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PHP PHP Basics (Retired) PHP Conditionals & Loops Conditionals

見綸 陳
見綸 陳
6,333 Points
Posted by 見綸 陳
見綸 陳
6,333 Points

Dots be used in the variable

In the conditionals. If the statement is true. We set variable $name = $first_name . ' ' . $last_name

--> What is the function of these two " . " ?

4 Answers

jcorum
jcorum
71,830 Points

One of the frustrating things about working in various languages is that sometimes they have different operators for the same thing. As you see from the above answers, concatenation in PHP uses a dot. Concatenation in Javascript, Java, Python, Ruby, however all use the more usual + sign. Concatenation in SQL is the double pipe ||. In Visual Basic and Excel VBA it is &. And there are others! Haskell uses ++.

Putting a + sign for . in PHP, or a . for + in Javascript, are common bugs for web programmers working in both Javascript and PHP.

見綸 陳
見綸 陳
6,333 Points
見綸 陳
見綸 陳
6,333 Points

Thanks for your post.

For someone want to know number operation in php http://php.net/manual/en/language.operators.arithmetic.php

Grace Kelly
Grace Kelly
33,990 Points
Grace Kelly
Grace Kelly
33,990 Points

The "." in php is called concatenation. This simply allows you to combine or concatenate the two strings together, for example:

<?php
$first_name = "Mike";
$last_name = "The Frog";
echo "Hello". " ". $first_name . " " . $last_name; //outputs "Hello Mike The Frog"

?>

The " " allows you to add a space in between each word.

Hope that helps!!

見綸 陳
見綸 陳
6,333 Points
見綸 陳
見綸 陳
6,333 Points

Thanks for explain more!

Gianmarco Mazzoran
Gianmarco Mazzoran
22,076 Points
Gianmarco Mazzoran
Gianmarco Mazzoran
22,076 Points

Hi,

this are concatenation operator here's you find the docs

In your case the . concatenate the two variables $first_name and $last_name with a space between them. The result will be stored in the variable $name.

here's an example:

<?php

$first_name = "Gianmarco";
$last_name = "Mazzoran";

$name = $first_name . ' ' . $last_name;

// the result of the variable $name will be the concatenation of $first_name and $last_name with a space between them
'Gianmarco Mazzoran'

?>

Hope it helps!

見綸 陳
見綸 陳
6,333 Points
見綸 陳
見綸 陳
6,333 Points

Thanks for addition document link!!

DICKSON DZOKOTO
DICKSON DZOKOTO
1,313 Points
DICKSON DZOKOTO
DICKSON DZOKOTO
1,313 Points

The function of the two dot is the concatenation variable $first_name and $last_name