substr_compare - PHP code example

How to Use the PHP Function Substr_Compare to Compare Two Strings

PHP is one of the most popular scripting languages in the world. It is used to build websites, generate dynamic content, collect form data, create and manage databases, encrypt and decrypt data, and more. It is free to use and very powerful, with the ability to handle a variety of different data types.

However, working with strings can sometimes be a pain in PHP. This is especially true when trying to compare two strings for a match. While there are several ways to do this in PHP, many of them require a large number of parameters and may cause a lot of error messages. In this article, we will learn how to use a new function in PHP called substr_compare that simplifies the process of comparing two strings by requiring only a single parameter.

The php function substr_compare compares the start position of the main string with a specific string, and it returns 0 if the string is found or -1 if the search was unsuccessful. It also takes an integer value as a starting point (offset) for the comparison, and it is optionally case-insensitive.

If you’re working with nested arrays in PHP, this will not work and will raise a fatal error: “Fatal Error: Uncaught TypeError: Argument #2 ($needle) must be of type str or null” (or an equivalent). The good news is that PHP has made great progress with types since version 8.0. Now, you can declare a property as a union type and mix different data types in the same variable.

substr_compare example

return self::setCacheResult($cacheKey, false);
            }
        } else {
            $address = $ip;
            $netmask = 32;
        }

        if (false === ip2long($address)) {
            return self::setCacheResult($cacheKey, false);
        }

        return self::setCacheResult($cacheKey, 0 === substr_compare(sprintf('%032b', ip2long($requestIp)), sprintf('%032b', ip2long($address)), 0, $netmask));
    }

    /** * Compares two IPv6 addresses. * In case a subnet is given, it checks if it contains the request IP. * * @author David Soria Parra <dsp at php dot net> * * @see https://github.com/dsp/v6tools * * @param string $ip IPv6 address or subnet in CIDR notation * * @throws \RuntimeException When IPV6 support is not enabled */

        $smarty->force_compile = $force_compile;
        $_count = 0;
        $_error_count = 0;
        // loop over array of template directories         foreach($smarty->getTemplateDir() as $_dir) {
            $_compileDirs = new RecursiveDirectoryIterator($_dir);
            $_compile = new RecursiveIteratorIterator($_compileDirs);
            foreach ($_compile as $_fileinfo) {
                if (substr(basename($_fileinfo->getPathname()),0,1) == '.' || strpos($_fileinfo, '.svn') !== false) continue;
                $_file = $_fileinfo->getFilename();
                if (!substr_compare($_file, $extention, - strlen($extention)) == 0) continue;
                if ($_fileinfo->getPath() == substr($_dir, 0, -1)) {
                   $_template_file = $_file;
                } else {
                   $_template_file = substr($_fileinfo->getPath(), strlen($_dir)) . DS . $_file;
                }
                echo '<br>', $_dir, '---', $_template_file;
                flush();
                $_start_time = microtime(true);
                try {
                    $_tpl = $smarty->createTemplate($_template_file,null,null,null,false);
                    if ($_tpl->mustCompile()) {

return parent::endsWith($suffix);
        }

        if ('' === $suffix || !preg_match('//u', $suffix)) {
            return false;
        }

        if ($this->ignoreCase) {
            return preg_match('{'.preg_quote($suffix).'$}iuD', $this->string);
        }

        return \strlen($this->string) >= \strlen($suffix) && 0 === substr_compare($this->string, $suffix, -\strlen($suffix));
    }

    public function equalsTo(string|iterable|AbstractString $string): bool
    {
        if ($string instanceof AbstractString) {
            $string = $string->string;
        } elseif (!\is_string($string)) {
            return parent::equalsTo($string);
        }

        if ('' !== $string && $this->ignoreCase) {

return null;
        }

        $tail = \DIRECTORY_SEPARATOR.implode(\DIRECTORY_SEPARATOR, $tail);
        $tailLen = \strlen($tail);
        $real = $refl->getFileName();

        if (2 === self::$caseCheck) {
            $real = $this->darwinRealpath($real);
        }

        if (0 === substr_compare($real, $tail, -$tailLen, $tailLen, true)
            && 0 !== substr_compare($real, $tail, -$tailLen, $tailLen, false)
        ) {
            return [substr($tail, -$tailLen + 1), substr($real, -$tailLen + 1), substr($real, 0, -$tailLen + 1)];
        }

        return null;
    }

    /** * `realpath` on MacOSX doesn't normalize the case of characters. */

public static function getVersionNumber(\DOMDocument $dom): string
    {
        /** @var \DOMNode $xliff */
        foreach ($dom->getElementsByTagName('xliff') as $xliff) {
            $version = $xliff->attributes->getNamedItem('version');
            if ($version) {
                return $version->nodeValue;
            }

            $namespace = $xliff->attributes->getNamedItem('xmlns');
            if ($namespace) {
                if (0 !== substr_compare('urn:oasis:names:tc:xliff:document:', $namespace->nodeValue, 0, 34)) {
                    throw new InvalidArgumentException(sprintf('Not a valid XLIFF namespace "%s".', $namespace));
                }

                return substr($namespace, 34);
            }
        }

        // Falls back to v1.2         return '1.2';
    }

return null;
        }

        $message = $error->getMessage();
        $messageLen = \strlen($message);
        $notFoundSuffix = '()';
        $notFoundSuffixLen = \strlen($notFoundSuffix);
        if ($notFoundSuffixLen > $messageLen) {
            return null;
        }

        if (0 !== substr_compare($message, $notFoundSuffix, -$notFoundSuffixLen)) {
            return null;
        }

        $prefix = 'Call to undefined function ';
        $prefixLen = \strlen($prefix);
        if (!str_starts_with($message, $prefix)) {
            return null;
        }

        $fullyQualifiedFunctionName = substr($message, $prefixLen, -$notFoundSuffixLen);
        if (false !== $namespaceSeparatorIndex = strrpos($fullyQualifiedFunctionName, '\\')) {

return clone $this;
        }

        $str = clone $this;

        if ($prefix instanceof self) {
            $prefix = $prefix->string;
        } else {
            $prefix = (string) $prefix;
        }

        if ('' !== $prefix && \strlen($this->string) >= \strlen($prefix) && 0 === substr_compare($this->string, $prefix, 0, \strlen($prefix), $this->ignoreCase)) {
            $str->string = substr($this->string, \strlen($prefix));
        }

        return $str;
    }

    abstract public function trimStart(string $chars = " \t\n\r\0\x0B\x0C\u{A0}\u{FEFF}"): static;

    /** * @param string|string[] $suffix */

$locale = $catalogue->getLocale();
            } else {
                break;
            }
        }

        $parameters = array_map(fn ($parameter) => $parameter instanceof TranslatableInterface ? $parameter->trans($this, $locale) : $parameter, $parameters);

        $len = \strlen(MessageCatalogue::INTL_DOMAIN_SUFFIX);
        if ($this->hasIntlFormatter
            && ($catalogue->defines($id, $domain.MessageCatalogue::INTL_DOMAIN_SUFFIX)
            || (\strlen($domain) > $len && 0 === substr_compare($domain, MessageCatalogue::INTL_DOMAIN_SUFFIX, -$len, $len)))
        ) {
            return $this->formatter->formatIntl($catalogue->get($id, $domain), $locale, $parameters);
        }

        return $this->formatter->format($catalogue->get($id, $domain), $locale, $parameters);
    }

    public function getCatalogue(string $locale = null): MessageCatalogueInterface
    {
        if (!$locale) {
            $locale = $this->getLocale();
        }

return $chunks;
    }

    public function endsWith(string|iterable|AbstractString $suffix): bool
    {
        if ($suffix instanceof AbstractString) {
            $suffix = $suffix->string;
        } elseif (!\is_string($suffix)) {
            return parent::endsWith($suffix);
        }

        return '' !== $suffix && \strlen($this->string) >= \strlen($suffix) && 0 === substr_compare($this->string, $suffix, -\strlen($suffix), null, $this->ignoreCase);
    }

    public function equalsTo(string|iterable|AbstractString $string): bool
    {
        if ($string instanceof AbstractString) {
            $string = $string->string;
        } elseif (!\is_string($string)) {
            return parent::equalsTo($string);
        }

        if ('' !== $string && $this->ignoreCase) {