Functions in PHP8: Practical application methods of str_contains()

With the release of PHP8, new functions and features have received widespread attention. Among them, the str_contains() function is undoubtedly a highly anticipated new feature. This article will introduce the practical application method of this function, hoping to help PHP developers use it better.

First, let’s take a look at the definition of the str_contains() function:

bool str_contains(string $haystack, string $needle): bool

This function is used to determine whether a string $haystack contains another string $needle. If it does, It returns true, otherwise it returns false. This function is very simple, but it has a wide range of application scenarios.

For example, suppose we have a string variable $subject and need to determine whether it contains a certain keyword $keyword. We can use the following code:

if (str_contains($subject, $keyword)) {
  // 包含关键词
} else {
  // 不包含关键词
}

This code passes The str_contains() function determines whether $subject contains $keyword. If it does, execute the code block in the if statement, otherwise execute the code block in the else statement.

This judgment method is very useful in many application scenarios. For example, in website development, we may need to display corresponding content based on the user's search keywords. In this case, we can use the str_contains() function to determine whether the keywords entered by the user match relevant content. For another example, in form validation, we can use the str_contains() function to determine whether the input content contains illegal characters.

In addition to simple string matching, the str_contains() function can also be used in combination with other functions to achieve more complex functions. For example, we can use the str_contains() function and substr() function to intercept the part of a string that contains a certain keyword, as shown below:

if (str_contains($subject, $keyword)) {
  $position = strpos($subject, $keyword);
  $result = substr($subject, $position, strlen($keyword));
  // 处理$result
} else {
  // 不包含关键词
}

This code first uses the str_contains() function to determine $ Whether subject contains $keyword, if so, execute the code block in the if statement. In this code block, we use the strpos() function to get the first occurrence of $keyword in $subject, and use the substr() function to intercept the part of the entire string that contains the keyword. With this method, we can process strings more precisely.

In addition to the above usage, the str_contains() function can also be used to filter strings, detect spelling errors, string pattern matching, etc. In short, this function is very practical and can do almost anything.

However, we need to note that the str_contains() function is only available for PHP8 and above. If your project is still using an older version of PHP, you cannot use this function. In addition, compared to old functions such as strpos() and strstr(), the str_contains() function has also improved in performance, but the specific differences need to be evaluated based on actual usage.

To sum up, the str_contains() function is a very practical string operation function, which can help us achieve a variety of functions. If your project has been upgraded to PHP8, you might as well try this new feature. I believe you will have a good experience.

The above is the detailed content of Functions in PHP8: Practical application methods of str_contains(). For more information, please follow other related articles on the PHP Chinese website!