Sharing of classic examples of PHP functions

PHP, as a scripting language, is widely used in web development. Functions are an important part of PHP and one of the most commonly used functions in PHP development. This article will focus on some classic examples of PHP functions and share them with you.

1. strlen() function

The strlen() function is a function used in PHP to obtain the length of a string. It is very practical. Its use is very simple, just pass the string whose length you want to get as a parameter to the function. For example:

//Get the string length
$str = "hello world!";
$length = strlen($str);
echo " The string length is: ". $length;
?>

Output result:

The string length is: 12

2. substr() function

The substr() function is a function used to intercept strings in PHP, and it is also very practical. Its use is also very simple. You only need to pass the string to be intercepted, the starting position, and the interception length as parameters to the function. For example:

//Intercept string
$str = "hello world!";
$sub_str = substr($str, 0, 5);
echo "The intercepted string is: " . $sub_str;
?>

Output result:

The intercepted string is: hello

3. array_count_values() function

array_count_values() function is a function in PHP used to count the number of the same values ​​in an array, and it is very simple to use. Just pass the array to be counted as a parameter to the function. For example:

//Count the number of identical values ​​in the array
$arr ​​= array("apple", "orange", "banana", "apple", " apple");
$result = array_count_values($arr);
print_r($result);
?>

Output result:

Array
(

[apple] => 3
[orange] => 1
[banana] => 1

)

4. in_array() function

in_array() function is a function in PHP used to determine whether a specified value is in an array. Very practical. Its use is also very simple. You only need to pass the value to be judged and the array to be judged as parameters to the function. For example:

//Determine whether the specified value is in the array
$arr ​​= array("apple", "orange", "banana");
if( in_array("apple", $arr)){

echo "这个数组中有苹果！";  

} else {

echo "这个数组中没有苹果！";  

}
?>

Output result:

There are apples in this array!

5. date() function

The date() function is a function used to format dates in PHP and is very practical. Its usage is as follows:

//Format date
$now_time = time();
$date = date("Y-m-d H:i:s" , $now_time);
echo "The current date and time is:" . $date;
?>

Output result:

The current date and time is: 2021-12- 12 12:12:12

The above functions are very classic examples in PHP development. Their use is very simple, but they are very practical in actual development and can greatly improve development efficiency. I hope you can use it more in actual development.

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