How to pass string into if condition statement in php?

Question

I have stored conditions in database string format. ex: ((25>1)||(25<1)) How can I pass this string to if condition statement. I tried, but it's not working. I have used eval() function, but it's not working.

$con=eval("return ((25>1)||(25<1))");
if($con){
    echo "success";
}
else{
    echo "failed";
}

_Parse error: syntax error, unexpected end of file, expecting '**;**' : eval()'d code on line 1_ — AbraCadaver, Apr 11 '19 at 14:32
`$con=eval("return ((25>1)||(25<1));");` http://sandbox.onlinephpfunctions.com/code/55f1b71dba75a8af7427cf396a3c06bb96fe98a6 — executable, Apr 11 '19 at 14:34
@AbraCadaver sorry i forgot to add semicolon inside of eval 1)||(25<1));"); if($con){ echo "success"; } else{ echo "failed"; } ?> — siva.picky, Apr 11 '19 at 14:37
@AbraCadaver my doubt instead of eval any alternative is their? — siva.picky, Apr 11 '19 at 14:39
You didn't ask for an alternative you said _i have use eval() function but not working_ Without writing your own parser I don't know of an alternative. — AbraCadaver, Apr 11 '19 at 14:40
If you have a database you might be able to `SELECT ((25>1)||(25<1)) AS result` — AbraCadaver, Apr 11 '19 at 14:43
@AbraCadaver Okay thanks!. if it's string working but mine saved as json — siva.picky, Apr 11 '19 at 14:57
OK, then decode it. You keep commenting things that should be in your question. — AbraCadaver, Apr 11 '19 at 14:59

score 1 · Answer 1 · answered Apr 11 '19 at 15:01

1

You can do like this as well:

echo (25 > 1 ? "success" : ( 25 < 1 ? "success" : "failed")) ;

answered Apr 11 '19 at 15:01

PrakashG

1,642
5
20
30

this conditional statement okay. but my question is how to convert string ex: ((25>1)||(25<1)) this directly pass to if condition, i tried now eval worked but most of say eval is not safe so i try finding any other alternative, do you know something alternative for this? – siva.picky Apr 11 '19 at 15:05

Miroslav Glamuzina · Answer 2 · 2019-04-11T14:59:25.710

0

You are missing a semicolon in your eval(). Strings passed into eval() still must be valid PHP, which will need an ;.

$con = eval('return ((25>1)||(25<1));');
if($con) {
    echo 'success';
} else {
    echo 'failed';
}

edited Apr 11 '19 at 14:59

answered Apr 11 '19 at 14:57

Miroslav Glamuzina

4,472
2
19
33

This working thanks!. is that any alternate for eval? – siva.picky Apr 11 '19 at 14:58
Why would you need an alternative? – Miroslav Glamuzina Apr 11 '19 at 14:59
because i searched most of say don't use eval . – siva.picky Apr 11 '19 at 15:01
I've found some different ways to do it from this post, is this what you are looking for? https://stackoverflow.com/a/17700065/5066625 – Miroslav Glamuzina Apr 11 '19 at 15:02
Using eval isn´t a good thing, but as long as there is no (un-validated) user input, it´s fine security wise. – Manuel Mannhardt Apr 11 '19 at 15:06

How to pass string into if condition statement in php?

2 Answers2