Concatenation Question?

PHP
1 
$lo = 2;
$high = 7;
echo $lo < $high;

The above code outputs 1.

However,

echo $lo < $high . " string";

doesn’t concatenate " string" to that 1. Why is that?

I know there is a better way of doing all of the above, but I’m just trying to understand the concatenation issue.

Thanks!

2

Why are you trying to complicate simple thing?

I’m not sure about this codes below, but try,


    echo {$lo < $high}. " string";
3 
<?php
echo (int)( $lo < $high ) . " string";
4

i think this happen because, php does the operation first and cast the the ‘answer’ to a number ‘1’ is true, ‘0’ is false.

http://www.php.net/manual/en/language.operators.precedence.php

A word of caution - the dot operator has the same precedence as + and -, which can yield unexpected results.

Example:

<php
$var = 3;

echo "Result: " . $var + 3;
?>

The above will print out “3” instead of “Result: 6”, since first the string “Result3” is created and this is then added to 3 yielding 3, non-empty non-numeric strings being converted to 0.

To print “Result: 6”, use parantheses to alter precedence:

<php
$var = 3;

echo "Result: " . ($var + 3);

http://www.php.net/manual/en/language.operators.string.php

5

Thanks everyone for your replies and help. Your feedback has helped me to clarify what is happening and why it is not working.