in course.date.lower() or term in course.title.lower() or term in course.instructor.lower() or term in course.ID.lower() or term in course.description.lower() or term in course.instructorDescription.lower()): break for item in course.misc: if term in item.lower(): break else: continue break else: continue results.append(course) return tuple(results) That logic can be hard to follow too. I have verified that both methods return the correct results. Both methods are nearly equivalent in speed, except in some cases. I ran some tests with timeit, and found that the former is three times faster when the user searches for multiple uncommon terms, while the latter is three times faster when the user searches for multiple common terms. Still, this is not a big enough difference to make me worry. So my question is this: which is better? Are list comprehensions always the way to go, or should complicated statements be handled with nested for loops? Or is there a better solution altogether?

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  • pygtk combobox 'changed' does not work

    - by joven
    I'm using pygtk then i used gtk.Combobox when i try to connect on chenged event its working but when i try to select an item that is already selected the changed method does not triggered since the selection does not changed.. so my question is how to connect the changed event even thought the selection does not changed tnx in advance

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  • How to create a Link that supplies its own Markup?

    - by Aranian
    I'm trying to create a link that will hide or show a part of my page. The link should be reusable and display one of two images, depending on state. Adding the two subcomponents on every page where I use the link is kind of clunky so I wanted to create a component that behaves like a link while automatically adding its content. This is the Link component: public class ToggleVisibilityLink extends AjaxFallbackLink<Boolean> { public ToggleVisibilityLink(final String id, final IModel<Boolean> model) { super(id, model); setOutputMarkupId(true); add(new Image("collapseImage") { @Override public boolean isVisible() { return !getModelObject(); } }); add(new Image("expandImage") { @Override public boolean isVisible() { return getModelObject(); } }); } @Override public void onClick(final AjaxRequestTarget target) { setModelObject(!getModelObject()); if (target != null) { target.add(this); send(this.getParent(), Broadcast.EXACT, target); } } } And this is how I currently use it in HTML (this is added to the page or panel where I use the link): <a href="#" wicket:id="collapseExpandLink" class="collapseExpandLink"> <wicket:link> <img src="collapse.png" wicket:id="collapseImage" class="collapseExpandImage collapse"> </wicket:link> <wicket:link> <img src="expand.png" wicket:id="expandImage" class="collapseExpandImage expand"> </wicket:link> </a> And the corresponding Java call: add(new ToggleVisibilityLink("collapseExpandLink", new PropertyModel(this, "hidden"))); But I want to be able to skip the body inside the link as one would have to know about the internals of ToggleVisibilityLink. I experimented with IMarkupResourceStreamProvider, using Dynamic markup in Wicket as a starting point. By googling I found another example where the poster was only able to get that to work when using a Panel, and I was able to do that as well. But I'd really like to keep the link and not package it inside a Panel, as I would not be able to style the link in the markup. I'm also open to alternatives to encapsulate the link and its body.

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  • removeClass doesn't work on the second DIV tag

    - by kwokwai
    Hi all, I am learning JQuery and writing a simple data validation for the two fields in a HTML form: <FORM name="addpost" id="addpost" method="post" action="/add"> <TABLE BORDER=0 width="100%"> <TR> <TD>Topic</TD> <TD> <DIV ID="topic"> <INPUT type=text name="topic" id="topic" size="72" maxlength="108"/> </DIV> </TD> </TR> <TR> <TD>Comments</TD> <TD> <DIV ID="topiccontent"> <TEXTAREA rows="12" cols="48" name="content" ID="content"> </TEXTAREA> </DIV> </TD> </TR> <TR> <TD> <INPUT type="submit" value="Send"> </TD> </TR> </TABLE> </FORM> Here is the JQuery script for checking the data input from the form above: $('#addpost').submit(function(){ if($('#topic').val()==""){ $('#topic').addClass('hierror'); return false;} else{$('#topic').removeClass('hierror');} if($('#topiccontent').val()==""){ $('#topiccontent').addClass('hierror'); return false;} else{$('#topiccontent').removeClass('hierror');} }); Here is the CSS for the hierror class: .hierror{border-style:solid; border-width:12px; border-color:#FF0000;} ('#topic').removeClass('hierror') works but ('#topiccontent').removeClass('hierror') doesn't. Could you help me please?

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  • Manipulating values from database table with php

    - by charliecodex23
    I currently have 5 tables in MySQL database. Some of them share foreign keys and are interdependent of each other. I am displaying classes accordingly to their majors. Each class is taught during the fall, spring or all_year. In my database I have a table named semester which has an id, year, and semester fields. The semester field in particular is a tinyint that has three values 0, 1, 2. This signifies the fall, spring or all_year. When I display the query instead of having it show 0 or 1 or 2 can I have it show fall, spring etc? Extra: How can I add space to the end of each loop so the data doesn't look clustered? Key 0 Fall 1 Spring 2 All-year PHP <? try { $pdo = new PDO ("mysql:host=$hostname;dbname=$dbname","$username","$pw"); } catch (PDOException $e) { echo "Failed to get DB handle: " . $e->getMessage() . "\n"; exit; } $query = $pdo->prepare("SELECT course.name, course.code, course.description, course.hours, semester.semester, semester.year FROM course LEFT JOIN major_course_xref ON course.id = major_course_xref.course_id LEFT JOIN major ON major.id = major_course_xref.major_id LEFT JOIN course_semester_xref ON course.id = course_semester_xref.course_id LEFT JOIN semester ON course_semester_xref.semester_id = semester.id"); $query->execute(); if ($query->execute()){ while ($row = $query->fetch(PDO::FETCH_ASSOC)){ print $row['name'] . "<br>"; print $row['code'] . "<br>"; print $row['description'] . "<br>"; print $row['hours'] . " hrs.<br>"; print $row['semester'] . "<br>"; print $row['year'] . "<br>"; } } else echo 'Could not fetch results.'; unset($pdo); unset($query); ?> Current Display Computer Programming I CPSC1400 Introduction to disciplined, object-oriented program development. 4 hrs. 0 2013 Desire Display Computer Programming I CPSC1400 Introduction to disciplined, object-oriented program development. 4 hrs. Fall 2013

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  • Controlling images of nodes in a TreeView

    - by ET
    I am trying to make a folder explorer using TreeView control. now, I added an ImageList with two images - one for a folder and the other for selected folder. I used the 'BeforeExpand' event to change the icon of the current node (folder). The problem is that I dont know how to change it back when the user selects other folder... what event can I use? Maybe I dont use it right... ?

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  • Jquery prevent dragging of text value

    - by ipr101
    I have a html textbox on which I've bound a function via jQuery to the paste event to prevent users pasting a value into the textbox. This functionality works well. However it is possible to select some text from another textbox on the page and drag it into the textbox in which pastes are prevented. Is there a jQuery event that I can bind to that will prevent users dragging text into the texbox?

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  • submit form - jquery problem

    - by lannoo
    Hello all, I am trying to raise a click event on a submit button in a html form. I use the .click() jquery to catch the click event and return true at the end of the function. When I click on the submit button, the jquery functions are raised and a callback is executed, but the $_POST array is empty. How can I fix this?

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  • jquery not select?

    - by acidzombie24
    i have a click event for $('#blah div'). div has text inside of it (not inside a div, span, p, etc) and has a textarea in it. The textarea is triggering the event as well, how do i make it only trigger when i click the text and ignore the textarea?

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  • $.post() in jQuery not working as expected

    - by Bunny Rabbit
    $('a').click(function(event){ $('body').html('loading...'); $.post('www.sitename.com/hello',{site:"http//:www.google.com"},function(data) { alert(data); }); event.preventDefault(); }); I am using the above script to override the default behaviour of the links .The site reffred here returns the html of the 'site' paraeter.but the page just stops after printing loading...

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  • Client Side pagination with jQuery

    - by TheNone
    I have tried to write a script for pagination contents of an element with jQuery: <script type="text/javascript"> $(document).ready(function(){ var per_page = 2; var num_item = $('#en1').children().size(); var num_page = Math.ceil(num_item/per_page); $('#current_page').val(0); $('#per_page').val(per_page); var navigation_html = ''; var current = 0; while(num_page > current){ navigation_html += '<a class="page_link" href="javascript:paginate(' + current +')" longdesc="' + current +'">'+ (current + 1) +'</a>'; current++; } $('#page_navigation').html(navigation_html); $('#page_navigation .page_link:first').addClass('active_page'); $('#en1').children().css('display', 'none'); $('#en1').children().slice(0, per_page).css('display', 'block'); }); function paginate(page_num){ var per_page = parseInt($('#per_page').val()); start = page_num * per_page; finish= start + per_page; $('#en1').children().css('display', 'none').slice(start, finish).css('display', 'block'); $('.page_link[longdesc=' + page_num +']').addClass('active_page').siblings('.active_page').removeClass('active_page'); $('#current_page').val(page_num); } </script> http://jsfiddle.net/kqfyL/9/ This script paginate the contents of element by id "en1". I want to paginate 4-5 element (en2, en3, ...). When I insert code inside o document ready in a function, pagination doesnt work: function init(myId){ var ID = document.getElementById("myId"); var per_page = 6; var num_item = $(ID).children().size(); var num_page = Math.ceil(num_item/per_page); $('#current_page').val(0); $('#per_page').val(per_page); var navigation_html = ''; var current = 0; while(num_page > current){ navigation_html += '<a class="page_link" href="javascript:paginate(' + current +')" longdesc="' + current +'">'+ (current + 1) +'</a>'; current++; } $('#page_navigation').html(navigation_html); $('#page_navigation .page_link:first').addClass('active_page'); $('#ID').children().css('display', 'none'); $('#ID').children().slice(0, per_page).css('display', 'block'); } init(en1); What is wrong in init function? Thanks in advance

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  • NullPointerException while trying to bind at SimpleCursorAdapter

    - by hrskrs
    I have asked a question before where i found my mistake. However now i am facing with another problem. I have checked all the similar errors asked on StackOverflow but without success.Any help is appriciated. The idea here is that i am getting image names from DB so depending on those names images from Drawable folder will be shown in a listView together with a description but im getting an error of NullPointException at setViewValue. Here is the code snippet: private void populateListView() { ListView customListView = (ListView)findViewById(R.id.lvCustom); Cursor cursor = DBhelper.getAllimages(); startManagingCursor(cursor); String[] from = { DBhelper.COLUMN_PIC_URL, DBhelper.COLUMN_PIC_DESC}; int[] to = {R.id.ivImg, R.id.tvTitle}; SimpleCursorAdapter cursorAdapter = new SimpleCursorAdapter(this, R.layout.custom_listview_row, cursor, from, to, 0); cursorAdapter.setViewBinder(new ViewBinder() { @Override public boolean setViewValue(View view, Cursor cursor, int columnIndex) { ImageView imageImageView = (ImageView)findViewById(R.id.ivImg); String[] imgNames = new String[cursor.getCount()]; int[] imgResourceIds = new int[cursor.getCount()]; for(int i=0; i<cursor.getCount(); i++){ imgNames[i] = cursor.getString(cursor.getColumnIndex(DBhelper.COLUMN_PIC_URL)); imgResourceIds[i] = getResources().getIdentifier(imgNames[i], "drawable", getPackageName()); imageImageView.setImageResource(imgResourceIds[i]); cursor.moveToNext(); } return true; } }); customListView.setAdapter(cursorAdapter); } Here is the Error from LogCat: I have tried to log the output of imgNames[i] where it returns the url pic from the DB correctly and imgResourceIds[i] where it return the image resource id correctly also(it does not return NULL but something like: 295731). But it stops at imageImageView.setImageResource(imgResourceIds[i]); To see from where that NullPointerException is coming, i commented out imageImageView.setImageResource(imgResourceIds[i]);. This time imageNames(those with a TAG) and imgResourceIds(those system printed out) came correctly but doubled, when i removed cursor.MoveToNext() last row were doubled. Here is the screen shot of that: I have tried all the suggestions on stack about gettin a NullException but without success. Any idea where i am doing mistake?

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  • Fullcalendar on IPhone

    - by Iphone novice
    Hello all, Is it possible to use fullcalendar on iphone native app reading events from servlet on a remote server? Features required are Month, Week and Day view. No need of adding, editing or deleting events. Clicking on event display the summary of the event. I would be very happy if fullcalendar is capable of the same, if no what are the other solutions. Expecting your guidance. Thanks in advance

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  • Ajax posting to PHP

    - by JQonfused
    Hi guys, I'm testing a jQuery ajax post method on a local Apache 2.2 server with PHP 5.3 (totally new at this). Here are the files, all in the same folder. html body (jQuery library included in head): <form id="postForm" method="post"> <label for="name">Input Name</label> <input type="text" name="name" id="name" /><br /> <label for="age">Input Age</label> <input type="text" name="age" id="age" /><br /> <input type="submit" value="Submit" id="submitBtn" /> </form> <div id="resultDisplay"></div> <script src="queryRequest.js"></script> queryRequest.js $(document).ready(function(){ $('#s').focus(); $('#postForm').submit(function(){ var name = $('#name').val(); var age = $('#age').val(); var URL = "post.php"; $.ajax({ type:'POST', url: URL, datatype:'json', data:{'name': name ,'age': age}, success: function(data){ $('#resultDisplay').append("Value returned.<br />name: "+data.name+" age: "+data.age); }, error: function() { $('resultDisplay').append("ERROR!") } }); }); }); post.php <?php $name = $_POST['name']; $age = $_POST['age']; $return = array('name' => $name, 'age' => $age); echo json_encode($return); ?> After inputting the two fields and pressing 'Submit', the success method is called, text appended, but the values returned from ajax post are undefined. And then after less than a second, the text fields are emptied, and the text appended to the div is gone. Doesn't seem like it's a page refresh, though, since there's no empty page flash. What's going on here? I'm sure it's a silly mistake but Firebug isn't telling me anything.

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  • jQuery if and logic

    - by danit
    I have a simple jQuery toolbar, the basic functionality is: Hover: Background change to defined value & add .active class OnClick: Move the icon down 4px, and change background of the toolbar to that of the element What I would like to do move the icon down 4px when it has the class 'active' applied, however also remove the onclick event? Somehow I need an 'IF' statement in my jQuery for the Onclick event.

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  • NHibernate BusinessRules

    - by mr0zek
    I need implement business using nhibernate ORM I have two entites Project (Id,Name,Effort) Task (Id,Name,Effort) I need update Effort in Project when Effort in Task changes. How to do it ? I have planed to use event system build in nhibernate but still don't know how to access to Project entity within Task Event

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  • How to validate if all check boxes are ticked in jQuery?

    - by Jude
    I am a beginner in jQuery and I was wondering how to validate the form before submission specifically for check boxes. I am creating a simple check list form where my user would tick a check box if he finished that step. What I am planning to do is that, the script would prevent the form submission if there is an "unticked" checkbox and highlight it with a color. Here's my code : <!doctype html> <html> <head> <meta charset="utf-8"> <title>checkbox</title> <style> .error { background-color:#F00; } .valid { background-color:#0F0; } </style> <script type="application/javascript" src="http://code.jquery.com/jquery-1.8.2.min.js"> </script> <script type="application/javascript"> function validateAll() { $(".tick").change(function(){ if ($('.tick:checked').length == $('.tick').length) { $('#container').removeClass(); $('#container').addClass('error'); } else { $('#container').removeClass(); $('#container').addClass('valid'); } }); } </script> </head> <body> <div id="container"><input class="tick" id="option1" type="checkbox"></div> <div id="container"><input class="tick" id="option1" type="checkbox"></div> <input id="button" type="button" onClick="validateAll();" value="check"> </body> </html> So what I am trying to do here is when the user clicks the button, the script will highlight all the unchecked check box with red and highlight all checked with green. However, my script is not functioning. What is wrong with my script? Any suggestions on a more efficient way to do this?

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  • mysql_query() returns returns true, but mysql_num_rows() and mysql_fetch_array() give "not a valid r

    - by zlance4012
    Here is the code in question: -----From index.php----- require_once('includes/DbConnector.php'); // Create an object (instance) of the DbConnector $connector = new DbConnector(); // Execute the query to retrieve articles $query1 = "SELECT id, title FROM articles ORDER BY id DESC LIMIT 0,5"; $result = $connector-query($query1); echo "vardump1:"; var_dump($result); echo "\n"; /(!line 17!)/ echo "Number of rows in the result of the query:".mysql_num_rows($result)."\n"; // Get an array containing the results. // Loop for each item in that array while ($row = $connector-fetchArray($result)){ echo ' '; echo $row['title']; echo ' '; -----end index.php----- -----included DbConnector.php----- $settings = SystemComponent::getSettings(); // Get the main settings from the array we just loaded $host = $settings['dbhost']; $db = $settings['dbname']; $user = $settings['dbusername']; $pass = $settings['dbpassword']; // Connect to the database $this-link = mysql_connect($host, $user, $pass); mysql_select_db($db); register_shutdown_function(array(&$this, 'close')); } //end constructor //* Function: query, Purpose: Execute a database query * function query($query) { echo "Query Statement: ".$query."\n"; $this-theQuery = $query; return mysql_query($query, $this-link) or die(mysql_error()); } //* Function: fetchArray, Purpose: Get array of query results * function fetchArray($result) { echo "<|"; var_dump($result); echo "| \n"; /(!line 50!)/$res= mysql_fetch_array($result) or die(mysql_error()); echo $res['id']."-".$res['title']."-".$res['imagelink']."-".$res['text']; return $res; } -----end DbConnector.php----- -----Output----- Query Statement: SELECT id, title FROM articles ORDER BY id DESC LIMIT 0,5 vardump1:bool(true) PHP Error Message Warning: mysql_num_rows(): supplied argument is not a valid MySQL result resource in /path to/index.php on line 17 Number of rows in the result of the query: <|bool(true) | PHP Error Message Warning: mysql_fetch_array(): supplied argument is not a valid MySQL result resource in /path to/DbConnector.php on line 50

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  • Popping a modal view from anywhere in code

    - by ConfusedNoob
    Is it possible to 'pop' a view from any point in an iOS application. For example, I want an event to trigger a view sliding in (modal) and the event can happen at any time, on any screen in the application. Also, we'd like this to be something that can be included in other projects and would prefer them not to have to do anything special to these projects (other than wire in the referenced project).

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  • Flex: cannot resize player back from Full Screen

    - by Patrick
    hi, The key event is not listened by my Flex app. Since it is really simple code, I cannot understand where the problem is... init() { stage.addEventListener(KeyboardEvent.KEY_DOWN, escHandler); } private function escHandler(event:KeyboardEvent):void { debugF.text = "ESC pressed"; } thanks

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  • Using jQuery to POST Form Data to an ASP.NET ASMX AJAX Web Service

    - by Rick Strahl
    The other day I got a question about how to call an ASP.NET ASMX Web Service or PageMethods with the POST data from a Web Form (or any HTML form for that matter). The idea is that you should be able to call an endpoint URL, send it regular urlencoded POST data and then use Request.Form[] to retrieve the posted data as needed. My first reaction was that you can’t do it, because ASP.NET ASMX AJAX services (as well as Page Methods and WCF REST AJAX Services) require that the content POSTed to the server is posted as JSON and sent with an application/json or application/x-javascript content type. IOW, you can’t directly call an ASP.NET AJAX service with regular urlencoded data. Note that there are other ways to accomplish this. You can use ASP.NET MVC and a custom route, an HTTP Handler or separate ASPX page, or even a WCF REST service that’s configured to use non-JSON inputs. However if you want to use an ASP.NET AJAX service (or Page Methods) with a little bit of setup work it’s actually quite easy to capture all the form variables on the client and ship them up to the server. The basic steps needed to make this happen are: Capture form variables into an array on the client with jQuery’s .serializeArray() function Use $.ajax() or my ServiceProxy class to make an AJAX call to the server to send this array On the server create a custom type that matches the .serializeArray() name/value structure Create extension methods on NameValue[] to easily extract form variables Create a [WebMethod] that accepts this name/value type as an array (NameValue[]) This seems like a lot of work but realize that steps 3 and 4 are a one time setup step that can be reused in your entire site or multiple applications. Let’s look at a short example that looks like this as a base form of fields to ship to the server: The HTML for this form looks something like this: <div id="divMessage" class="errordisplay" style="display: none"> </div> <div> <div class="label">Name:</div> <div><asp:TextBox runat="server" ID="txtName" /></div> </div> <div> <div class="label">Company:</div> <div><asp:TextBox runat="server" ID="txtCompany"/></div> </div> <div> <div class="label" ></div> <div> <asp:DropDownList runat="server" ID="lstAttending"> <asp:ListItem Text="Attending" Value="Attending"/> <asp:ListItem Text="Not Attending" Value="NotAttending" /> <asp:ListItem Text="Maybe Attending" Value="MaybeAttending" /> <asp:ListItem Text="Not Sure Yet" Value="NotSureYet" /> </asp:DropDownList> </div> </div> <div> <div class="label">Special Needs:<br /> <small>(check all that apply)</small></div> <div> <asp:ListBox runat="server" ID="lstSpecialNeeds" SelectionMode="Multiple"> <asp:ListItem Text="Vegitarian" Value="Vegitarian" /> <asp:ListItem Text="Vegan" Value="Vegan" /> <asp:ListItem Text="Kosher" Value="Kosher" /> <asp:ListItem Text="Special Access" Value="SpecialAccess" /> <asp:ListItem Text="No Binder" Value="NoBinder" /> </asp:ListBox> </div> </div> <div> <div class="label"></div> <div> <asp:CheckBox ID="chkAdditionalGuests" Text="Additional Guests" runat="server" /> </div> </div> <hr /> <input type="button" id="btnSubmit" value="Send Registration" /> The form includes a few different kinds of form fields including a multi-selection listbox to demonstrate retrieving multiple values. Setting up the Server Side [WebMethod] The [WebMethod] on the server we’re going to call is going to be very simple and just capture the content of these values and echo then back as a formatted HTML string. Obviously this is overly simplistic but it serves to demonstrate the simple point of capturing the POST data on the server in an AJAX callback. public class PageMethodsService : System.Web.Services.WebService { [WebMethod] public string SendRegistration(NameValue[] formVars) { StringBuilder sb = new StringBuilder(); sb.AppendFormat("Thank you {0}, <br/><br/>", HttpUtility.HtmlEncode(formVars.Form("txtName"))); sb.AppendLine("You've entered the following: <hr/>"); foreach (NameValue nv in formVars) { // strip out ASP.NET form vars like _ViewState/_EventValidation if (!nv.name.StartsWith("__")) { if (nv.name.StartsWith("txt") || nv.name.StartsWith("lst") || nv.name.StartsWith("chk")) sb.Append(nv.name.Substring(3)); else sb.Append(nv.name); sb.AppendLine(": " + HttpUtility.HtmlEncode(nv.value) + "<br/>"); } } sb.AppendLine("<hr/>"); string[] needs = formVars.FormMultiple("lstSpecialNeeds"); if (needs == null) sb.AppendLine("No Special Needs"); else { sb.AppendLine("Special Needs: <br/>"); foreach (string need in needs) { sb.AppendLine("&nbsp;&nbsp;" + need + "<br/>"); } } return sb.ToString(); } } The key feature of this method is that it receives a custom type called NameValue[] which is an array of NameValue objects that map the structure that the jQuery .serializeArray() function generates. There are two custom types involved in this: The actual NameValue type and a NameValueExtensions class that defines a couple of extension methods for the NameValue[] array type to allow for single (.Form()) and multiple (.FormMultiple()) value retrieval by name. The NameValue class is as simple as this and simply maps the structure of the array elements of .serializeArray(): public class NameValue { public string name { get; set; } public string value { get; set; } } The extension method class defines the .Form() and .FormMultiple() methods to allow easy retrieval of form variables from the returned array: /// <summary> /// Simple NameValue class that maps name and value /// properties that can be used with jQuery's /// $.serializeArray() function and JSON requests /// </summary> public static class NameValueExtensionMethods { /// <summary> /// Retrieves a single form variable from the list of /// form variables stored /// </summary> /// <param name="formVars"></param> /// <param name="name">formvar to retrieve</param> /// <returns>value or string.Empty if not found</returns> public static string Form(this NameValue[] formVars, string name) { var matches = formVars.Where(nv => nv.name.ToLower() == name.ToLower()).FirstOrDefault(); if (matches != null) return matches.value; return string.Empty; } /// <summary> /// Retrieves multiple selection form variables from the list of /// form variables stored. /// </summary> /// <param name="formVars"></param> /// <param name="name">The name of the form var to retrieve</param> /// <returns>values as string[] or null if no match is found</returns> public static string[] FormMultiple(this NameValue[] formVars, string name) { var matches = formVars.Where(nv => nv.name.ToLower() == name.ToLower()).Select(nv => nv.value).ToArray(); if (matches.Length == 0) return null; return matches; } } Using these extension methods it’s easy to retrieve individual values from the array: string name = formVars.Form("txtName"); or multiple values: string[] needs = formVars.FormMultiple("lstSpecialNeeds"); if (needs != null) { // do something with matches } Using these functions in the SendRegistration method it’s easy to retrieve a few form variables directly (txtName and the multiple selections of lstSpecialNeeds) or to iterate over the whole list of values. Of course this is an overly simple example – in typical app you’d probably want to validate the input data and save it to the database and then return some sort of confirmation or possibly an updated data list back to the client. Since this is a full AJAX service callback realize that you don’t have to return simple string values – you can return any of the supported result types (which are most serializable types) including complex hierarchical objects and arrays that make sense to your client code. POSTing Form Variables from the Client to the AJAX Service To call the AJAX service method on the client is straight forward and requires only use of little native jQuery plus JSON serialization functionality. To start add jQuery and the json2.js library to your page: <script src="Scripts/jquery.min.js" type="text/javascript"></script> <script src="Scripts/json2.js" type="text/javascript"></script> json2.js can be found here (be sure to remove the first line from the file): http://www.json.org/json2.js It’s required to handle JSON serialization for those browsers that don’t support it natively. With those script references in the document let’s hookup the button click handler and call the service: $(document).ready(function () { $("#btnSubmit").click(sendRegistration); }); function sendRegistration() { var arForm = $("#form1").serializeArray(); $.ajax({ url: "PageMethodsService.asmx/SendRegistration", type: "POST", contentType: "application/json", data: JSON.stringify({ formVars: arForm }), dataType: "json", success: function (result) { var jEl = $("#divMessage"); jEl.html(result.d).fadeIn(1000); setTimeout(function () { jEl.fadeOut(1000) }, 5000); }, error: function (xhr, status) { alert("An error occurred: " + status); } }); } The key feature in this code is the $("#form1").serializeArray();  call which serializes all the form fields of form1 into an array. Each form var is represented as an object with a name/value property. This array is then serialized into JSON with: JSON.stringify({ formVars: arForm }) The format for the parameter list in AJAX service calls is an object with one property for each parameter of the method. In this case its a single parameter called formVars and we’re assigning the array of form variables to it. The URL to call on the server is the name of the Service (or ASPX Page for Page Methods) plus the name of the method to call. On return the success callback receives the result from the AJAX callback which in this case is the formatted string which is simply assigned to an element in the form and displayed. Remember the result type is whatever the method returns – it doesn’t have to be a string. Note that ASP.NET AJAX and WCF REST return JSON data as a wrapped object so the result has a ‘d’ property that holds the actual response: jEl.html(result.d).fadeIn(1000); Slightly simpler: Using ServiceProxy.js If you want things slightly cleaner you can use the ServiceProxy.js class I’ve mentioned here before. The ServiceProxy class handles a few things for calling ASP.NET and WCF services more cleanly: Automatic JSON encoding Automatic fix up of ‘d’ wrapper property Automatic Date conversion on the client Simplified error handling Reusable and abstracted To add the service proxy add: <script src="Scripts/ServiceProxy.js" type="text/javascript"></script> and then change the code to this slightly simpler version: <script type="text/javascript"> proxy = new ServiceProxy("PageMethodsService.asmx/"); $(document).ready(function () { $("#btnSubmit").click(sendRegistration); }); function sendRegistration() { var arForm = $("#form1").serializeArray(); proxy.invoke("SendRegistration", { formVars: arForm }, function (result) { var jEl = $("#divMessage"); jEl.html(result).fadeIn(1000); setTimeout(function () { jEl.fadeOut(1000) }, 5000); }, function (error) { alert(error.message); } ); } The code is not very different but it makes the call as simple as specifying the method to call, the parameters to pass and the actions to take on success and error. No more remembering which content type and data types to use and manually serializing to JSON. This code also removes the “d” property processing in the response and provides more consistent error handling in that the call always returns an error object regardless of a server error or a communication error unlike the native $.ajax() call. Either approach works and both are pretty easy. The ServiceProxy really pays off if you use lots of service calls and especially if you need to deal with date values returned from the server  on the client. Summary Making Web Service calls and getting POST data to the server is not always the best option – ASP.NET and WCF AJAX services are meant to work with data in objects. However, in some situations it’s simply easier to POST all the captured form data to the server instead of mapping all properties from the input fields to some sort of message object first. For this approach the above POST mechanism is useful as it puts the parsing of the data on the server and leaves the client code lean and mean. It’s even easy to build a custom model binder on the server that can map the array values to properties on an object generically with some relatively simple Reflection code and without having to manually map form vars to properties and do string conversions. Keep in mind though that other approaches also abound. ASP.NET MVC makes it pretty easy to create custom routes to data and the built in model binder makes it very easy to deal with inbound form POST data in its original urlencoded format. The West Wind West Wind Web Toolkit also includes functionality for AJAX callbacks using plain POST values. All that’s needed is a Method parameter to query/form value to specify the method to be called on the server. After that the content type is completely optional and up to the consumer. It’d be nice if the ASP.NET AJAX Service and WCF AJAX Services weren’t so tightly bound to the content type so that you could more easily create open access service endpoints that can take advantage of urlencoded data that is everywhere in existing pages. It would make it much easier to create basic REST endpoints without complicated service configuration. Ah one can dream! In the meantime I hope this article has given you some ideas on how you can transfer POST data from the client to the server using JSON – it might be useful in other scenarios beyond ASP.NET AJAX services as well. Additional Resources ServiceProxy.js A small JavaScript library that wraps $.ajax() to call ASP.NET AJAX and WCF AJAX Services. Includes date parsing extensions to the JSON object, a global dataFilter for processing dates on all jQuery JSON requests, provides cleanup for the .NET wrapped message format and handles errors in a consistent fashion. Making jQuery Calls to WCF/ASMX with a ServiceProxy Client More information on calling ASMX and WCF AJAX services with jQuery and some more background on ServiceProxy.js. Note the implementation has slightly changed since the article was written. ww.jquery.js The West Wind West Wind Web Toolkit also includes ServiceProxy.js in the West Wind jQuery extension library. This version is slightly different and includes embedded json encoding/decoding based on json2.js.© Rick Strahl, West Wind Technologies, 2005-2010Posted in jQuery  ASP.NET  AJAX  

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