str_repeat - PHP code example

The PHP Function Str_Repeat

PHP has a built-in function called str_repeat that helps you repeat a string a fixed number of times. It takes a string and an integer as arguments, and returns a new string that is created by repeating the original string a certain number of times.

The str_repeat() function is useful in many scenarios, from generating patterns to creating borders or padding. It’s important for PHP developers to understand the syntax, parameters, and return value of this function so they can use it effectively.

In this article, we’ll walk you through the php function str_repeat and give you some examples to help you understand its usage and functionality. We’ll also cover some tips that can help you improve your code when using this function.

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The str_repeat() function in php is used to repeat a string a fixed number of time. It takes a string and an integer (multiplier) as arguments, and returns a new string. The string parameter is required, and the multiplier must be greater than or equal to 0 in order for the function to work.

The following example shows how to use the str_repeat() function in a simple script. The script will repeat the string 'Hello World' three times. You can copy and paste this code into your coding editor of choice. Then, press the “Run” button at the bottom of the screen to run the code and see the result in your browser.

str_repeat example

// runes.       'ᚠᛇᚻ᛫ᛒᛦᚦ'                => ['Valid UTF8 username', 'assertNull'],
      ' foo'                   => ['Invalid username that starts with a space', 'assertNotNull'],
      'foo '                   => ['Invalid username that ends with a space', 'assertNotNull'],
      'foo bar'               => ['Invalid username that contains 2 spaces \'  \'', 'assertNotNull'],
      ''                       => ['Invalid empty username', 'assertNotNull'],
      'foo/'                   => ['Invalid username containing invalid chars', 'assertNotNull'],
      // NULL.       'foo' . chr(0) . 'bar'   => ['Invalid username containing chr(0)', 'assertNotNull'],
      // CR.       'foo' . chr(13) . 'bar'  => ['Invalid username containing chr(13)', 'assertNotNull'],
      str_repeat('x', UserInterface::USERNAME_MAX_LENGTH + 1) => ['Invalid excessively long username', 'assertNotNull'],
    ];
    // cSpell:enable     foreach ($test_cases as $name => $test_case) {
      [$description, $test] = $test_case;
      $result = user_validate_name($name);
      $this->$test($result, $description . ' (' . $name . ')');
    }
  }

  /** * Runs entity validation checks. */

public static function getValidMultilevelDomains()
    {
        return [
            ['symfony.com'],
            ['example.co.uk'],
            ['example.fr'],
            ['example.com'],
            ['xn--diseolatinoamericano-66b.com'],
            ['xn--ggle-0nda.com'],
            ['www.xn--simulateur-prt-2kb.fr'],
            [sprintf('%s.com', str_repeat('a', 20))],
        ];
    }

    /** * @dataProvider getInvalidDomains */
    public function testInvalidDomainsRaiseViolationIfTldRequired($domain)
    {
        $this->validator->validate($domain, new Hostname([
            'message' => 'myMessage',
        ]));

foreach ($this->attributes as $name => $value) {
            $attributes[] = sprintf('%s: %s', $name, str_replace("\n", '', var_export($value, true)));
        }

        $repr = [static::class.'('.implode(', ', $attributes)];

        if (\count($this->nodes)) {
            foreach ($this->nodes as $name => $node) {
                $len = \strlen($name) + 4;
                $noderepr = [];
                foreach (explode("\n", (string) $node) as $line) {
                    $noderepr[] = str_repeat(' ', $len).$line;
                }

                $repr[] = sprintf(' %s: %s', $name, ltrim(implode("\n", $noderepr)));
            }

            $repr[] = ')';
        } else {
            $repr[0] .= ')';
        }

        return implode("\n", $repr);
    }

'text' => 'header text',
            ],
            'block_id' => 'header_id',
        ], $header->toArray());
    }

    public function testThrowsWhenTextExceedsCharacterLimit()
    {
        $this->expectException(LengthException::class);
        $this->expectExceptionMessage('Maximum length for the text is 150 characters.');

        new SlackHeaderBlock(str_repeat('h', 151));
    }

    public function testThrowsWhenBlockIdExceedsCharacterLimit()
    {
        $this->expectException(LengthException::class);
        $this->expectExceptionMessage('Maximum length for the block id is 255 characters.');

        $header = new SlackHeaderBlock('header');
        $header->id(str_repeat('h', 256));
    }
}

                $c2++;
            }
            // ::             if ($c1 === -1 && $c2 === -1)
            {
                $ip = '0:0:0:0:0:0:0:0';
            }
            // ::xxx             else if ($c1 === -1)
            {
                $fill = str_repeat('0:', 7 - $c2);
                $ip = str_replace('::', $fill, $ip);
            }
            // xxx::             else if ($c2 === -1)
            {
                $fill = str_repeat(':0', 7 - $c1);
                $ip = str_replace('::', $fill, $ip);
            }
            // xxx::xxx             else
            {

if ('cli' !== \PHP_SAPI) {
    throw new Exception('This script must be run from the command line.');
}

define('LINE_WIDTH', 75);

define('LINE', str_repeat('-', LINE_WIDTH)."\n");

function bailout(string $message)
{
    echo wordwrap($message, LINE_WIDTH)." Aborting.\n";

    exit(1);
}

/** * @return string */

$this->expectException(LengthException::class);
        $this->expectExceptionMessage('The sender length of a TurboSMS message must not exceed 20 characters.');

        $message = new SmsMessage('380931234567', 'Hello!');
        $transport = new TurboSmsTransport('authToken', 'abcdefghijklmnopqrstu', $this->createMock(HttpClientInterface::class));

        $transport->send($message);
    }

    public function testInvalidSubjectWithLatinSymbols()
    {
        $message = new SmsMessage('380931234567', str_repeat('z', 1522));
        $transport = new TurboSmsTransport('authToken', 'sender', $this->createMock(HttpClientInterface::class));

        $this->expectException(LengthException::class);
        $this->expectExceptionMessage('The subject length for "latin" symbols of a TurboSMS message must not exceed 1521 characters.');

        $transport->send($message);
    }

    public function testInvalidSubjectWithCyrillicSymbols()
    {
        $message = new SmsMessage('380931234567', str_repeat('z', 661).'Й');

    if (empty($fill) || !\is_scalar($fill)) {
        $fill = ' ';
    }
    if (empty($width) || !is_numeric($width)) {
        $width = 10;
    } else {
        $width = (int) $width;
    }
    // if no string is given, just build one string containing the fill pattern     if (!\is_scalar($str)) {
        return str_repeat($fill, $width);
    }
    // If the string longer than the given width shorten the string and append the break pattern     if (\strlen($str) > $width) {
        $str = substr($str, 0, $width - \strlen($break)) . $break;
    }
    // If the string is shorter than the given width - fill the remaining space with the filling pattern     if ($width > \strlen($str)) {
        return str_repeat($fill, $width - \strlen($str)) . $str;
    }

    return $str;
}

        $string = '';
        for ($x = 0; $x < 200; ++$x) {
            $char = 'a';
            $string .= $char;
        }
        $encoder = new Rfc2231Encoder();
        $encoded = $encoder->encodeString($string, 'utf-8', 0, 75);

        // 72 here and not 75 as we read 4 chars at a time         $this->assertEquals(
            str_repeat('a', 72)."\r\n".
            str_repeat('a', 72)."\r\n".
            str_repeat('a', 56),
            $encoded,
            'Lines should be wrapped at each 72 characters'
        );
    }

    public function testFirstLineCanHaveShorterLength()
    {
        $string = '';
        for ($x = 0; $x < 200; ++$x) {

/** * @return string[] */
    protected function formatChoiceQuestionChoices(ChoiceQuestion $question, string $tag): array
    {
        $messages = [];

        $maxWidth = max(array_map([__CLASS__, 'width'], array_keys($choices = $question->getChoices())));

        foreach ($choices as $key => $value) {
            $padding = str_repeat(' ', $maxWidth - self::width($key));

            $messages[] = sprintf(" [<$tag>%s$padding</$tag>] %s", $key, $value);
        }

        return $messages;
    }

    /** * Outputs an error message. * * @return void */

    private function writeIntVector($file, array $value, int $indentation): void
    {
        fwrite($file, ":intvector{\n");

        foreach ($value as $int) {
            fprintf($file, "%s%d,\n", str_repeat(' ', $indentation + 1), $int);
        }

        fprintf($file, '%s}', str_repeat(' ', $indentation));
    }

    /** * Writes a "string" node. * * @param resource $file The file handle to write to * * @see http://source.icu-project.org/repos/icu/icuhtml/trunk/design/bnf_rb.txt */

    public function start_lvl( &$output, $depth = 0, $args = null ) {
        $indent  = str_repeat( "\t", $depth );
        $output .= "\n$indent<ul class='children'>\n";
    }

    /** * Ends the list of after the elements are added. * * @see Walker_Nav_Menu::end_lvl() * * @since 3.0.0 * * @param string $output Used to append additional content (passed by reference). * @param int $depth Depth of page. Used for padding. * @param stdClass $args Not used. */

if (is_object($value)) {
            if (!in_array('__toString', get_class_methods($value))) {
                $value = get_class($value) . ' object';
            } else {
                $value = $value->__toString();
            }
        } else {
            $value = implode((array) $value);
        }

        if ($this->getObscureValue()) {
            $value = str_repeat('*', strlen($value));
        }

        $message = str_replace('%value%', $value, $message);
        foreach ($this->_messageVariables as $ident => $property) {
            $message = str_replace(
                "%$ident%",
                implode(' ', (array) $this->$property),
                $message
            );
        }

$info['ogg']['pageheader'][$oggpageinfo['page_seqno']] = $oggpageinfo;

                    $VorbisCommentPage++;

                    // First, save what we haven't read yet                     $AsYetUnusedData = substr($commentdata, $commentdataoffset);

                    // Then take that data off the end                     $commentdata     = substr($commentdata, 0, $commentdataoffset);

                    // Add [headerlength] bytes of dummy data for the Ogg Page Header, just to keep absolute offsets correct                     $commentdata .= str_repeat("\x00", 27 + $info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['page_segments']);
                    $commentdataoffset += (27 + $info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['page_segments']);

                    // Finally, stick the unused data back on the end                     $commentdata .= $AsYetUnusedData;

                    //$commentdata .= $this->fread($info['ogg']['pageheader'][$oggpageinfo['page_seqno']]['page_length']);                     $commentdata .= $this->fread($this->OggPageSegmentLength($info['ogg']['pageheader'][$VorbisCommentPage], 1));
                }

            }
            $ThisFileInfo_ogg_comments_raw[$i]['size'] = getid3_lib::LittleEndian2Int(substr($commentdata, $commentdataoffset, 4));

\FFI::memcpy($pointer, $actualMessage, \strlen($actualMessage));

        $this->assertDumpEquals(<<<'PHP' FFI\CData<char*> size 8 align 8 { cdata: "Hello World!\x00" } PHP, $pointer);
    }

    public function testCastCuttedPointerToChar()
    {
        $actualMessage = str_repeat('Hello World!', 30)."\0";
        $actualLength = \strlen($actualMessage);

        $expectedMessage = 'Hello World!Hello World!Hello World!Hello World!'
            .'Hello World!Hello World!Hello World!Hello World!Hello World!Hel'
            .'lo World!Hello World!Hello World!Hello World!Hello World!Hello '
            .'World!Hello World!Hello World!Hello World!Hello World!Hello Wor'
            .'ld!Hello World!Hel';

        $string = \FFI::cdef()->new('char['.$actualLength.']');
        $pointer = \FFI::addr($string[0]);
        \FFI::memcpy($pointer, $actualMessage, $actualLength);