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  • What's the best practice for make username check like Twitter ?

    - by Space Cracker
    I develop registration form and it have username field, and it's required to be like twitter username check ( real time check ) .. i already develop as in every textbox key up I use jquery to pass textbox.Text to page that return if is username exist or not as following code : function Check() { var userName = $('#<%= TextBox1.ClientID %>').val(); if (userName.length < 3) { $('#checkUserNameDIV').html("user name must be between 3 and 20"); return; } $('#checkUserNameDIV').html('<img src="loader.gif" />'); //setTimeout("CheckExistance('" + userName + "')", 5000); CheckExistance(userName); } function CheckExistance(userName) { $.get( "JQueryPage.aspx", { name: userName }, function(result) { var msg = ""; if (result == "1") msg = "Not Exist " + '<img src="unOK.gif" />'; else if (result == "0") msg = "Exist" ; else if (result == "error") msg = "Error , try again"; $('#checkUserNameDIV').html(msg); } ); } but i don't know if is it the best way to do that ? specially i do check every keyup .. is there any design pattern for this problem or nay good practice for doing that ?

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  • Determining presence of prototype with correct return type

    - by R..
    Here's a random problem in C black magic I just came up with: Write a function that returns 1 if malloc has been prototyped to return a pointer type and 0 if malloc has a return type of int (either implicitly or due to wrong prototype), without invoking any implementation-defined or undefined behavior. I believe it's solvable, but I haven't worked out the solution. Note that calling the function cannot be necessary and in fact is not possible since calling a function with the incorrect prototype is undefined behavior. I have some ideas for ingredients but I think it makes for a better puzzle (and possibly more diverse ideas) if I leave them out for now. I don't need the solution for any immediate use, but it could be handy in configure scripts and such. Update: A better example of the usefulness (with strdup instead of malloc): #undef strdup #define strdup(x) (strdup_has_proto ? strdup((x)) : my_strdup((x))) i.e. being able to implement X_has_proto as an expression at the source level could be a portable way to use functions which a system might or might not have, and fall back on a local replacement, without needing any separate configure step.

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  • why it makes ie6 or ie8 compatible mode crash

    - by hylin
    Anybody can tell me why those code can make ie6 or ie8 compatible mode crash? PS:I know,there is so many ways to avoid this satuation, but I just want to know why. To avoid: Change class="wrapper"--class="wrapper2" or other != "wrapper" $('wrapper').style.overflow='visible'; -- setTimeout(function(){$('wrapper').style.overflow='visible';},10); Or remove any style , js operation... <!DOCTYPE html> <html> <head> <meta charset="utf-8" /> <style>.wrapper{width:975px;margin:60px auto 0}</style> </head> <body id="wrapper" style="overflow:hidden;"> <div id="overlay" style="position:absolute;"></div> <div class="wrapper"> <input type="text" id="input1"/> <a id="btn" href="javascript:;">test</a> </div> <script type="text/javascript"> $('btn').onclick = function(){ $('overlay').style.display='none'; $('wrapper').style.overflow='visible'; $("input1").focus(); } function $(s){ return document.getElementById(s); } </script> </body> </html>

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  • jquery an div tags used in a ordered list

    - by shan2on
    hello everyone, i'm not sure where my errors are lying but here is my scenario... i have an un-ordered list in html that handles my main link bar... <ul id="navlist"> <li><a href="/" id="current">home</a></li> <li><a href="#" id="search">search</a></li> <li><a href="#" id="users">login</a></li> </ul> and what i want done is to call each id and have jQuery handle each and dislpay it where specified in my css file... for now, lets just ignore my "home" link... here is a snippet of my inline jquery $(document).ready(function() { $("a").click(function () { $("div#login").slideToggle("fast"); }); }) Now, whichever div i specify, it calls that ... however it will only call one div, using either from the un-orderd list, as mentioned above in the html. My Goal is to call a search bar when search is clicked, and to call a login box when login is clicked. to my knowledge (noob), i believe use an as a class, however that is what brings me here. i believe my error is in my jquery and not my css, as stated above, either instance will be displayed when the jquery function calls either tag. any help is greatly appreciated. thanks in advance shan2on

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  • jquery select one class from many

    - by simnom
    Hi, I'm trying to achieve the following functionality. Within a form I have multiple fields with the class name .inputField if one of these fields is selected then the div associated with that element should be shown on focus and hidden on blur. However, when I implement the code below on selecting the second element the class is applied to both. Not sure where I'm going wrong?!?!? html markup: <form class="friendlyForm" name="friendlyForm" id="friendlyForm"> <ul> <li> <label for="testField">Test field</label> <input name="testField" value="here" class="inputField" id="testField" /> <div class="helper" style="display: none;">helper text here</div> </li> <li> <label for="testField">Test field2</label> <input name="testField2" value="here" class="inputField" id="testField2" /> <div class="helper" style="display: none;">helper text here</div> </li> </ul> </form> jQuery markup: $('.friendlyForm').find('.inputField').each(function(i) { $(this).blur(); $(this).focus(function() { //Add the focus class and fadeIn the helper div $(this).parent().addClass('focus'); $(this).parent().parent().find('.helper').fadeIn(); }); $(this).blur(function () { //Remove the focus class and fadeOut helper div $(this).parent().removeClass('focus'); $(this).parent().parent().find('.helper').fadeOut(); }); }); Any pointers here would be greatly appreciated. Thanks

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  • How to format JSON Date?

    - by Mark Struzinski
    I'm taking my first crack at AJAX with jQuery. I'm getting my data onto my page, but I'm having some trouble with the JSON that is returned for Date data types. Basically, I'm getting a string back that looks like this: /Date(1224043200000)/ From a total newbie at JSON - How do I format this to a short date format? Should this be handled somewhere in the jQuery code? I've tried the jQuery.UI.datepicker plugin using $.datepicker.formatDate() wiuth no success. FYI: Here's the solution I came up with using a combination of the answers here: function getMismatch(id) { $.getJSON("Main.aspx?Callback=GetMismatch", { MismatchId: id }, function(result) { $("#AuthMerchId").text(result.AuthorizationMerchantId); $("#SttlMerchId").text(result.SettlementMerchantId); $("#CreateDate").text(formatJSONDate(Date(result.AppendDts))); $("#ExpireDate").text(formatJSONDate(Date(result.ExpiresDts))); $("#LastUpdate").text(formatJSONDate(Date(result.LastUpdateDts))); $("#LastUpdatedBy").text(result.LastUpdateNt); $("#ProcessIn").text(result.ProcessIn); } ); return false; } function formatJSONDate(jsonDate){ var newDate = dateFormat(jsonDate, "mm/dd/yyyy"); return newDate; } This solution got my object from the callback method and displayed the dates on the page properly using the date format library.

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  • jquery getscript <script> tags

    - by user1871612
    To ask about getscript html Code as follows: <!DOCTYPE html PUBLIC "- / / W3C / / DTD XHTML 1.0 Transitional / / EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html> <head> <title>jQuery GetScript</title> <script src="http://ajax.googleapis.com/ajax/libs/jquery/1.8.3/jquery.min.js"></script> <script type = "text / javascript "> $(document). ready(function () { $getScript ('script.js', function (jd) { $.each (test, function (index, value) { console.log (value); }); }); }); </script> </head> <body> <div id="dest"> </div> </body> </html> js (1) code are as follows: - <script type='text/javascript'> var test = []; test [0] = ['111 ', '222']; </ script> js (2) Code as follows: - var test = []; test [0] = ['111 ', '222']; The problem is as follows: - Run js (1) code will appear: - Uncaught SyntaxError: Unexpected token < No problem running js (2) Would like to ask how we can run js (1) can not go wrong Thank! Badly written, please forgive me.

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  • Div's are not filtered as :hidden when display:none; is appended as style

    - by CodeMonkey
    Hey folks I have some simple HTML: <div id="selectorContainer"> <div id="chainedSelector" style="display: none;"><% Html.RenderPartial("ProjectSuggest/ChainedProjectSelector"); %></div> <div id="suggestSelector"><% Html.RenderPartial("ProjectSuggest/SuggestControl", new SuggestModeDTO{RegistrationMode = Model.RegistrationMode}); %></div> </div> which is two containers for controls. I have jQuery code to toggle between displaying these, but I need to store as a cookie which one was used last time the user was logged in (i.e. which one was visible). The storing of the cookie is not the problem. The problem is that I for some reason am not able to detect which one is the hidden one, using .is(":hidden"), and not able to detect which one is visible using .is(":visible") When I use those two selectors, I always get both. "true" and "true" for both, eventhough one has display: none; and the other doesn't. Please note that they are NOT placed inside a hidden container which otherwise would hide both, so there are not any hidden ancestor containers. Can anyone maybe explain why this could happen? jQuery code containing source for getting the Id's and for getting the selected one (which currently is broken): getChainedSelectorId: function() { return "#chainedSelector"; }, getSuggestSelectorId: function() { return "#suggestSelector"; }, getSelectedSelector: function() { alert($(this.getChainedSelectorId()).is(":hidden")); alert($(this.getSuggestSelectorId()).is(":hidden")); var selected = ($(this.getChainedSelectorId()).is(":visible") ? this.getChainedSelectorId() : this.getSuggestSelectorId()); alert(selected); return selected; }, Thanks in advance.

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  • jQuery Drill down selector ?

    - by Etienne
    Hi, I have made this piece of code that makes a roll hover effect on any image you add the class 'simplehover' to it : //rollover effect on links $(".simplehover").mouseover(function () { $(this).attr("src", $(this).attr("src").replace("-off.", "-on.")); }).mouseout(function () { $(this).attr("src", $(this).attr("src").replace("-on.", "-off.")); }); <img src="slogan.gif" class="simplehover" /> Im trying to get it work if you add the class 'simplehover' to the surrounding element : . (especially usefull for ASP.net asp:HyperLink tag which automatically generate the IMG tag inside the hyperlink. <a href="#" class="simplehover"> <img src="slogan.gif" /> </a> If I change my selector for : $(".simplehover img") , it will work, however it no longer works in senario #1. I tried this with no luck: $(".simplehover").mouseover(function () { if ($(this).has('img')) { $(this) = $(this).children(); } ... Anyone can figure this out?

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  • jQuery .height() property not working

    - by Andrew
    I'm attempting to get the height of an element using jQuery, but am receiving some unexpected results. Here's the code: $(function() { var contentheight = $('#subpage-content-small').height; alert(contentheight); }); Where #subpage-content-small has these CSS properties: #subpage-content-small { width: 400px; float: left; margin: 30px 10px 0 0; padding-bottom: 45px; } What I'm getting as an output for my alert is the following: function (f) { var e = this[0]; if (!e) { return f == null ? null : this; } if (c.isFunction(f)) { return this.each(function (j) {var i = c(this);i[d](f.call(this, j, i[d]()));}); } return "scrollTo" in e && e.document ? e.document.compatMode === "CSS1Compat" && e.document.documentElement["client" + b] || e.document.body["client" + b] : e.nodeType === 9 ? Math.max(e.documentElement["client" + b], e.body["scroll" + b], e.documentElement["scroll" + b], e.body["offset" + b], e.documentElement["offset" + b]) : f === w ? c.css(e, d) : this.css(d, typeof f === "string" ? f : f + "px"); } Any idea why I'm getting this as opposed to an integer of the height? Thanks in advance!

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  • Why is this ajax call being made even though it shouldn't be

    - by user2921557
    i have this validation script im working on but cant see why im having an issue. You can see that i have a check = false / true, check before it runs the ajax call. However, even if a field is empty and check is set to false, it is still running the call. so: // JavaScript - Update Password AJAX $(document).ready(function () { // When the form is submitted $('.updatepasswordform').submit(function () { var check = true; // Get the values var password1 = $("input[name=password1]").val(); var password2 = $("input[name=password2]").val(); var newpassword = $("input[name=newpassword]").val(); /* Password Validation */ // If fields are empty if (password1 === '') { check = false; $("input[name=password1]").css('border', 'solid 2px red'); } // If fields are empty if (password2 === '') { check = false; $("input[name=password2]").css('border', 'solid 2px red'); } // If fields are empty if (newpassword === '') { check = false; $("input[name=newpassword]").css('border', 'solid 2px red'); } if (check = true) { $.ajax({ type: "POST", url: "process/updatepassword.php", data: $(".updatepasswordform").serialize(), dataType: "json", success: function (response) { /* Checks for database validation, removed for space saving */ } }); } return false; }); });

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  • How do I access a <form> that is not the master page <form>?

    - by VBCSharp
    Winforms developer converting to web developer. I know the part about the Master Page having the tag, what is not clear is if I can or can not have another in one of my content pages. I have been seeing both answers doing searches. I see yes you can if only one has runat=server. The thing is I have a that contains several radio buttons on a web page that has a master page. I have a .js file that has a function if I send the name into it, it will loop thru the controls in the form to see which one is selected and return the desired date horizon(MTD, QTD, YTD, etc.). When I run this on a non master page web page it works fine. However, when I run on a web page that has a master page I can't seem to get to the element. I tried getElementByID, I tried looping through the page elements, etc. Maybe I am going about this incorrectly and I hope someone can straighten me out. Here is the code from my .js file that may help explain what I am trying to do a little better. var frmDateRanges = document.getElementById(formFieldName); var chosen; var len = frmDateRanges.DateRanges.length; for(i=0;i<len;i++) { if(frmDateRanges.DateRanges[i].checked) { chosen = frmDateRanges.DateRanges[i].value; } } where formFieldName is an arguement that is passed into the function and DateRanges is the name value given to the radio buttons. In the button I call this function I have: onclick ="FunctionCall('frmDateRanges')" FunctionCall is just for description purposes, 'frmDateRanges' is the name and id given to the form action="" Thanks for the help as I am stumped at this point. If there is a better way to do this please let me know that as well.

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  • Select hidden input from within next td [jQuery]

    - by Fverswijver
    I have a table layed out like this: <td> somename </td> <td class="hoverable value" > somevalue </td> <td class="changed"> </td> <td class="original value"> <input type="hidden" value="somevalue" /> </td> And what I'm trying to do is, I hover over the hoverable td which turns it into a textbox. Once I hover out I want to check the hidden field for it's original value and put an image in changed if the 2 are different from each other. I already have this: $(document).ready( function() { var newHTML = ''; $('table td.hoverable').hover( function () { var oldHTML = $(this).html().trim(); $(this).html('<input type=\'text\' value=\'' + oldHTML + '\' size=\'' + ((oldHTML).length + 2) +'\' />'); }, function() { newHTML = $('input', this).val(); var oldHTML = $(this).next('td.original').children('hidden').val(); if(newHTML != oldHTML) { $(this).next('td.changed').html('Changed'); } $(this).html(newHTML); }) }); but it doesn't work. What fails apparently is grabbing the value of the hidden field, and I've tried selecting it in several different ways but just can't get to it. Any ideas or tips are gratefully appreciated ;)

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  • change images by clicking left and right

    - by Qin
    I want to display an image in the center of the page, then 2 buttons, left, and right, when I click on left, the image changes to previous one, and move to next image by clicking right. And my question is, the code doesn't work..=.=, very obvious, can anybody tell me where the mistakes are? <table id="frontpage"> <tr> <td><input type="button" id="left" value="left"/></td> <td><img id="image" alt="Image" src="./image/guildwars2/gw2_fight.jpg"/></td> <td><input type="button" id="right" value="right"/></td> </tr> </table> $(document).ready(function(){ var image=new Array(); var current=0; image[0]=new Image(); image[0].src="./image/guildwars2/gw2_fight.jpg"; image[1]=new Image(); image[1].src="./image/diablo3/d3.jpg"; image[2]=new Image(); image[2].src="./image/dota2/catOnWater.jpg"; $("#left").click(function(){ if(current-1<0){ current=image.length-1; $("#image").attr("src")=image[current].src; } else{ --current; $("#image").attr("src")=image[current].src; } }); $("#right").click(function(){ if(current+1>image.length-1){ current=0; $("#image").attr("src")=image[current].src; } else{ ++current; $("#image").attr("src")=image[current].src; } }); })

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  • Want to convert whole PHP script in RUBY ON RAILS

    - by user303058
    // set image quality (from 0 to 100, not applicable to gif) $imgquality = 100; // get data from $_POST or $_GET ? $data = &$_POST; // get image dimensions $width = (int) $data['width']; $height = (int) $data['height']; // create image object $img = imagecreatetruecolor($width, $height); // populate image with pixels for ($y = 0; $y < $height; $y++) { // innitialize $x = 0; // get row data $row = explode(',', $data['r'.$y]); // place row pixels $cnt = sizeof($row); for ($r = 0; $r < $cnt; $r++) { // get pixel(s) data $pixel = explode(':', $row[$r]); // get color $pixel[0] = str_pad($pixel[0], 6, '0', STR_PAD_LEFT); $cr = hexdec(substr($pixel[0], 0, 2)); $cg = hexdec(substr($pixel[0], 2, 2)); $cb = hexdec(substr($pixel[0], 4, 2)); // allocate color $color = imagecolorallocate($img, $cr, $cg, $cb); // place repeating pixels $repeat = isset($pixel[1]) ? (int) $pixel[1] : 1; for ($c = 0; $c < $repeat; $c++) { // place pixel imagesetpixel($img, $x, $y, $color); // iterate column $x++; } } } // set proper content type header('Content-type: image/'.$imgtype); header('Content-Disposition: attachment; filename="chart.'.$imgtype.'"'); // stream image $function = 'image'.$imgtype; if ($imgtype == 'gif') { $function($img); } else { $function($img, null, $imgquality); } // destroy imagedestroy($img); ?

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  • Youtube Javascript API play(); not working.. what am I doing wrong?

    - by odpogn
    Hello, I'm playing around with YouTubes Javascript API. I've set up a test page on my local enviornment, but the play function is not working. The video loads, and I can press play on the yt video screen, but my link "play" isn't working. Can someone tell me what I'm doing wrong?? I've been following this: http://code.google.com/apis/youtube/js_api_reference.html <html> <head> <script type="text/javascript" src="public/javascripts/swfobject.js"></script> </head> <body> <div id="ytapiplayer"> You will need Flash 8 or better to view this content. </div> <script type="text/javascript"> var params = { allowScriptAccess: "always" }; var atts = { id: "myytplayer" }; swfobject.embedSWF("http://www.youtube.com/v/OQSNhk5ICTI&enablejsapi=1&playerapiid=ytplayer", "ytapiplayer", "425", "365", "8", null, null, params, atts); function onYouTubePlayerReady(playerId) { ytplayer = document.getElementById("myytplayer"); } function play() { if (ytplayer) { ytplayer.playVideo(); } } </script> <a href="javascript:void(0);" onclick="play();">Play</a> </body> </html>

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  • I just wanted to DES 4096 bytes of data with a 128 bits key...

    - by badp
    ...and what the nice folks at OpenSSL gratiously provide me with is this. :) Now, since you shouldn't be guessing when using cryptography, I come here for confirmation: what is the function call I want to use? What I understood A 128 bits key is 16 byte large, so I'll need double DES (2 × 8 byte). This leaves me with only a few function calls: void DES_ede2_cfb64_encrypt(const unsigned char *in, unsigned char *out, long length, DES_key_schedule *ks1, DES_key_schedule *ks2, DES_cblock *ivec, int *num, int enc); void DES_ede2_cbc_encrypt(const unsigned char *input, unsigned char *output, long length, DES_key_schedule *ks1, DES_key_schedule *ks2, DES_cblock *ivec, int enc); void DES_ede2_cfb64_encrypt(const unsigned char *in, unsigned char *out, long length, DES_key_schedule *ks1, DES_key_schedule *ks2, DES_cblock *ivec, int *num, int enc); void DES_ede2_ofb64_encrypt(const unsigned char *in, unsigned char *out, long length, DES_key_schedule *ks1, DES_key_schedule *ks2, DES_cblock *ivec, int *num); In this case, I guess the function I want to call DES_ede2_cfb64_encrypt, although I'm not so sure -- I definitely don't need padding here and I'd have to care about what ivec and num are, and how I want to generate them... What am I missing?

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  • Jquery Resize Line of text To Fit Div Width

    - by Douglas Cottrell
    I am using the following script to resize a one line string to fit properly in a div box. <script type="text/javascript"> $( '.test' ).css( 'font-size', 0 ).each(function ( i, box2 ) { var width = $( box2 ).width(), line = $( box2 ).wrapInner( '<span style="white-space:nowrap">' ).children()[ 0 ]; function changeFontSize( n ) { $( box2 ).css( 'font-size', function ( i, val ) { return parseInt( val, 10 ) + n; }); } while ( $( line ).width() < width ) { changeFontSize( 1 ); } changeFontSize( -1 ); $( box2 ).text( $( line ).text() ); }); </script> This script works perfect in FF, Chrome, and opera. However in IE if the user is in compatability mode it errors and locks up the browser. I do not know enough about the older browsers to know what I have added that is not compatible. Any help is greatly appreciated.

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  • possible to make codeigniter work with another framework?

    - by ajsie
    the situation is this. my client (who also is a programmer) asks me to develop an address book (with mysql database) with a lot of functions. then he can interact with some class methods i provide for him. kinda like an API. the situation is that the address book application is getting bigger and bigger, and i feel like its way better to use CodeIgniter to code it with MVC. i wonder if i can use codeigniter, then in some way give him the access to controller methods. eg. in a controller there are some functions u can call with the web browser. public function create_contact($information) {..} public function delete_contact($id) {..} public function get_contact($id) {..} however, these are just callable from web browser. how can i let my client have access to these functions like an API? then in his own application he can use: $result = $address_book-create_contact($information); if($result) { echo "Success"; } $contact = $address_book-get_contact($id); is this possible? cause i just know how to access the controller methods with the webbrowser. and i guess its not an option for him to use header(location) to access them. all suggestions to make this possible are welcomed! thanks

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  • .NET remoting: System references wrong .NET dll, but how to cure ?

    - by Quandary
    Question: I defined an interface like below. The problem now is, that when I add the dll (API.dll) as reference in an asp.net project, it references a wrong API.dll, though I referenced the correct dll. In turn, it doesn't find GetLDAPlookup, but there is another method that is not in defined here, but in an older version of API.dll... I rebuilt the dll I referenced, so it is definitely the latest version that I added as reference. Do I have to add another GUID, or something ? Imports System.Runtime.InteropServices Namespace RemoteObject ''' <summary> ''' Defines server interface which will be deployed on every client ''' </summary> ''' <GuidAttribute("921DE547-32FA-40BB-961A-EA390B7AE27D")> _ Public Interface IServerMethods ''' <summary> ''' Function to call the server from the client ''' </summary> ''' <param name="strMessage">Some text</param> ''' Sub ServerPrint(ByVal strMessage As String) ''' <summary> ''' Function to call the server from the client ''' </summary> ''' <param name="strMessage">Some text</param> ''' <returns>Some interesting text</returns> ''' Function GetLDAPlookup(ByVal strMessage As String) As System.Data.DataSet End Interface End Namespace

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  • how to get the values dynamically in js

    - by jeessy
    hi having problem with my id iam making my website for health product. already we have a 10 products with corresponding amounts in this section customer choose the product through drop down box. in next we are getting service charges from customer by clicking radio buttons. we have a three radio buttons with name=add and three amount value like 5$ 7$ 9$. It is working fine. for example: customer selected 3 produts in the sense that total amount around 20$ after customer clicks this radio button(any) and submit button that amount will add with totally in next page ie 25$ what i want is that radio button amount should add with get payment then display the page dynamically. function checkRadio (frmName, rbGroupName) { var radios = document[frmName].elements[rbGroupName]; for (var i=0; i < radios.length; i++) { if(radios[i].checked) { return true; } } return false; } $(document).ready(function(){ $("input[name='rmr']").click(function() { updatePayment($(this).val()); if (!!$(this).attr("checked") == true) { $("#finalamount").html( parseInt($("#totalamount").val(), 10) * parseInt($(this).val(), 10)); } }); } this code is right or wrong. thanks in adv

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  • in haskell, why do I need to specify type constraints, why can't the compiler figure them out?

    - by Steve
    Consider the function, add a b = a + b This works: *Main> add 1 2 3 However, if I add a type signature specifying that I want to add things of the same type: add :: a -> a -> a add a b = a + b I get an error: test.hs:3:10: Could not deduce (Num a) from the context () arising from a use of `+' at test.hs:3:10-14 Possible fix: add (Num a) to the context of the type signature for `add' In the expression: a + b In the definition of `add': add a b = a + b So GHC clearly can deduce that I need the Num type constraint, since it just told me: add :: Num a => a -> a -> a add a b = a + b Works. Why does GHC require me to add the type constraint? If I'm doing generic programming, why can't it just work for anything that knows how to use the + operator? In C++ template programming, you can do this easily: #include <string> #include <cstdio> using namespace std; template<typename T> T add(T a, T b) { return a + b; } int main() { printf("%d, %f, %s\n", add(1, 2), add(1.0, 3.4), add(string("foo"), string("bar")).c_str()); return 0; } The compiler figures out the types of the arguments to add and generates a version of the function for that type. There seems to be a fundamental difference in Haskell's approach, can you describe it, and discuss the trade-offs? It seems to me like it would be resolved if GHC simply filled in the type constraint for me, since it obviously decided it was needed. Still, why the type constraint at all? Why not just compile successfully as long as the function is only used in a valid context where the arguments are in Num? Thank you.

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  • PHP: exif_imagetype() not working?

    - by Karem
    I have this extension checker: $upload_name = "file"; $max_file_size_in_bytes = 8388608; $extension_whitelist = array("jpg", "gif", "png", "jpeg"); /* checking extensions */ $path_info = pathinfo($_FILES[$upload_name]['name']); $file_extension = $path_info["extension"]; $is_valid_extension = false; foreach ($extension_whitelist as $extension) { if (strcasecmp($file_extension, $extension) == 0) { $is_valid_extension = true; break; } } if (!$is_valid_extension) { echo "{"; echo "error: 'ext not allowed!'\n"; echo "}"; exit(0); } And then i added this: if (exif_imagetype($_FILES[$upload_name]['name']) != IMAGETYPE_GIF OR exif_imagetype($_FILES[$upload_name]['name']) != IMAGETYPE_JPEG OR exif_imagetype($_FILES[$upload_name]['name']) != IMAGETYPE_PNG) { echo "{"; echo "error: 'This is no photo..'\n"; echo "}"; exit(0); } As soon when I added this to my imageupload function, the function stops working. I dont get any errors, not even the one i made myself "this is no photo", what could be wrong? Just checked with my host. They support the function exif_imagetype()

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  • next previous button in div jquery mobile

    - by satine kianne
    i have a total of 11 div in my app. what i want to do is to display 3 divs in between 2 permanent div it should look like this |first permanent div| |div 1| |div 2| |div 3| |second permanent div| |previous| |next| when i click on next is should look like this |first permanent div| |div 2| |div 3| |div 4| |second permanent div| |previous| |next| and so on. and when im not div 1,2,3 the previous should be disabled and when im no 7,8,9 the next should be disabled. but i cant make it i'm using this fiddle as a sample http://jsfiddle.net/WGkPV/1/ its working but only one div is shown in the center of my two permanent div which is not in my plan.im getting like this |first permanent div| |div 1| |second permanent div| |previous| |next| any suggestion will be taken seriously. here is the code of the fiddle im working on as tutorial $(document).ready(function () { var divs = $('.mydivs>div'); var now = 0; // currently shown div divs.hide().first().show(); $("button[name=next]").click(function (e) { divs.eq(now).hide(); now = (now + 1 < divs.length) ? now + 1 : 0; divs.eq(now).show(); // show next }); $("button[name=prev]").click(function (e) { divs.eq(now).hide(); now = (now > 0) ? now - 1 : divs.length - 1; divs.eq(now).show(); // or .css('display','block'); //console.log(divs.length, now); }); }); <div class="mydivs"> <div>div 1</div> <div>div 2</div> <div>div 3</div> <div>div 4</div> </div>

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  • Fade in an HTML element with raw javascript over 500 miliseconds.

    - by Juan C. Rois
    Hello everybody, Once again I find myself stuck by something that I just don't understand. Any help would be appreciated. I'm working on a modal window, you click something and the background is masked and a modal window shows some content. I have a div with "display:none" and "opacity:0", and when the user triggers the modal, this div will overlay everything and have certain transparency to it. In my mind, what I need to do is: Set the opacity Perform a "for" loop that will check if the opacity is less than the desired value. Inside this loop, perform a "setInterval" to gradually increment the value of the opacity until it reaches the desired value. When the desired value has been reached, perform an "if" statement to "clearInterval". My code so far is as follows: var showMask = document.getElementById('mask'); function fireModal(){ showMask.style.opacity = 0; showMask.style.display = 'block'; var getCurrentOpacity = showMask.style.opacity; var increaseOpacity = 0.02; var finalOpacity = 0.7; var intervalIncrement = 20; var timeLapse = 500; function fadeIn(){ for(var i = getCurrentOpacity; i < finalOpacity; i++){ setInterval(function(){ showMask.style.opacity = i; }, intervalIncrement) } if(getCurrentOpacity == finalOpacity){ clearInterval(); } } fadeIn(); } As you all can guess, this is not working, all it does is set the opacity to "1" without gradually fade it in. Thanks in advance for your help.

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