Do you know the ++ operator?

In the previous article, we learned about the error control operator. If you need it, please read "Have you ever used the @ operator in PHP? 》. This time we introduce to you another operator, the increment operator. You can refer to it if you need it.

In php, there is such an operator. The name of this operator is called the increment operator. Next, let’s take a look at this operator.

Increment means increasing in sequence. We also understand that this operator can add a certain number to the value each time.

Let’s take a look at a small example.

<?php
echo "<h3>第一次</h3>";
$a = 5;
echo "首先是: " . $a++ . "<br />\n";
echo "其次是: " . $a . "<br />\n";

echo "<h3>第二次</h3>";
$a = 5;
echo "首先是: " . ++$a . "<br />\n";
echo "其次是: " . $a . "<br />\n";
?>

Let’s take a look at this result again

Why is this result different? The naming uses “ ” This operator, why is it that the first time, it starts with 5, and after using the " " operator, it becomes 6; and the second time, it starts with 6, and after using the " " operator, it remains 6, why is there no change? ? Doesn't this operator work?

Let's take a look at this code again. We can see that the first time is " " used after "$a"; and the second time is after "$a" "$a" was used before "

". It seems that this is the reason for the different results.

The increment operator performs the simple task of incrementing its operand by one.

This operator mainly appears in two forms. It appears in front of the variable that works. This is the prefix mode. The second way, appears after the variable that works, this is the suffix mode.

That is to say, if it is used in front of a variable, the increment operation will be performed first, and then the variable will be output; if it is used after the variable, the variable will be output first, and then the increment operation will be performed. Okay, that’s all. If you want to know anything else, you can click this. → →

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