how to fetch post() method parameter through javascript? - javascript

i'm working on mobile development and developing pure JavaScript, CSS and HTML code, cant use any server side scripting like PHP, Jsp n all since i have to feed it in phone-gap. I just want to know how i can fetch the post parameters through JavaScript(like in jsp we fetch it through request.getparameter) ? please help me out guys thanks in advance.

There is no way to read POST data from the request that generated the current page using client side JavaScript.

In my mind you have the change the way your app will work. But if you really want to send your form on a page, you can use GET method and retreive parameters from the URL
http://css-tricks.com/snippets/jquery/get-query-params-object/
The normal way : on form submit you should have a JS function, and this function has to do the job.
Do not forget to use Google/Stackoverflow.com you should find your answer ;-)
How do you post a form in Phonegap?

Related

POST value to cgi file but not update the web page

I have a web page with a switch (html & CSS) and a toggle function (JS) which changes the appearance of the switch as it is clicked. The toggle function has a 'standby' variable which tracks the status of the switch.
I also have a form (JS) which POSTs the value of standby to a cgi script (python) which will control some lights. That all works!
Except, I do not want the cgi file to respond with a new web page or even reload the current web page - I'd like to keep the page as it is - which does not seem possible with cgi!
I'm guessing cgi is the wrong approach (& this is another dumb question!)
Thanks in advance...
You can send your Form using Ajax. The easiest way is to use Jquery.
Here is a nice tutorial:
http://hayageek.com/jquery-ajax-form-submit/
You’ll need to make your request asynchronously using JavaScript.
Have a look at the XMLHttpRequest object or use a wrapper function like jQuery’s $.ajax method (especially if you want to support older browsers).
Please see this answer for an example of how to do a POST request using the XMLHttpRequest object.
Thanks for all the answers - I appreciate you putting me on the right track. I used JQuery and ajax as suggested and it is working - simple when you know how!
This is in index.html:
$.ajax({
type: "POST",
url: "/cgi-bin/standby.py",
data: {status: standby}
});
and in standby.py:
data = cgi.FieldStorage()
data = data["status"].value

Using JavaScript to send String to Servlet, and Results from servlet back to JavaScript

First of all: sorry for my bad grammer. English isn't my native language, but i will try to exlpain my problem as simple as i can.
I'm working on a web-application, where user can enter a link. (Question 1) This link should be send to the server/servlet and will be progressed to other things. (Question 2) After the progression, the servlet will send a json-array (?) back to the javascript-part of my app.
I'm completly new to this kind of stuff, but its very important to me, to find out how this works or better, how i can make this work. Its actually very simple, but i used plenty of weeks and cant figure it out.
The application is using the SAP UI5-libs (Question 3), where i would also like to know, if there is any possible way, to parse JSON with the UI5 libs.
I hope, i could explain my problem good enough, so i can get some help. Thanks to all!
The 'sending' of the string to the server/servlet would happen via ajax in either POST or GET form. That is up to you.
I recommend you use a javascript plugin like jQuery (JQuery Ajax API) because the regular ajax code is a bit messy.
As for the servlet/server communicating back to the client is as simple as writing to the page. In a typical servlet context it would be something like
out.print("This is a message");
where Ajax automatically returns the content of the entire page upon callback.
So in conclusion:
Consider test.jsp your servlet. I wish to send "Hi" from the client (being the browser) via GET to the servlet and I want the servlet to say "Hello" back.
I would open an ajax request of type GET to the url "test.jsp?param=Hi". In the servlet I receive this page request and process it. The servlet discards the parameter because it is not used and outputs "Hello" to the page.
In the client the ajax will have returned "Hello" and I can use this to put it into a var or whatever and all of this happened while not refreshing and not navigating in the original document where I did the javascript.
Another way is using websockets where you basically use sockets in javascript to send and receive any kind of data.
Also please check out this possible duplicate question: How to send a string to a servlet from javascript using xmlhttprequest

jQuery send values through POST

I'm trying to implement a third party tool. This tool uses a form with the post method to send data to their site. Is there any way that I can mimic this action without using the form tag? I don't know much about jquery post and same domain (this is sending it off to a different domain) so I don't know if there would be an issue with this.
Everything that I've found in my search talks about ajax and returning content after you post but all I want to do is to take the customer to the third party's site after they have submitted the form.
thanks!
You cannot send data to a different domain with AJAX. Its not permitted by the browser. As for can you do it without a form element, yes. Just encode the data as it would look in a browser get URL like http://site.com/search?query=I+love+js&perpage=10&page=2
datatosend="field1="+value+"&field2="+value2
$.post(url,datatosend,function(data){//do something with data. location.href="new location"}
Yes you can.
Check out this post.
https://stackoverflow.com/a/1078991
also found in the docs
http://api.jquery.com/jQuery.post/
http://api.jquery.com/jQuery.post/
and then you can do a location.replace() when it is completed
function replaceDoc()
{
window.location.replace("http://www.thatsite.com")
}

Use hidden iframe to submit data

I need to submit some information to my servlet. Once I submit this information, I'll receive a PDF from the servlet based on the data. I know I can construct the URL and pass parameters to it using HTTP GET. Suppose my form data is too large.So is it possible to do this using a hidden iFrame? I'll submit the parameters using the hidden iFrame and in my servlet, I write the PDF to the response stream. Will this work? If it works can someone please suggest me how to do this?
You'll need to set the target to the iframe you want to submit it to.
<form action='...' name='theform' target='theiframe'>
.
.
.
<iframe name='theiframe' src='...'>
</iframe>
</form>
This forum post has some details : http://forums.powweb.com/showthread.php?t=77213
Hm, which way do you want to sent the data using your iframe? I think you're limited to either GET or POST there, too. Means, if your data is too large, the iframe won't help sending your data.
What server backend do you use? You might be able to configure the maximum size of request data (post / get).
Please have a look at this message for more information about this.
In my eyes, using the hidden Iframe method is very old school, almost like before the great days of Ajax methods.
You can use jquery Ajax call and serialize your full form passing all variables. Remember to check your request size in your config, in case it post reaches maximum size.

Post raw form data from web page

I would like to send raw post data using straightforward DHTML, but without using the XMLHttpRequest object. Is this possible to do this, for example, by forcing an HTML form element's post data to an arbitrary string?
Before you post the form, you could dynamically add html input elements (with values) to the form, and then call form.sumbit(). This will still refresh the page though.
The only way that I'm aware of to post data without refreshing the page is using the XMLHttpRequest object. Using jQuery makes this whole operation pretty trivial http://api.jquery.com/jQuery.post/ , so I'm not sure why you don't want to use ajax to accomplish this?
You can easily generate a string that resembles a POST request. There is not much difference between a POST and a GET. Using GET, the parameters are added behind the url. When POSTing, the parameters are added in the same way, but below the headers.
See developers.sun.com for an example.

Categories