php remove space elements from array

In PHP development, we often encounter situations where we need to delete space elements in arrays. Removing space elements can make it easier for us to operate arrays and improve program efficiency. This article will introduce various methods to remove space elements from arrays.

Method 1. Use the array_filter function

PHP has a very convenient built-in function array_filter, which can remove empty elements and false elements from the array. We can remove all space elements in the array by using the array_filter function.

Code example:

$arr = array("hello", "world", "", " ", "php");
$arr = array_filter($arr);
print_r($arr);

The above code will output:

Array
(
    [0] => hello
    [1] => world
    [4] => php
)

As shown in the above code, we first define an array $arr, which contains space elements. Then we use the array_filter function to operate on it, and finally return a new array with whitespace elements removed.

Method 2. Use foreach loop to traverse the array

In addition to using the array_filter function, we can also use the foreach loop to traverse the array and operate on it during the loop.

Code example:

$arr = array("hello", "world", "", " ", "php");
foreach ($arr as $key => $value) {
    if ($value == "" || $value == " ") {
        unset($arr[$key]);
    }
}
print_r($arr);

The above code will output:

Array
(
    [0] => hello
    [1] => world
    [4] => php
)

As shown in the above code, we use a foreach loop to iterate through the elements in the array in sequence, and then use the unset function to delete It is a space element. The final output is the same as in the previous example.

Method 3. Use the array_map function

In addition to the array_filter function, we can also use the array_map function to delete space elements in the array. The array_map function can apply the specified function to each element of the array.

Code example:

$arr = array("hello", "world", "", " ", "php");
$arr = array_map("trim", $arr);
$arr = array_filter($arr);
print_r($arr);

The above code will output:

Array
(
    [0] => hello
    [1] => world
    [2] => php
)

As shown in the above code, we first use the array_map function to remove spaces from each element in the array. Then use the array_filter function to delete empty elements.

Method 4. Use regular expressions

Finally, we can delete space elements in the array by using regular expressions. The preg_grep function takes a regular expression as a parameter and returns an array of elements in the array that match the regular expression.

Code example:

$arr = array("hello", "world", "", " ", "php");
$arr = preg_grep("/\S/", $arr);
print_r($arr);

The above code will output:

Array
(
    [0] => hello
    [1] => world
    [4] => php
)

As shown in the above code, we use the regular expression "/\S/" to match all non-space elements, Finally returns a reconstructed array.

Summary

The above are the four methods introduced in this article to delete space elements in PHP arrays. No matter which method is used, the space elements in the array can be removed to facilitate our array operations. In actual development, we can choose different methods according to specific situations and use them in conjunction with actual needs.

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