Implementation code for passing variables between php and javascript

PHP variable to Javascript variable:

 
<?php $myvar=10; ?> 
<script type="text/javascript"> 
jsvar = <?php echo $myvar; ?>; 
document.write(jsvar); // Test to see if its prints 10: 
</script> 

Form variable to Javascript variable:

 
<form name="myform4"> 
<input type="hidden" name="formvar" value="100"> 
</form> 
<script type="text/javascript"> 
jsvar = document.myform4.formvar.value; 
document.write(jsvar) // test 
</script> 

PHP variable to Form variable:

 
<form name="myform4"> 
<input type="hidden" name="formvar" value="<?php $phpvar=10; echo $phpvar; ?>"> // PHP code inside HTML!! 
</form> 

Javascript variable to Form variable:

 
<form name="myform3"> 
<!-- It needn't be a "hidden" type, but anything from radio buttons to check boxes --> 
<input type="hidden" name="formvar" value=""> 
</form> 
<script type="text/javascript"> 
jsvar=10; 
document.myform3.formvar.value = jsvar; 
</script>