i have a table with columns id, stud_id, stud_name, stud_email, marks. I want a form with 3 drop-down stud_id, stud_name, stud_email. if anyone select any one of the drop-down the others should fill automatically according to the selected field from database. Thanks in Advance.
i want something like this but with a single table
http://www.91weblessons.com/codeigniter-ajax-country-state-city-drop-down/
You didn't post any specifics so my answer can only be general, but so I'll just give you the logical flow of the process:
Javascript that watches the dropdowns for changes. If you have 3 dropdowns, you'll have to watch the first two. If you use jquery, it'll be something like: $('first_dropdown').change({//your ajax call goes here})
Your ajax call. From inside the watch function mentioned above, create an ajax script that calls a php function that gets the data you want to populate the next dropdown. We're not done with this script though, we'll come back to it later.
In your controller, call a function in your model like get_all_stud() and use that to get whatever data you need to populate the dropdown, and echo that data as json.
Now that your controller has returned data to the ajax function we can use it to populate the dropdown. Iterate the object and do something like $('second_dropdown).append({<option>//your data here</option>})
And then you'll repeat the whole thing so that the third dropdown watches for changes on the second dropdown
Related
I am currently using Jquery UI to display checkboxes, which right now, don't do anything!
you can see the current set up here: rickymason.net/letschat/main/home/
I am still trying to understand JSON, AJAX and Javascript...but i know they are required to make this work:
When the user checks one, or more of the checkboxes, I'd like it to refresh the thread list at the bottom of the page based on which list is checked.
I don't need exact code (though the more the merrier!), just a good outline on the process that needs to take place.
I'm using codeigniter, thus php and mysql. The thread list is generated based on a * query for the threads table. Then, it is filtered based on a session variable which contains all active filters (user input, AND i'd also like it to be selectable via the jquery select box).
Any help is greatly appreciated!
The magic word here is AJAX.
Use jQuery to bind to the events of the form elements
Send the event through AJAX calls to the server
Parse the response from the server and use javascript to update the page
On php page in a form, One combo box has list of my Customer from mysql table customer. Another combo box has invoiceno stored in invoice table which has respective customer records. I want to select customer from first combo box and filter invoiceno from the second one according to the customer. Any one help me for php or java or Jquery or both codeings? Means if I select customer1 then in the second combo box should show all invoiceno respective to the custermer1. No Refresh or ReLoad or Post form Pl. If I get the first selection in a php variable format example $customer, it is enough for me. Thanks for any one help me.
Based on what is given, i think one is only restricted to pushing you in the right direction. In a case where you there a large number of customers, it most likely be that you are working with a database, thus the following process:
The Page of the selects is where you will need to make an AJAX request on change of the select element.
Using your JavaScript of your favorite JavaScript library you'll make the request passing a value that you'll query your database for.
Ofcourse you'll need to configure your PHP for GET or POST depending of you AJAX request, then query the database.
Format the databases output to be a valid HTML of your selected element.
Earlier you'll have configured your AJAX script to populate the proper element once the request has been successful.
You dont want to POST to the script. You dont want to invoke any server side activity. And you want to get the value user selects into a PHP variable. From what I understand, this means, you dont clearly get where PHP plays a role. The way you want it, you might want to use XAJAX : http://www.xajax-project.org But even this causes various REQUESTs to the PHP script internally.
I would suggest the below:
Do a natural join in the SQL query.
For a customer C1, there might be 100 Invoice numbers I1. The result of the query may be outputted in a JSON format. Something like this:
"RESULT" : [
"C1" : ["I1", "I2", I3"],
"C2" : ["I11", "I22", I33"]
]
ALL the data will be sent to the browser. This data can be stored as a Javascript Object. Use JSON.parse("<PHP response here>");
Whenever the users selection changes in a combo box, have a function in Javascript to load the corresponding values in the second list.
EDIT: In case, you are dealing with a larger database, and you expect a larger dataset, I would HIGHLY recommend XAJAX -- Simple and easy! :-)
If AJAX is not an option, you must load all the things (include customer & invoice), then you can use pure javascript/css to do that. It's a dirty work around, but it works.
First, let says that you have n customer, so you will have 1 combo box to select the customer; and n combo box for the invoices that associated with them. Those invoice combobox may have id = their ids in database.
Hide all the invoice combobox, with css : display: none
Use javascript: onchange to get the change event in the customer combobox, then show the approriate invoice combobox(display:block). This can be done easily by css property of Jquery, or simply manipulate by javascript replace function (to replace the html class of the combobox)
I'm sure that this way works, but the price is that you must load all data of customers & invoices, which maybe huge. So that if possible, you should try the AJAX approach like Thrustmaster & Babiker propose.
I have a small PHP page which contains two drop down lists
I need to populate the second one according to the result selected in the first drop down list .... is this possible? In other words I need to use the value selected from the first drop down list and use it in the dB query used to populate the second drop down list (but this should be populated upon selection of the first drop down list.
If this is possible any hints please? (you can assume that I am able to populate the first drop down list from the dB)
Option 1: embed the data for the second select in the document as hidden elements or JS objects. A change event handler on the first select will populate the second select. A List Apart has an example dynamic select page.
Option 2: use AJAX. When the first select changes, make a request to the server for the contents of the second select, then populate it. With a JS library (such as jQuery), this becomes quite easy.
$('select#one').change(
function (evt) {
$('select#two').load('/thing/'+this.value);
}
);
"/thing/<val>" identifies your server side script to generate a list of items based on "<val>" (use the rewrite facilities of your webserver to resolve the URL path to the actual script). You could simply have it always generate <option> elements, but a better design would be to include a way to specify the result format, so it could output the list as <li>, using JSON or some other format.
$('select#one').change(
function (evt) {
$('select#two').load('/thing/'+this.value, {fmt: 'option'});
}
);
You will have to use AJAX to send the selection of the first dropdown to the server. You can then query the database and generate the second dropdown and send it back to the user.
You'll need an asynchronous call back to the server, without a page reload. (I doubt that you actually want to have a button that posts back to the server) So AJAX is something that can do exactly that. Add an AJAX call to your first dropdown's onchange event handler that posts the selection back to the server and returns the contents of the second dropdown. When the AJAX call returns the new values, you will use it to build your content for the second dropdown. Most of this is done in Javascript, of course, besides the actual server part, which will remain in PHP.
There's two ways of doing it. The old-school "select an option and submit to rebuild the page" method, which works pretty much universally, and the newfangled AJAX methods, to load the second dropdown's contents without refreshing the page.
Both have advantages/disadvantages, so it boils down to what's best for your purposes. The oldschool method doesn't require any javascript at all, but since it does round-trip the form through the server, you'll get the "clear the window and then redraw the page" flickering.
The AJAX method bypasses the refresh flicker, but also would no work on Javascript-disabled browsers. It does require a little bit more code, client-side, to handle the AJAX calls and population of the dropdown, but the server-side code would be pretty much the same for both methods: same queries, same retrieval loops, just different output methods.
#outis has good point use .change in jquery otherwise use onchange event in select code.
like
<select id='my_select' onchange='javascript:myfunc()'>
<option value='a'>a</option>
.
.
<option value='z'>z</option>
function myfunc(){
//write code to populate another dropdown based on selected value
}
You can see this Dynamically Populating Dropdown Based On Other Dropdown Value
I am writing the following in PHP:
i would like to have 2 dropdownlists, where the second one is populated from a mySQL dB according to the choice made on the first dropdown list. Then I would like to use the values of the selected values of the dropdownlist to call another PHP page in which I will generate a db query.
Eg:
List A: Car Manufactures (honda, nissan, etc)
List B: Models (accord, civic, etc)
Then I will have a submit button, to POST the values in another PHP file? (I have the basics of how to perform the above without having a dynamic list, but I tried this with AJAX, but I am having problems to pass the value of the second dropdownlist)
Any tips of how I can perform the above?
You should have a separate PHP file (let's call it search.php) which will take a POST variable (let's call it make) and run a query which will spit out a list.
After it spits out the list (one model per line, ends with a \n) you should have a bit of javascript which will then throws that into the second drop down.
Hitting the submit button should just be a form POST to another PHP file.
I'd suggest to make it without AJAX at first.
just make a first form using GET method. So, after submit this form, you'll land with a classical ?choice=1 query string on the second script. So, you can use $_GET['choice'] (properly sanitized of course) to query a database and populate second select.
Don't forget to add
<input type="hidden" name="choice" value="<?php echo htmlspecialchars($_GET['choice'])?>">
to the second form
solution found here:
http://www.plus2net.com/php_tutorial/php_drop_down_list.php
I have created a page in PHP, in that i need to load a dropdown2 corresponding to the value of dropdown1 without refreshing the page. The values for those dropdown's are from the database.
I dont want to refresh the page for every click.
two when you have sent your page to the client, PHP is done. all you got there is JavaScript.
Ajax: you can use Ajax calls, when your first dropdown is selected. define a function in JavaScript, so when an option in the first dropdown is selected, it will call a URL, and send the ID of the selected item to that URL, and fetch the XML result and use that to populate the second dropdown.
JavaScript Arrays: this approach is like the other, the difference is that all data of both dropdowns are already sent to the client in the page, as Javascript objects, or arrays. by selecting an option from the first dropdown, your JavaScript function will populate the second dropdown using local Arrays, or Objects, instead of calling an Ajax call.
the second method has the benefit that changing the second dropdown is faster, and will not require another connection. but the first time the page is loading will take longer, because all of your dropdowns data should be loaded first. I have used the second method in some of my pages, but if you have a tremendous amount of data to fetch for each option of your first dropdown, the better way is the first one.
I recommend using a well-known framework for these, like jQuery. it will ease all of your
work. you can call ajax calls, and change children of the second dropdown easily.
edit:
in the first method (AJAX call) I said load data from XML. I meant making an AJAX connection to the server, to some PHP page that will accept an argument, like the value of selected option in the first select tag, and then searches the database on the server, fetches related results and returns an XML document that have all the vlues for the second select tag. and in your JavaScript function that made the Ajax request, you can parse that XML and create option tags for second select tag on the fly, based on the result XML. your PHP script accepts a value and can do anything based on that value. the XML part, is just a transfer tool.