I'm wondering if it's possible to make a download counter without the use of php. I have been told it's possible but cannot find anywhere that has helped me.
I am trying to save the counts to text file on the server. I cannot use php as my server does not allow the use of it. I have tried javascript but can't seem to get anything working. Any suggestions or guidance would be appreciated!
The server allows, html, javascript, and css.
PHP is the most common server language available on hosting services, if your server does not allow it, it's possible you can't use any language at all on the server side.
Let's assume you can't use any language on the server side, then there is two possible actions.
use a third party server where you can save your data.
save locally your data using javascript.
Using a 3rd party service might be complex to implement and you need to learn a bit about cross origin request. You will need to add a few javascript librairies and understand a lots of concept so I'll just go with the easy one.
You browser have a localStorage wich can be access through Javascrip
https://developer.mozilla.org/en-US/docs/Web/API/Window/localStorage
[!] Know that this will be save only on your browser therefore other users or session will not have access to the counter.
// get the saved value or zero if not found
var count = localStorage.getItem('so-demo') || 0;
// increment the value by 1
count++;
// save the value
localStorage.setItem('so-demo', count);
// show the actual value
document.getElementById('theValue').innerHTML = count
<div id="theValue">localStorage is not allowed on stack overflow but works elsewhere</div>
The similar question had already been raised, check out this topic
The way suggested with Google Analytics out there is quite a good idea
Related
Hey I have been looking around for like 2 hours now and cant really find what I'm looking for. I want to turn a JavaScript variable into a server-side variable so that when it is changed it is changed for everyone visiting the site. I have tried looking at Node JS, XML, PHP and SQL but i have absolutely no clue which one is the one I need to do this. If any of you guys could give me something to research in order to accomplish this I would be grateful.
My code is a voting function that just increments a variable by 1 and I want it to stay as that variable when refreshed and visited by others.
JS:
/*global*/ buttonText = "Global Clicks: 0";
/*global*/ amountOfvotes = 0;
function addVote() {
var newButtonText = buttonText.replace("0", amountOfvotes++);
document.getElementById('global-respects').innerHTML = newButtonText;
}
Thanks!
There are a lot of solutions that you can use for your problem. The first two things which are in my mind are a (1) classic client-server communication, and (2) the usage of web sockets. Well, I am not so firm in the usage of web sockets, so I describe the "easier" client-server communication.
An information before I start: The tools and programming languages are mostly independent. However, you can use JavaScript on the client and PHP on the server side for example.
The first, you need, is a (e.g. JavaScript) variable on your client. You had called it amountOfVotes (cf. the picture at the end). There are two things happen during the client is active: (1) if the client add a vote it has to send it to the server; (2) all clients have to stay up-to-date.
If the Add Vote button is clicked, then you send a message (e.g. via Ajax) to your server application. Then, the server takes its current amountOfVotes, adds one vote, and stores it (e.g., in a file or mysql database).
Your clients need an intervalled function. This function sends (e.g., via Ajax) a message to the server to get the current amountOfVotes. The server's responds with the current number and the client is up-to-date.
how to found how many times a news(for example)are read in website?
<p> <!-- my news--></p>
var counter=0;
windows.onload=function() {
counter++;
}
You can't use a JavaScript variable to hold your counter. Each time your page loads this variable is reset to 0.
You need to store the information somewhere, such as a database or in a file on the server. You can't store information like this inside your code.
Look into MySQL databases and PHP.
Your own server's logs can tell you how many times a page has been loaded, and that's a far easier approach than using JavaScript. If you absolutely have to use JavaScript, you'll need to use Ajax (or something) to communicate the result to the server.
Really, Google Analytics is the right tool for this job.
Ok here's my problem. I'm working on this little site called 10winstreak and I'm trying to detect if a stream is live or not with javascript because our server that we run the site off of cant handle processing every single request with PHP. The basis of detecting if a stream is live or not is you go to their XML file and in one of their tags (if it's live) it will say something along the lines of true and often time the XML file on their site will be empty if a particular stream isn't live. for example if you have a twitch.tv stream for gamespot you go to http://api.justin.tv/api/stream/list.xml?channel=gamespot and if it's got stuff in it then it's live if not then it's not.
so basically my code looks like this:
function check (URL, term){
$.get(URL , function(data){
console.log(data);
//data is whatever the server returns from the request, do whatever is needed with it to show who is live.
var number = data.search(term);
if (number > -1)
{
document.write("Live");
}
else
{
document.write("Offline");
}
});
}
and URL is a url that gets passed in and term is the term to search for in the xml file (usually "true" or "True"). but before anything happens I end up with "XMLHttpRequest cannot load http://api.own3d.tv/liveCheck.php?live_id=6815. Origin (my server's URL) is not allowed by Access-Control-Allow-Origin."
I've looked into it all over the net and i dont seem to be able to find anything that I can use. there's alot of theory stuff but not enough actual code and i dont understand the theory stuff to be able to start typing code out. from what i've seen you have 2 ways to go, use JSONP or add a line somewhere in your sever to allow for cross-domain accessing. neither of which i understand fully nor know how or what to do. It would be alot of help for someone to show me what needs to be done to get rid of this error. of course if you can explain it to a non-coder like me it would be even more awesome but at my current point, as long as the code works for all I care it might as well be magic lol.
You can solve it :)
Take a look at xReader
<script src="http://kincrew.github.com/xReader/xReader.full.js"></script>
<script type="text/javascript">
xReader("http://api.own3d.tv/liveCheck.php?live_id=6815", function(data) {
alert(data.content);
})
</script>
I think you need cacheburst option. but you can be banned from YQL.
I think its because the path is not relative. You may be calling this from a different domain/sub-domain. You can potentially allow other origins to access, which may open up a security hole or you can create a proxy locally.
In PHP creating a proxy is easy: http://blog.proxybonanza.com/programming/php-curl-with-proxy/
Now, instead of directing your request straight to that URL send the request from jQuery to your own local url and have it access it on the server side.
Another option would be to use YQL: http://www.parrisstudios.com/?p=333 (I wrote an article about this a while ago)... In that way you can turn the response into JSON, which can be accessed cross-domain (as can javascript).
You could ask for the API responses to all be returned using a JSONP server and in JSON.
You aren't going to be able to do this via client-side javascript unless they've enabled some way to retrieve their data cross-domain (CORS, JSONP, some flash widgety thing getting read permissions from crossdomain.xml file(s) located on their server...)
Short answer: unless 10winstreak offers a JSONP service, you'll have to do things on the server-side.
Slightly longer answer:
For security reasons browsers won't let you make AJAX requests from www.example.com to www.example2.com (or any other domain except www.example.com). There isn't much you can do about this except use JSONP (and you can only do that if the remote webservice offers it).
Therefore, what you end up needing to do is ask your server "hey what's on that other server?" and (since it's not limited the way a browser is) it can go get the XML from that other server. There are various ways of doing this, either with code or Apache config; not sure what's right for you, but hopefully now you understand the general principle.
P.S. See this question: Wouldn't have been simpler to just discard cookies for cross-domain XHR? if you are curious why browsers do this.
* EDIT *
I just checked out JustinTV's site, and it appears that they already have a PHP library for you to use:
https://github.com/jtvapi/jtv_php_api
This is very likely your best bet (if you want to keep using PHP that is; if not they have libraries for other languages: http://www.justin.tv/p/api).
Our system using HttpContext.Current.Session("Client") to store the current user info.
One property in the session is a roleID i.e. CType(HttpContext.Current.Session("Client"), Client).RoleId
By checking the value of RoleId, the system can identify whether the user can access a couple of pages.
I've validated it in the server-side. But for the easiest way to present the Notice Message I think is using JavaScript.
So is it possible to get the session value in JavaScript (even in a external JavaScript)?
How about Cookie? What is the drawback for adding Cookies for an existing system?
And any other suggestions if you have.
Thx
Yes, I did the validation in server side. Later again, I'll add restrictions in DBs as well.
Result:
I used webMethod inside a web service, caz it is a Master Page.
Thanks for you answer.
but another issue raised:
Trigger/Prevent page event by using asynchronous webmethod return value in JavaScript
please give me some advise on that question as well, thx.
You could do it as a cookie, but it would slow down your round trip for every resource. Hence, I don't recommend this approach.
One option is to have a dynamic page that returns a javascript object in global with the appropriate variables printed out. You then could just include it as a standard script tag.
Another approach is to make an AJAX call.
Keep in mind, you should still always validate the base request and never trust the client.
Sending roles to the client and using JavaScript for business logic based upon these roles is a security risk. Users (hackers) know how to manipulate client-side code to gain access to things they're not supposed to.
I recommend sending down only the content the user has access to or use AJAX to retrieve the content dynamically from the client.
But to answer your question, no, you cannot retrieve session data directly from the client.
You can make ashx page or WCF service and call that with javascript. But don't return roleID and check that ID on client, instead just return true / false if user has access. Use jQuery ajax call to ashx or WCF service, you should find tons of examples on google
I am setting up a quiz that uses boolean variables for correct/incorrect and then passes those variable values to a PHP script via Ajax for processing and storing in a database.
How easily could someone override the values set by my code with after finding the var names with "view source"?
Yes.
You should send the answers to the server and let the server grade the quiz.
They can do it easily using Chrome/Firebug Console by issuing a Javascript command over there like
var your_var_name = 60;
You must have backend synchronization also to prevent this.
for testing purpose you can use firefox add on firebug or chrome's developer tool kit. Change your javascript variable using inspect element and than perform action of button which posts your data. On server side you should make sure that posted variable must be any of variable that is in option of answer of that question.