too long

<?php 
    $i = 0;
    while($i<=10 ){
        echo '<label for=""></label><select name="comp'. $i++ .'></select><br>';
}
?>

I'm using this code for adding 10 select boxes on the html page, but instead only 5 select boxes are appearing, don't know why??

Is there any explanation, or my php is just drunk.....

 echo '<label for=""></label><select name="comp'. $i++ .'"></select><br>';

I think you are missing one double qoutes

'"></select><br>';
 ^

You missed double quota here:

<select name="comp'. $i++ .'>
                           ^------

it should be:

<select name="comp'. $i++ .'">

Your loop is fine and the code should run through 10 times, but you're missing a double quote on your echo line after $i++.

It should read something like:

echo '<label for=""></label><select name="comp'. $i++ .'"></select><br>';

That said, you might be little better off for clarity swapping out your while loop with a for:

<?php
    for($i = 0; $i < 10; $i++){
        echo '<label for=""></label><select name="comp'. $i .'"></select><br>';
    }
?>

The following code works as desired :

<?php
$i = 0;
while($i<=10 ){
    echo '<label for=""></label>';
    echo '<select name="comp'. $i++ .'"></select>';
    echo '<br>';
}
?>

you missed the '"' after $i++ in second echo statement