Check out example codes for "how to get a variable from php to javascript". It will help you in understanding the concepts better.

Code Example 1

//passing PHP variable to JavaScript
var myJSVar = <?php echo json_encode($myPHPVar); ?>;

Code Example 2

<script type="text/javascript">
// boolean outputs "" if false, "1" if true
var bool = "<?php echo $bool ?>"; 

// numeric value, both with and without quotes
var num = <?php echo $num ?>; // 7
var str_num = "<?php echo $num ?>"; // "7" (a string)

var str = "<?php echo $str ?>"; // "A string here"
</script>

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