calling php using js - php

Question

ok so I have this in my HTML code:
<script type="text/javascript" src="load2.php"> </script>
I saw somewhere you could call a php file like that and the javascript contained in it will be rendered on the page once echoed.
So in my PHP file i have this:
while ($row = mysql_fetch_array($result, MYSQL_ASSOC)) {
$storeArray[] = $row['DayNum']; }
$length = count($storeArray);
I connected to my database and stuff and pulled those records and stored them in an array. Now my problem is alerting them using js. This is what I have:
echo " function test() {
for(var i = 0; i<$length; i++){
alert($storeArray[i]);
}
}
";
The test() function is being onloaded in my HTML page, but for nothing the values in the array won't alert. Any help please?

Answer 1

echo " function test() {
for(var i = 0; i<$length; i++){
alert($storeArray[i]);
}
}
";
This code is literally writing what you have written above. It's not completely clear, but I believe your intent is to loop over the contents of your database data, and alert that to the browser with alert() function.
You can achieve this in a couple of ways.
Write multiple alert statements
echo "function test() {"; //Outputting Javascript code.
for($i = 0; $i<$length; $i++){ //Back in PHP mode - notice how we aren't inside of a string.
$value = $storeArray[$i];
echo "alert($value)"; //Outputting Javascript code again.
}
echo "}"; //Outputting Javascript code to close your javascript "test()" function.
Write a Javascript array, then loop over it in Javascript
echo "function test() {";
echo " var storeArray = ['" . implode("','", $storeArray) . "'];";
echo " for (var i = 0; i < storeArray.length; i++) {";
echo " alert(storeArray[i]);";
echo " };";
echo "}";
Finally, you could use AJAX and JSON to load the data, rather than outputting a JS file from PHP. That is an entirely different topic, though, and you should search StackOverflow for more examples as there are numerous questions and answers involving it.

Answer 2

Unless your array contains only number, you probably have JS error. You should put your $storeArray[i] in quotes in the alert function so it considered as a string in js.
alert('$storeArray[i]');
Once printed out, the JS will look something like this
alert('foo');
alert('bar');
Whereas with your code, it would've printed it like this
alert(foo);
alert(bar);

Answer 3

in your php file include load2.php
header("Content-Type: text/javascript");
in the in the top. so your browser get what it wants.
$i=0;
$storeArray = array();
while ($row = mysql_fetch_array($result, MYSQL_ASSOC)) {
$storeArray[$i] = $row['DayNum'];
$i++;
}
echo "var arr = Array();";
echo "function test() {";
foreach ($storeArray as $key=>$item) {
echo "arr[".$key."] = ".$item.";";
}
echo "}";
echo "alert(arr);";
actually you can comment out the two echos containing the <script></script> part when including the file as <script src="load2.php" type="text/javascript" ...