What does this php syntax mean "$string{0}"

Question

I came across $string{0} here: https://github.com/bluerhinos/phpMQTT/blob/6c15cef0b1b2cb4c438e526c78d805b69a733f9d/phpMQTT.php#L154

I'm struggling to understand the {0} part of it. Does it mean the last character, the first character, the last digit in binary representation, the first digit in binary representation?

Is it still compatible with PHP 7.1?

So, __what__ is the problem with creating a sample script and see how it works? — u_mulder, Dec 12 '17 at 17:03

score 3 · Accepted Answer · answered Dec 12 '17 at 17:06

3

$string{0} is similar to $string[0], which will print the character at 0th index in $string variable.

answered Dec 12 '17 at 17:06

ash__939

1,614
2
12
21

axiac · Answer 2 · 2017-12-12T17:12:33.033

1

It is string access and modification by character. Since PHP 5.5 it also works with string literals.

edited Dec 12 '17 at 17:12

answered Dec 12 '17 at 17:04

axiac

68,258
9
99
134

5.5 just introduced character access to a string *literal*, e.g. `"foo"[0]`. I think string variables have worked since, well, forever. – iainn Dec 12 '17 at 17:10
@iainn You're right, I didn't read the documentation careful enough on the first time. I corrected the answer. – axiac Dec 12 '17 at 17:13

musashii · Answer 3 · 2017-12-12T17:13:03.983

1

Characters within strings may be accessed and modified by specifying the zero-based offset as in $str{42}

~~However, this syntax is deprecated as of PHP 6. Use square brackets instead.~~

Looks like the German manual needs an update; thx to iainn for pointing it out!

source

edited Dec 12 '17 at 17:13

answered Dec 12 '17 at 17:05

musashii

445
6
13

5

I think the German manual might need an update there, since PHP 6 isn't a thing. Both square and curly brackets are valid. – iainn Dec 12 '17 at 17:06
hmm, good catch – musashii Dec 12 '17 at 17:07

What does this php syntax mean "$string{0}"

3 Answers3