Program not working

[madhanrajesh210002]

hi

I'm trying to calculate string's integer value with the help java script,
i write java script in a function and i call it when ever i need to do that calculation, but it seems not working

<?php
function cal($x)
{
echo "<br>";
echo "x value =".$x;
$calculation= "<script type=\"text/javascript\">"."document.write(eval($x));"."</script>"; 
echo "<br>";
echo "calculated value".$calculation;
echo "<br>";
return $calculation;
}
 
$x="10";
$a= cal("$x+5");
echo "<br>";
echo "a value now".$a;
echo "<br>";
 
$b="$a+5";
echo "<br>";
echo "now b value=".$b;
 
echo "<br>";
$c= cal("$a+5");
?>
 
 

first time ($a= cal(..)) is working but, the same function in second time ($b=cal(..)) by using previous values is not working.
KINDLY POINT OUT THE PROBLEM and help to solve it.

[JKing]

You are directly setting your values to $b without passing them through your function.

$b="$a+5";
 
//Should be
$b = cal("$a+5");
 

[madhanrajesh210002]

no its not working,

even
$c= cal("$a+5"); or $c= cal($b); same,

but the out put on second time the function cal, calling, its seems out puts wrong , kindly help to solve

[JKing]

This doesn't work because the way the everything is being processed. The script doesn't know the value of $b until the value of $a is determined. Since value $a is determined client side there is no way for the server to pass the calculated value of $a.

[JKing]

You can try php's eval()

<?php
    function cal($x)
    {
        echo "<br>";
        echo "x value =".$x;
        eval("\$calculation=$x;");
        echo "<br>";
        echo "calculated value".$calculation;
        echo "<br>";
        return $calculation;
    }
 
    $x="10";
    $a= cal("$x+5");
    echo "<br>";
    echo "a value now".$a;
    echo "<br>";
 
    $b=cal("$a+5");
    echo "<br>";
    echo "now b value=".$b;
 
    echo "<br>";
    $c= cal("$b+5");
    echo "<br>";
    echo "now c value=".$c;
?>

[kovik]

PHP has it's own eval() function. It cannot access the values that are generated by JavaScript.

EDIT: Didn't realize JKing posted... I've had this post up for a while and forgot about it. lol