Exploring the usage of in_array function in php, phpin_array_PHP tutorial

Exploring the usage of in_array function in php, phpin_array

This article explores the usage of in_array function in PHP in depth. Share it with everyone for your reference. The details are as follows:

Today I suddenly thought that the in_array function in PHP has a strange usage. Let’s take a look at this usage. Friends in need can simply refer to it. The code is as follows:

Copy code The code is as follows:

$a=array("1,2,3","4");
if(in_array(1,$a)){

echo "Condition is established";
}

This condition is indeed established. According to my thinking logic, the above condition is only established when the value of parameter 1 is "1, 2, 3" and the sum is 4, but the strange thing is that it is actually established, and then tested In the following situation, the code is as follows:

Copy code The code is as follows:

$a=array("a,2,3","4");

if(in_array('a',$a)){

echo "The condition is not met";

}

This is not true. In the first test case, if parameter 1 is written as '1', the condition is also not true. The conclusion is:

In PHP, if the first parameter is a number - an unquoted number, and the second array parameter contains a string starting with that number, it does not matter whether the first parameter is the complete second parameter. Elements will return true values. In other words, the in_array function does not match the entire element according to my thinking logic every time, or do I not understand the data type clearly enough?

At the same time, I also found that if the first element of your array is 0, problems will also occur. See the following situation, the code is as follows:

Copy code The code is as follows:

$a=array(0,"m");
if(in_array('mc6',$a))
{
echo "=====";
}

Interested friends can test and run the example described in this article, I believe there will be new gains!

I hope this article will be helpful to everyone’s PHP programming design.

http://www.bkjia.com/PHPjc/917036.htmlwww.bkjia.comtruehttp: //www.bkjia.com/PHPjc/917036.htmlTechArticleExploring the usage of in_array function in php, phpin_array This article takes a more in-depth exploration of the usage of in_array function in php. Share it with everyone for your reference. The details are as follows: Today I suddenly thought of...