php inside javascript checkbox value - php

Question

I have a list list of checkbox with name of files that came froma DB. Then I have button for delete the files. I have the following code for the button:
<input type='button' id='submit_btn' onclick='eraseFile()' value='DELETE FILES' />
and the eraseFile function
...
<script type="text/javascript" language="javascript">
function eraseFile(){
var checekedFiles = [];
$('input:checked').each(function() {
checekedFiles.push($(this).val());
});
alert(checekedFiles); // it gives me all the checked values..good
<?php
echo "HElllo World";
?>
}
</script>
It gives an error "missing ; before statement" and "eraseFile is not defined"
Is it possible to write php inside javascript right??

Answer 1

Is it possible to write php inside javascript right??
Unless the PHP code is generating valid JavaScript, then no.
The reason eraseFile is being called undefined is that your echo statement is causing a syntax error since it is printing the string literal Hellllo World at the end of the JavaScript function which violates JavaScript syntax rules.

Answer 2

Yes, it is possible.
PHP is parsed on the server, so you will literally be printing "HElllo World" inside your javascript function, which would probably cause an error.
You might be looking do do the following:
<?php echo 'document.write("Hello World!");'; ?>

Answer 3

Your PHP output gets appended to your JS function making your javaascript look like this:
<script type="text/javascript" language="javascript">
function eraseFile(){
var checekedFiles = [];
$('input:checked').each(function() {
checekedFiles.push($(this).val());
});
alert(checekedFiles); // it gives me all the checked values..good
HElllo World //syntax error here
}
</script>
You can do this:
<script type="text/javascript" language="javascript">
function eraseFile(){
var checekedFiles = [];
$('input:checked').each(function() {
checekedFiles.push($(this).val());
});
alert(checekedFiles); // it gives me all the checked values..good
alert("<?php echo "HElllo World"; ?>");
}
</script>
This will give a pop-up saying 'Hello World'
To pass a value from your Javascript function to your PHP script, you can do this:
var yourJsVar = {assign value here};
url = "yourPHPScript.php?value=" + yourJsVar;
if (window.XMLHttpRequest)
{ // Non-IE browsers
req = new XMLHttpRequest();
req.onreadystatechange = someFunction;
//someFunction will get called when the PHP script is done executing
try
{
req.open("GET", url, true);
}
catch (e)
{
alert(e);
}
req.send(null);
}
else if (window.ActiveXObject)
{ // IE
req = new ActiveXObject("Microsoft.XMLHTTP");
if (req)
{
req.onreadystatechange = someFunction;
req.open("GET", url, true);
req.send();
}
}
In your PHP script:
$yourPhpVar = $_GET['value'];
I mentioned someFunction above that gets called after the PHP script completes execution. This is how it should look. (Note that this is on your Javascript)
function someFunction()
{
if(req.readyState == 4 && req.status == 200)
{
//this will only execute after your AJAX call has completed.
//any output sent by your PHP script can be accessed here like this:
alert(req.responseText);
}
}

Answer 4

Try to echo a meaningful javascript code, "Hello World" it's not a valid JS statement.
Try something like
<?php
echo "alert('HElllo World');";
?>

Answer 5

Where is your eraseFile function defined?
if it is not defined until after the place it is called, you will get that error.
Side note:
You can have php echo inside of the javascript, except what you have there will not do much...

Answer 6

Yes, you can use PHP code in you script files, but your code generate invalid script code here.
<?php
echo "HElllo World"; // becomes: HElllo World (text!) in JS
?>

Answer 7

It is possible to write PHP in Javascript, but it is not the best pratice. The way we normaly do this is through AJAX read the documentation : http://api.jquery.com/category/ajax/

Answer 8

Yes, it is possible to include PHP inside JavaScript, since the PHP will be executed on the server before the page contents are sent to the client. However, in your case, what is sent is the following:
<script type="text/javascript" language="javascript">
function eraseFile(){
var checekedFiles = [];
$('input:checked').each(function() {
checekedFiles.push($(this).val());
});
alert(checekedFiles); // it gives me all the checked values..good
HElllo World
}
</script>
This doesn't validate as JavaScript, since the "Helllo World" is not a valid JavaScript command. This is why the function isn't being defined properly. You need to replace the "Helllo World" string with an actual JavaScript command.