Add two strings together = 0 ???

[raytaylornz]

I have the following code and am trying to add the strings together to make a total.

The monthup and monthdown strings are extracted from a text file earlier in the script.

 

 

echo "$monthup <br>";

echo "$monthdown <br>";

$answer = $monthup + $monthdown;

echo $answer;

 

 

It outputs

 

36809697

565151504

0

 

The last line should be the other 2 added together which equals 601961201

 

Anyone got any ideas?

 

Thanks in advance for any help you can give. As you can see I am new to php.

[trq]

Strings are strings, not numbers. What exactly do you expect?

[raytaylornz]

Ok. I was hoping to add them together.

How would I do it then?

[Mchl]

[edited]

 

Tottally wrong answer was here

 

Try

 

$answer = (int)$monthup + (int)$monthdown;

[salathe]

Out of interest can you tell us what var_dump($monthup, $monthdown) outputs?

[Kloplop321]

you could do

echo "$monthup <br>";
echo "$monthdown <br>";
$answer = (int)$monthup + (int)$monthdown;
echo $answer;

or

$monthup = (int)trim($monthup);
$monthdown = (int)trim($monthdown);
echo "$monthup <br>";
echo "$monthdown <br>";
$answer = (int)$monthup + (int)$monthdown;
echo $answer;

You may need to cast them to numbers as an integer or a real number[ use (real) instead of (int)] before adding them together. if the variable has a space before the number by accident, trim() will remove it.

[Daniel0]

Or you know, he could just not add the HTML stuff right before he is going to treat it as a numeric value...

[Mchl]

He's just echoing it, not adding anything... something's strange here...

[nadeemshafi9]

strings are just arrays arnt they

[Daniel0]

strings are just arrays arnt they

 

In C, strings are arrays of chars, but that's not the case in PHP. Actually, there isn't even a char data type in PHP.

[nadeemshafi9]

so what your saying that the basic object string is a less complex object in php than in c

[Daniel0]

I don't know what you mean with "complex", but I would say it's more complex given that it has more features and you can dynamically change the size of it without having to reallocate memory manually.

[nadeemshafi9]

that makes sense in the c is simpler and closer lower level to the machine

[Mchl]

PHP strings can be accessed with array operator

 

<?php

$f = "PHP Freaks";

for ($i = 0; $i < strlen($f); $i++) echo $f[$i];

That's where confusion may be coming from.

 

However, you can't do this with foreach and is_array($f); will return false.

[nadeemshafi9]

i suppose it comes down to the strength of the type in the environment, i suppose if you start adding more functionality to types the line boundaries start to disappear