PHP - 在var上添加了混合字符串和变量？

Question

What am I doning wrong in my formatting for these 2 bits of code?

How can I format the mixture of strings and vars to give me the proper output?

$inbody = 60;
$body = "Welcome. For about " . $inbody . "-" . $inbody+15 . " minutes, you'll receive SMS messages." ;

Am I allowed to do inline addition like that? or is my only solution to just declare another variable and put it in? like:

$addedinbody = $inbody + 15 ;

Here is another example IM having trouble with (specifically setting the $body variable):

for ($i=0; $i<=$duration; $i++){
$body = $i+1 . "/" . $duration+1 . " " . $task[$newtask];
}

Answer 1

You need to put the addition in the bracket to tell that there is addition.

Like it:

$body = "Welcome. For about " . $inbody . "-" . ($inbody+15) . " minutes, you'll receive SMS messages." ;

And you problem will be solved.