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This article mainly explains "how to locate the elements of strings and arrays in PHP". Interested friends may wish to have a look. The method introduced in this paper is simple, fast and practical. Let's let the editor take you to learn how to locate elements in strings and arrays in PHP.

Strstr function-locates string elements

In PHP, you can use the strstr function to search for the first occurrence of a string in another string. The basic syntax format of the strstr function is as follows:

Strstr (string,search,before_search)

It should be noted that: parameter string represents the string to be searched, parameter search represents the string to be searched, if the parameter is not a string, then this parameter will be converted to an integer and used as the sequence number of characters, the parameter before_search defaults to false, and if set to true, the returned result is the part of the string before the parameter search appears for the first time.

The return result of this function is the rest of the string starting from the match point, and if the string to be searched is not found, the result is flase.

Next, let's take a look at the use of the strstr function through an example, as follows:

Output result:

In the above example, the result returned by the strstr function is the rest of the string we searched for. We accomplish the purpose of locating the string through the strstr function.

When it comes to positioning matching in PHP, we have to mention regular expressions. In the above, we completed the positioning string through the strstr function, and another function in PHP is the preg_grep () function. Let's take a look at its usage.

Preg_grep () function-locates array elements

When it comes to search location in PHP, the only thing that can't be bypassed is regular expressions. PHP provides preg_grep () to match array elements through regular expressions.

The basic syntax format of the preg_grep () function is as follows:

Array preg_grep (string $pattern, array $input [, int $flags = 0])

It should be noted that the parameter pattern is defined by a regular expression, that is, the pattern to be searched, the parameter input represents the array to be searched, and the parameter flags is generally set to PREG_GREP_INVERT to indicate that the result returned by the function at this time is an array of mismatched $pattern elements.

Next, let's take a look at the use of the preg_grep () function through an example, as follows:

Output result:

Through the above example, we can match to the array elements, and the value of the parameter flags is different, and the result returned by the preg_grep () function is also different.

At this point, I believe you have a deeper understanding of "how to locate the elements of strings and arrays in PHP". You might as well do it in practice. Here is the website, more related content can enter the relevant channels to inquire, follow us, continue to learn!

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