Re: [PHP] php - js (was Javascript Navigation)
On Thu, April 27, 2006 6:39 pm, tedd wrote: At 1:57 PM -0700 4/27/06, Paul Novitski wrote: variable to js and will cause js to execute. But, isn't there anything else? Is that all there is? That's all there is unless you really want to chew up all your HTTP connctions with a hell of a lot of useless information going back-and-forth... You could get an ongoing dialog going with PHP and JS as you have done with AJAX, and you could even get the two of them to send each other specific messages you would make up that would make the other one poll back for more info... But that would be incredibly wasteful. If you need that kind of real-time client-server interaction, you should: A) Switch to Java which kinda sorta has a working keep-alive applet/servelet model. B) Write a custom client-server application. But trying to force JS - PHP communication the way you are describing it is only going to make you very unhappy in the long run. -- Like Music? http://l-i-e.com/artists.htm -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] php - js (was Javascript Navigation)
At 4:54 AM -0500 4/29/06, Richard Lynch wrote: But trying to force JS - PHP communication the way you are describing it is only going to make you very unhappy in the long run. Been to that dance more than once. But, as Dirty Harry once said A man's got to know his limitations. Thanks for all your help -- you guys have been super. tedd -- http://sperling.com -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] php - js (was Javascript Navigation)
At 5:54 PM -0700 4/27/06, Paul Novitski wrote: At 04:39 PM 4/27/2006, tedd wrote: What I don't get is how php can pass variables to js and cause it to run at will. Do you mean the way one function can call another function within the same program? No, I realize that php are two different language on two different computers sharing one event. It sounds like you're picturing PHP JavaScript executing continuously simultaneously. You aren't, are you? Not simultaneously and/or continuously but an easy way to communicate with each other. JavaScript can execute a PHP program at will simply by requesting a PHP page from the server. PHP can execute a JavaScript function at will simply by downloading it (with at least minimal HTML markup) to a browser. That seems pretty simple direct to me, considering that they're running in different computers. What's simple and direct to you may not be to others -- and I fully realize that both environments are running on different computers at different times -- it's the your perspective of at will I need to come to terms with. I can see how php can, and have used php to, generate a web page which has body onload=js() tag, which can pass a variable to js and will cause js to execute. But, isn't there anything else? Is that all there is? ... I also understand that php can generate html (have done it) and echo out javascript that may, or may not, run if js is present -- like Robert suggested in his WAHOOEY (LOL) example. But, that appears messy to me. If php wants to say something to js, then a page must be created -- it seems like a lot foreplay to get at the goodies. Without a downloaded page, what goodies are there? You know, you can download pure JavaScript, dressed only in a script tag, to a browser and have it execute without carrying with it a whole HTML page. Is that what you're looking for? What would such a script accomplish that a PHP program couldn't? I suppose it could interact with the human user with prompts, alerts, and confirms; gather information about the client such as monitor window size; grab local time to compare to server time. What else? If it has to create DOM nodes to interact with the user, haven't you come full circle and shouldn't you just download an HTML page to be JavaScript's environment? I guess what I'm looking for is something simpler -- is there? Paint me a picture of a hypothetical simpler situation; I'm intrigued. I think you have provided me with a clearer picture of what's going on and some things for me to consider. I need to pound some code. Thanks for your time and insight. tedd -- http://sperling.com -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] php - js (was Javascript Navigation)
At 08:03 AM 4/27/2006, tedd wrote: Forgive me my simplicity, but trying to tie communication between php with javascript is like trying to get the past and future to talk to each other -- they exist at different times. Normally, php is history when js steps on the stage and while js may say a few lines to php (i.e., Alas Poor Yorrick, I Knew Him ...), there isn't any real dialog. Additionally, with regard to the web, their activations are different. JS listens and responds to user activities whereas php only responds to a limited set of prompts. Ajax appears to blur the distinction somewhat, but it's still nothing more than a call from js to php and js has no idea if php's task was successful, or not. In other words, there is no real two-way communication. To me, what's needed to combine these two languages successfully is simply communication, such as: 1. A way to send information from js to php and have php act upon it. 2. A way to send information from php to js and have js act upon it. Then one of the two languages (most likely js) would need to have some sort of repeating polling mechanism where instructions could be handled -- an event loop. But Tedd, this is how so many web applications work now: PHP generates pages in which and on which JavaScript acts, and JavaScript helps direct to URLS, forms querystrings, and post form input back to the server. It's true that PHP can't know whether JavaScript will be running in the next page it delivers, so it has to generate pages that will be fully functional even if there's no one to talk to. It's easy to build in semaphores that let PHP know whether or not JavaScript was running in the page last posted, although as we know it should validate all the incoming data and not DEPEND on client-side scripting for anything. It's true that part of JavaScript's mandate is real-time user interaction which PHP can't touch, and part of PHP's mandate is file manipulation that JavaScript can't perform. So what? It's commonplace for different components of a complex system to have discrete functional domains. For what it's worth the two languages also share capabilities, such as creating and manipulating document elements, strings, and arithmetic calculations. The fact that their domains aren't identical is hardly a show-killer. To me, what's needed to combine these two languages successfully is simply communication, such as: 1. A way to send information from js to php and have php act upon it. URL, querystring, form input, and cookies. 2. A way to send information from php to js and have js act upon it. HTML, inline script blocks, dynamic script files, and cookies. I believe you're seeing monsters in the closet where there are only rumpled socks. Warm regards, Paul -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] php - js (was Javascript Navigation)
At 9:18 AM -0700 4/27/06, Paul Novitski wrote: I believe you're seeing monsters in the closet where there are only rumpled socks. I'm not trying to see, or create monsters, I'm just trying to understand. To me, what's needed to combine these two languages successfully is simply communication, such as: 1. A way to send information from js to php and have php act upon it. URL, querystring, form input, and cookies. Okay, I understand how js and html can communicate with php -- but, that's not the problem. My statement above was part of a symmetrical requirement regarding communication. 2. A way to send information from php to js and have js act upon it. HTML, inline script blocks, dynamic script files, and cookies. But, show me an example of php doing each of the above where js will receive the data and will act upon it. For example, if php creates a cookie, then how does js know that? How can the presence of a cookie cause js to run? Can js cycle reading cookies waiting for something to do while php crons writing them as needed -- and vise-versa? Is that a viable method of communication and activation between the two? Is there anything that php can do that will initiate a js routine? As far as I know (limited as I am) php can't even detect if js is present, or not, let alone cause a javascript routine to run -- is that not correct? If not, please give me an example of where php can make js run. Thanks. tedd -- http://sperling.com -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] php - js (was Javascript Navigation)
On Thu, 2006-04-27 at 13:33, tedd wrote: At 9:18 AM -0700 4/27/06, Paul Novitski wrote: Okay, I understand how js and html can communicate with php -- but, that's not the problem. My statement above was part of a symmetrical requirement regarding communication. Communication need not be symmetrical. All that is required is that each end understand one another. 2. A way to send information from php to js and have js act upon it. HTML, inline script blocks, dynamic script files, and cookies. But, show me an example of php doing each of the above where js will receive the data and will act upon it. See google maps or google suggest for excellent examples. For example, if php creates a cookie, then how does js know that? How can the presence of a cookie cause js to run? JS I do believe has access to the cookie. Either way, PHP is perfectly cable of informing JS of the cookie. Can js cycle reading cookies waiting for something to do while php crons writing them as needed -- and vise-versa? Is that a viable method of communication and activation between the two? Js can cycle, I don't suggest a while loop, it is better to use the system timer to do periodic polling. Is there anything that php can do that will initiate a js routine? As Yes: echo WAHOOEY html script language=javascript type=text/javascript goBabyGo(); /script body onLoad=goBabyGo() Why are you staring at me? /body /html WAHOOEY; far as I know (limited as I am) php can't even detect if js is present, or not, let alone cause a javascript routine to run -- is that not correct? If not, please give me an example of where php can make js run. You're thinking is erroneous. PHP can indeed detect if JavaScript is present. And as shown above it can cause a JavaScript routine to run. If someone disable's JavaScript, that is not the problem of PHP, that is akin to trying to run MS Winblows binaries under linux or vice versa -- the environment must be sane for the program to run. Cheers, Rob. -- .. | InterJinn Application Framework - http://www.interjinn.com | :: | An application and templating framework for PHP. Boasting | | a powerful, scalable system for accessing system services | | such as forms, properties, sessions, and caches. InterJinn | | also provides an extremely flexible architecture for | | creating re-usable components quickly and easily. | `' -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] php - js (was Javascript Navigation)
At 10:33 AM 4/27/2006, tedd wrote: At 9:18 AM -0700 4/27/06, Paul Novitski wrote: I believe you're seeing monsters in the closet where there are only rumpled socks. I'm not trying to see, or create monsters, I'm just trying to understand. Sorry, that was my attempt to be light-hearted and disarming~ Tedd, it almost seems as though one of your requirements for PHP-JavaScript communication is that there be PHP and JS scripts running continuously trading bits of information back and forth. The web model is quite different, with scripts starting up and ending with each page-load. A full-page round-trip to the server, as when you click on a hyperlink or submit a form, is one complete cycle of client-server communication. It is possible to trigger smaller increments of communication as Ajax/XMLHttpRequest demonstrates, but still each time you talk to the server you're starting a PHP script running from scratch on the server. This wake up/go to sleep model doesn't disqualify it, in my view, from constituting communication between two scripts. To me, what's needed to combine these two languages successfully is simply communication, such as: 1. A way to send information from js to php and have php act upon it. URL, querystring, form input, and cookies. Okay, I understand how js and html can communicate with php -- but, that's not the problem. My statement above was part of a symmetrical requirement regarding communication. Sorry -- symmetrical? Please elucidate, I'm not familiar with this term in this context. Which factors need to be the same on both sides of the Turing box lid for your criteria to be satisfied? 2. A way to send information from php to js and have js act upon it. HTML, inline script blocks, dynamic script files, and cookies. But, show me an example of php doing each of the above where js will receive the data and will act upon it. Well, first of all, JavaScript acts in the context of an HTML page. When PHP generates the page, PHP is providing JS with all the elements and attributes necessary to conduct its business. If JavaScript submits a form with particular input name/value pairs, PHP can respond by selecting data from a table and/or branching in its logic tree and generating a particular set of markup on the next page for JavaScript to operate on. PHP can output HTML markup containing data for JavaScript to operate on. PHP can output script blocks into an HTML document containing executable instructions including static and array variable definitions. PHP can dynamically supply external JavaScript files, literally cooking the JS scripting logic from server-side. For example, if php creates a cookie, then how does js know that? How can the presence of a cookie cause js to run? Gecko DOM Reference DOM:document.cookie http://developer.mozilla.org/en/docs/DOM:document.cookie Also google javascript cookie e.g. http://www.netspade.com/articles/2005/11/16/javascript-cookies/ Can js cycle reading cookies waiting for something to do while php crons writing them as needed -- and vise-versa? Is that a viable method of communication and activation between the two? No, because cookie values are changed only on page submit load. To my knowledge, XMLHttpRequest is the only way for JavaScript to request receive PHP data during a single page-view. (Well, there is another way: JavaScript can create an Image object on the fly with a PHP script as the SRC and data on the quesrystring, but I haven't taken the trouble to cook up a scheme for PHP to deliver and JavaScript to extract information from an image bitstream so in my work this is a one-way communication channel.) This demonstrates that a single, continuously-executing JavaScript program can wait for responses from the server. The opposite is clearly true in principle -- the server's operating system waits for the next HTTP request from the client -- although I suspect that it would be excessively and unnecessarily burdensome on the server to have a PHP script continue to execute in anticipation of the next client request. Much more efficient to have the operating system wake up the PHP interpreter and execute a script only when one flies in the window. Is there anything that php can do that will initiate a js routine? As far as I know (limited as I am) php can't even detect if js is present, or not, let alone cause a javascript routine to run -- is that not correct? If not, please give me an example of where php can make js run. PHP can initiate JavaScript execution simply by downloading an HTML page that contains JS script set to execute immediately or on a given event. Every time JavaScript runs in a page generated by PHP, PHP is essentially telling the JavaScript interpreter in the browser to execute the contained or linked script. PHP can select a particular JS function to execute based on various criteria by downloading code to
Re: [PHP] php - js (was Javascript Navigation)
At 10:33 AM 4/27/2006, tedd wrote: Can js cycle reading cookies waiting for something to do while php crons writing them as needed -- and vise-versa? Is that a viable method of communication and activation between the two? At 01:57 PM 4/27/2006, Paul Novitski wrote: No, because cookie values are changed only on page submit load. Let me re-answer that. Yes, cookies are an acceptable method of PHP-JavaScript communication -- when they're turned on in the client -- but require a new page load to synchronize changed values between client server. When I said no all I meant was that cookies don't work for communicating PHP-to-JavaScript within a single page-view. Paul -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] php - js (was Javascript Navigation)
At 1:57 PM -0700 4/27/06, Paul Novitski wrote: Okay, I understand how js and html can communicate with php -- but, that's not the problem. My statement above was part of a symmetrical requirement regarding communication. Sorry -- symmetrical? Please elucidate, I'm not familiar with this term in this context. Which factors need to be the same on both sides of the Turing box lid for your criteria to be satisfied? And At 3:16 PM -0400 4/27/06, Robert Cummings wrote: Communication need not be symmetrical. All that is required is that each end understand one another. Arrr... my head hurts :-) Okay, a little misunderstanding here. In my statement of symmetrical requirements regarding communication I basically said: 1. js - php 2. php - js I was simply using symmetrical *statements* to illustrate my point. I was not implying a requirement that all communications must be symmetrical, understand? Now, I know [1] that js can pass variables to php and cause it to run -- I do that using ajax -- that's not a problem. What I don't get is how php can pass variables to js and cause it to run at will. I can see how php can, and have used php to, generate a web page which has body onload=js() tag, which can pass a variable to js and will cause js to execute. But, isn't there anything else? Is that all there is? Paul you said: All this seems very obvious to me, but knowing your level of sophistication with programming I'm led to suspect that perhaps I'm not understanding your question properly. Thanks for the compliment, but I can be as dumb as a post about things until I fully understand them. However, everything you said I understand. I understand that XMLHttpRequest works -- I'm a little fuzzy about how -- but, I have used it to both send data to php and to cause php to execute. That's not a problem. I also understand that php can generate html (have done it) and echo out javascript that may, or may not, run if js is present -- like Robert suggested in his WAHOOEY (LOL) example. But, that appears messy to me. If php wants to say something to js, then a page must be created -- it seems like a lot foreplay to get at the goodies. I guess what I'm looking for is something simpler -- is there? tedd PS: WAHOOEY indeed -- LOL, I'm still chuckling about that. -- http://sperling.com -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] php - js (was Javascript Navigation)
On Thu, 2006-04-27 at 19:39, tedd wrote: At 1:57 PM -0700 4/27/06, Paul Novitski wrote: Okay, I understand how js and html can communicate with php -- but, that's not the problem. My statement above was part of a symmetrical requirement regarding communication. Sorry -- symmetrical? Please elucidate, I'm not familiar with this term in this context. Which factors need to be the same on both sides of the Turing box lid for your criteria to be satisfied? And At 3:16 PM -0400 4/27/06, Robert Cummings wrote: Communication need not be symmetrical. All that is required is that each end understand one another. Arrr... my head hurts :-) Okay, a little misunderstanding here. In my statement of symmetrical requirements regarding communication I basically said: 1. js - php 2. php - js I was simply using symmetrical *statements* to illustrate my point. I was not implying a requirement that all communications must be symmetrical, understand? Now, I know [1] that js can pass variables to php and cause it to run -- I do that using ajax -- that's not a problem. What I don't get is how php can pass variables to js and cause it to run at will. I can see how php can, and have used php to, generate a web page which has body onload=js() tag, which can pass a variable to js and will cause js to execute. But, isn't there anything else? Is that all there is? Paul you said: All this seems very obvious to me, but knowing your level of sophistication with programming I'm led to suspect that perhaps I'm not understanding your question properly. Thanks for the compliment, but I can be as dumb as a post about things until I fully understand them. However, everything you said I understand. I understand that XMLHttpRequest works -- I'm a little fuzzy about how -- but, I have used it to both send data to php and to cause php to execute. That's not a problem. I also understand that php can generate html (have done it) and echo out javascript that may, or may not, run if js is present -- like Robert suggested in his WAHOOEY (LOL) example. But, that appears messy to me. If php wants to say something to js, then a page must be created -- it seems like a lot foreplay to get at the goodies. I guess what I'm looking for is something simpler -- is there? There isn't something simpler, but that is necessitated by the stateless nature of the web, and the security requirements of the client (the poor sucker browsing the net :) I understand your desire for the simplicity of a desktop application, but anonymous data sources and trust aren't usually compatible. In the web paradigm the both the user and the server need to distrust one another by default which isn't the case for bought from a reputable, honest to goodness real live person, manually installed desktop application *grin*. Although, can't say I trust MS much. PS: WAHOOEY indeed -- LOL, I'm still chuckling about that. It was nice of PHP to let us name our heredoc delimiters. I guess the standard is EOF, but why write boring code ;) Cheers, Rob. -- .. | InterJinn Application Framework - http://www.interjinn.com | :: | An application and templating framework for PHP. Boasting | | a powerful, scalable system for accessing system services | | such as forms, properties, sessions, and caches. InterJinn | | also provides an extremely flexible architecture for | | creating re-usable components quickly and easily. | `' -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
Re: [PHP] php - js (was Javascript Navigation)
At 04:39 PM 4/27/2006, tedd wrote: What I don't get is how php can pass variables to js and cause it to run at will. Do you mean the way one function can call another function within the same program? It sounds like you're picturing PHP JavaScript executing continuously simultaneously. You aren't, are you? JavaScript can execute a PHP program at will simply by requesting a PHP page from the server. PHP can execute a JavaScript function at will simply by downloading it (with at least minimal HTML markup) to a browser. That seems pretty simple direct to me, considering that they're running in different computers. I can see how php can, and have used php to, generate a web page which has body onload=js() tag, which can pass a variable to js and will cause js to execute. But, isn't there anything else? Is that all there is? ... I also understand that php can generate html (have done it) and echo out javascript that may, or may not, run if js is present -- like Robert suggested in his WAHOOEY (LOL) example. But, that appears messy to me. If php wants to say something to js, then a page must be created -- it seems like a lot foreplay to get at the goodies. Without a downloaded page, what goodies are there? You know, you can download pure JavaScript, dressed only in a script tag, to a browser and have it execute without carrying with it a whole HTML page. Is that what you're looking for? What would such a script accomplish that a PHP program couldn't? I suppose it could interact with the human user with prompts, alerts, and confirms; gather information about the client such as monitor window size; grab local time to compare to server time. What else? If it has to create DOM nodes to interact with the user, haven't you come full circle and shouldn't you just download an HTML page to be JavaScript's environment? I guess what I'm looking for is something simpler -- is there? Paint me a picture of a hypothetical simpler situation; I'm intrigued. Paul -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php
