Do you know the difference between echo and print in php?

This article mainly introduces the difference between echo and print in PHP. It provides a more in-depth summary and analysis of the common usage differences between the two. Friends in need can refer to it

Generally speaking , dynamic output of HTML content in PHP is achieved through print and echo statements. In actual use, the functions of print and echo are almost exactly the same. It can be said that wherever one can be used, the other can also be used. However, there is still a very important difference between the two: in the echo function, multiple strings can be output at the same time, while in the print function, only one string can be output at the same time. At the same time, the echo function does not require parentheses, so the echo function is more like a statement than a function.
echo and print are not functions, but language constructs, so parentheses are not required.

Their difference is:

(1) echo can output multiple strings , like the following:

echo 'a','b','c';

If you must add parentheses, note that writing echo ('a','b','c'); is wrong. It should be written as:

echo ('a'),('b'),('c');

It does not behave like a function, so it cannot Context used for functions
(2) print can only output a string, it can behave like a function, for example you can use it as follows:

$ret = print 'Hello World';

all it can use In more complex expressions.
In addition, echo is relatively efficient!

Look at the following code:

<?php
$a=&#39;hello &#39;;$b=&#39;php world!&#39;;echo $a,$b.&#39;<br />&#39;;//echo 可以用逗号分隔字符串变量来显示
print $a.$b.&#39;<br />&#39;;//而print不能使用逗号，只能用点号分隔，
//print $a,$b.&#39;<br />&#39;;//这里使用逗号时报错。
?>

Analysis summary:

echo command is the same as print command, there is no difference
echo function and print function There is a difference.
echo() No return value, the same as the echo command
print() There is a return value, success returns 1, false, returns 0.
printf() and sprintf() is similar, both are formatted output, the difference is that the former outputs to standard output, the latter outputs to variables

Form:

echo  <<< EOT 
EOT; 
print  <<< EOT 
EOT;

The writing format of , its meaning is as follows:

Operator, the content between the custom delimiters will be regarded as a string, and the variables in between can be processed
EOT Custom delimiter, the end must be at the beginning of the line

I believe that what this article describes has certain reference value for everyone to better master PHP programming.

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