The difference between using ',' and '.' in php_PHP Tutorial

The difference between using ',' and '.' in php

$str1 = ‘hello’;

$str2 = ‘ ‘;

$str3 = ‘world’;

　$str = $str1 . $str2 .$str3;

echo $str,’

　; // hello world;

// Questions for newbies, even those who have been working for half a year.

// How to use ','

echo $str1,$str2,$str3,’

　; // hello world

echo $str1 . $str2 . $str3 . ‘

　; // hello world

　/*

This line is $str1, $str2, $str3 in memory, splicing operation,

Calculate a large string of 'hello world',

Then echo it to get the result of the judgment

echo $str1 . $str2 . $str3 . ‘

　; // hello world

echo $str1,$str2,$str3,’

　; // hello world

Echo is a statement, responsible for output,

You can split by ',' to output multiple variables or values ​​at once.

In summary:

Use ‘ . ‘ to splice first and then output the whole.

Use ‘ , ‘ to output the three variables one by one.

During the interview, you will encounter this question:

In the above two cases, which one is faster and more efficient, use ',' or '.'?

Answer: Comma is faster because it saves a splicing calculation process.

http://www.bkjia.com/PHPjc/371361.htmlwww.bkjia.comtruehttp: //www.bkjia.com/PHPjc/371361.htmlTechArticleThe difference between ' and .' in php $str1 = hello; $str2 = ; $str3 = world ; $str = $str1 . $str2 .$str3; echo $str, ; // hello world; // Questions for newbies, even those who have been working for half a year. //...