PHP and Javascript Variables

Anon

Is there an easy way to "share" a variable between javascript and PHP on a page that contains both languages? I can probably go one way with:
java_var = "<? echo $php_var; ?>;"

however, I need to go the other way... from a java variable (select.selectedIndex to a php var) to use in a select onChange javascript handler... the PHP script inside this handler needs to know which index is currently selected in the select form element.

Any ideas ??

Anon

I am a student learning JavaScript. If it is possible, how do I pass a variable from one script to another.
Here is my code.
Also I could use some information on events and handlers.

<head><title>Color Background A</title>
<script language="JavaScript">

<table align="center">
<tr>
<td align="center">
<script language="JavaScript">
document.write("<h1>Welcome ")
document.write(prompt("What is your name?",""))
document.write(" to the</h1>")
</script>
</td>
</tr>
<tr>
<td align="center">
<script language="JavaScript">
document.write("<h1>Background Color Changer</h1>")
</script>
</td>
</tr>
<tr>
</table>
<p>
<table align="center">
<td align="center">
<h1>Set the documents bgColor attribute.</h1></td>
</tr>
</table>
<form>
<table align="center">
<tr><td align="center">
<input type="button" value="Red" onClick="colorBackgroundRed()"></td>
<td align="center">
<input type="button" value="Green" onClick="colorBackgroundGrn()"></td>
<td align="center">
<input type="button" value="Blue" onClick="colorBackgroundBlu()"></td>
</tr>
</table>
<p> </p>
<table align="center">
<td align="center">
<script language="JavaScript">
function colorwrite()
{
document.write('<h4>You have changed the backgrouind color to '+clr+'.\n</h4>')
}
</script>
</td>
</tr>
</table>
</form>
</body>

Thank you
Randy Mason
ranmactutor@yahoo.com

Anon

I'm having the same problem.

In the following code I'd like to replace the <? echo $ectcountryid; ?> by the result of a javascript function returning the value of the selected option.

<a href="country_edit.php?fcountryid=<? echo $ectcountryid; ?>&econtactid=<? echo $econtactid; ?>">Pays</a>

Sorry I cannot help Mike, let's hope someone will ;-)

bpotier

Hi all,

Here are the three ideas that I was or am investigating:

Idea 1 - Closed :
input javascript code within the <a href="country_edit.php?data=document.form.myoption.value"> to send the value of the option to the php script.

This is not working, the javascript code is not evaluated

Idea 2 - Ongoing :
Perform a 'fake submit' of the form to be able to access the value in the second script and then cancel the submit
Should look like (code is wrong, just putting ideas on screen):

function validateSubmit() {
if (fakeSubmit) return false;
else return true;
}
</script>
...
<form action="submitScript.php" onSubmit="validateSubmit()">
...
<a href="javascript:fakesubmit()">test</a>
...
</form>

Idea 3 - To investigate
Temporary save the option value in the database (meaning even if not the correct option value for the record): submit the form but do not insert or update the definitive record, just a temp one to save the value of the option to work on.
Once processing of the option value is over, insert or update the db record with the true values

More coming soon ...

Mike Simonelli wrote:

Is there an easy way to "share" a variable between javascript and PHP on a page that contains both languages? I can probably go one way with:
java_var = "<? echo $php_var; ?>;"

Any ideas ??

bpotier

I found THE solution I think, at least when forms are concerned.

There's two alternatives:
- Hidden Form with Hidden fields updated with changes on main form and that you can submit without impacting the main form. Submitting the hidden form gives access to the php script to the forms elements current values that you duplicated in the hidden form hidden fields.

Main form submit triggering a "switch" php script that takes different actions based on the form state (ex: "2-Ready to submit", "1-Evaluate variables", etc.). This parameters comes from a main form hidden field whose value is updated by javascript. Submitting the form gives access to the php script to all the forms elements current values.

Mike Simonelli wrote:

Is there an easy way to "share" a variable between javascript and PHP on a page that contains both languages? I can probably go one way with:
java_var = "<? echo $php_var; ?>;"

Any ideas ??

Anon

Cool. However, do you think it is somehow possible to say, detect a person's browser version in a javascript at the top of the page and assign it to a variable, and then use the value of that variable later in the page in PHP?

Thanks in advance,
Pablo

Anon

Hi Pablo,

This is true that in this way (Javascript to PHP) things are a little bit different.

I think I have an idea but I'll test it first and reply in few days

Pablo Gosse wrote:

Thanks in advance,
Pablo

[deleted]

Hi ,I am new to PHP so haven't seen a lot of it, but I did face somewhat similar situation with Javascript and PHP.(php-javascript-php)

My main form has a dropdown box populated by php variables/php array .I select a value in the drop-down(select)and press a button. Using an onClick event handler on that button I call a Javascript function and pass the selected value(i.e. document.formname.fieldname.value in IE4, for Netscape you need to go a little different .fieldname[selectedIndex.value].value). The javascript function then calls a window opener in my case and appends the javascript variable with the code for window opener.
I can then assign this javascript variable to a php variable in the new window.
i.e. $php_variable = $submitted_javascript_variable and use it for database querries or whatever I want to.

So thats a php - javascript - php cycle for my specific case.

I am not very good at writing so might have got a bit confusing.Let me know if you have any questions.

Now , I have a question here, the above code works fine with PC but takes a damn long time on 'Mac' to execute. Do you or someone has an idea if the javascript + php combination works fine on all browsers and operating systems ?????

I need to get it fixed asap.

Thanks a lot for reading through and thanks for the anticipated reply.

Bipul....

Anon

this is kinda but it works....
the java script reads the selected value and reloads the page passing that in the url, upon the reload php reads the variable.

<?php
.....
echo "<script language='JavaScript'>\n";
echo "function reload(object){\n";
echo "var value = object.options[object.selectedIndex].value;\n";
echo "window.location ='search_contacts.phtml?Cust_id='+value;";
echo "}\n";
echo "</script>\n";
echo "<table><form name='form'><tr><td>\n";
echo "<b>Company Name:</b>\n";
echo "</td><td>\n";
echo "<select name='cust_id' onChange='reload(document.form.cust_id)'><option value=NULL> </option>\n";
$sql = "select Customer_Id, Customer_Name from customers;";$result = mysql_db_query ("db_name", $sql);
while ($row = mysql_fetch_array ($result)){
if (($row["Customer_Id"] == $Cust_id)) {
echo "<option value=".$row["Customer_Id"]." selected>".$row["Customer_Name"]."</option>\n";
}else{
echo "<option value=".$row["Customer_Id"].">".$row["Customer_Name"]."</option>\n";
}
}
echo "</select>\n";
echo "</td><td>\n";
echo "<b>Locations:</b>\n";
echo "</td><td>\n";
if ($Cust_id){
echo "<select name='loc_id'><option value=NULL> </option>\n";
$sql = "select Location_Id, Address1 from locations where Customer_Id='$Cust_id';";
$result = mysql_db_query ("db_name", $sql);
while ($row = mysql_fetch_array ($result))
echo "<option value=".$row["Location_Id"].">".$row["Address1"]."</option>\n";
echo "</select>\n";
}else{
echo "<select name='loc_id'><option> </option><option>select company first</option></select>\n";
}