chr()
(PHP 4, PHP 5, PHP 7)
返回指定的字符
说明
chr( int $ascii) : string
返回相对应于$ascii所指定的单个字符。
此函数与ord()是互补的。
参数
- $ascii
Ascii 码。
返回值
返回规定的字符。
范例
Example #1chr()例子
<?php $str = "The string ends in escape: "; $str .= chr(27); /* 在 $str 后边增加换码符 */ /* 通常这样更有用 */ $str = sprintf("The string ends in escape: %c", 27); ?>
参见
Note that if the number is higher than 256, it will return the number mod 256. For example : chr(321)=A because A=65(256)
Another quick and short function to get unicode char by its code. <?php /** * Return unicode char by its code * * @param int $u * @return char */ function unichr($u) { return mb_convert_encoding('&#' . intval($u) . ';', 'UTF-8', 'HTML-ENTITIES'); } ?>
I spent hours looking for a function which would take a numeric HTML entity value and output the appropriate UTF-8 bytes. I found this at another site and only had to modify it slightly; so I don't take credit for this. <?php function unichr($dec) { if ($dec < 128) { $utf = chr($dec); } else if ($dec < 2048) { $utf = chr(192 + (($dec - ($dec % 64)) / 64)); $utf .= chr(128 + ($dec % 64)); } else { $utf = chr(224 + (($dec - ($dec % 4096)) / 4096)); $utf .= chr(128 + ((($dec % 4096) - ($dec % 64)) / 64)); $utf .= chr(128 + ($dec % 64)); } return $utf; } ?> So for example: <?php $str = "Chinese: 中文"; $str = preg_replace("/&#(\d{2,5});/e", "unichr($1);", $str); ?>
Here is a function that's help me find what chr(number) outputs what character quicker than typing out 256 echo tags. <?php function listChr(){ for ($i = 0; $i < 256; ++$i) { static $genNum; $genNum++; echo "chr($genNum) will output '"; echo (chr($genNum)); echo "'< br>\n"; } } listChr(); ?> Another helpful chr is #9, being a tab. Quite using when making error logs. $tab = (chr(9)); echo "<pre>error{$tab}date{$tab}time</pre>"; -- HappyEvil
chr() with unicode support <?php function uchr ($codes) { if (is_scalar($codes)) $codes= func_get_args(); $str= ''; foreach ($codes as $code) $str.= html_entity_decode('&#'.$code.';',ENT_NOQUOTES,'UTF-8'); return $str; } echo uchr(23383); echo '<br/>'; echo uchr(23383,215,23383); echo '<br/>'; echo uchr(array(23383,215,23383,215,23383)); echo '<br/>'; ?>
argument is automatically converted to integer, so chr('65') and chr(65) would both output the letter A
to remove the ASCII control characters (except "line feed" and "tab") : $tab_chr = array() ; for($control = 0; $control < 32; $control++) { if ($control != 9 && $control != 10) { $tab_chr[]= chr($control) ; } } $tab_chr[]= chr(127) ; $string = str_replace($tab_chr, '', $string);
In addition to replacing Microsoft Windows smart quotes, as sgaston demonstrated on 2006-02-13, I replace all other Microsoft Windows characters using suggestions[1] published by character code specialist[2] Jukka Korpela. <?php $str = str_replace(chr(130), ',', $str); // baseline single quote $str = str_replace(chr(131), 'NLG', $str); // florin $str = str_replace(chr(132), '"', $str); // baseline double quote $str = str_replace(chr(133), '...', $str); // ellipsis $str = str_replace(chr(134), '**', $str); // dagger (a second footnote) $str = str_replace(chr(135), '***', $str); // double dagger (a third footnote) $str = str_replace(chr(136), '^', $str); // circumflex accent $str = str_replace(chr(137), 'o/oo', $str); // permile $str = str_replace(chr(138), 'Sh', $str); // S Hacek $str = str_replace(chr(139), '<', $str); // left single guillemet $str = str_replace(chr(140), 'OE', $str); // OE ligature $str = str_replace(chr(145), "'", $str); // left single quote $str = str_replace(chr(146), "'", $str); // right single quote $str = str_replace(chr(147), '"', $str); // left double quote $str = str_replace(chr(148), '"', $str); // right double quote $str = str_replace(chr(149), '-', $str); // bullet $str = str_replace(chr(150), '-', $str); // endash $str = str_replace(chr(151), '--', $str); // emdash $str = str_replace(chr(152), '~', $str); // tilde accent $str = str_replace(chr(153), '(TM)', $str); // trademark ligature $str = str_replace(chr(154), 'sh', $str); // s Hacek $str = str_replace(chr(155), '>', $str); // right single guillemet $str = str_replace(chr(156), 'oe', $str); // oe ligature $str = str_replace(chr(159), 'Y', $str); // Y Dieresis ?> [1] On the use of some MS Windows characters in HTML http://www.cs.tut.fi/~jkorpela/www/windows-chars.html [2] Unicode Explained by Jukka Korpela http://www.amazon.com/dp/059610121X/
Want terminal colors in command line php scripts? This should take care of that. <? $_colors = array( 'LIGHT_RED' => "[1;31m", 'LIGHT_GREEN' => "[1;32m", 'YELLOW' => "[1;33m", 'LIGHT_BLUE' => "[1;34m", 'MAGENTA' => "[1;35m", 'LIGHT_CYAN' => "[1;36m", 'WHITE' => "[1;37m", 'NORMAL' => "[0m", 'BLACK' => "[0;30m", 'RED' => "[0;31m", 'GREEN' => "[0;32m", 'BROWN' => "[0;33m", 'BLUE' => "[0;34m", 'CYAN' => "[0;36m", 'BOLD' => "[1m", 'UNDERSCORE' => "[4m", 'REVERSE' => "[7m", ); function termcolored($text, $color="NORMAL", $back=1){ global $_colors; $out = $_colors["$color"]; if($out == ""){ $out = "[0m"; } if($back){ return chr(27)."$out$text".chr(27).chr(27)."[0m".chr(27); }else{ echo chr(27)."$out$text".chr(27).chr(27)."[0m".chr(27); }//fi }// end function echo termcolored("test\n", "BLUE"); ?>
[Editor's note: %c is defined as: "Print the character belonging to the ascii code given" chr() just gives a string, so you need to use %s, even if the string consists of only one character. This is consistent with other languages. --Jeroen@php.net] Learn from my mistake: Do not expect this to work! <?php $c_question = chr(63); $v_out = sprintf("<%cphp\n", $c_question); //... more stuff being sprintf'd into v_out here ... $v_out = sprintf("%s%c>\n", $v_out, $c_question); $v_fp = fopen("foofile", "w"); if ($v_fp) { fwrite($v_fp, $v_out, strlen($v_out)); fclose($v_fp); } ?> When I did this, foofile contained <NUL NUL NUL NUL NUL>. I spun my wheels quite awhile looking at fputs, fwrite to verify I was calling those functions correctly. My mistake was using $c_question = chr(63) instead of $c_question = 63 (correct). Then everything worked fine.
Simple password generation function using sprintf and the %c type specifier; which is the same as chr(). function genPass($len = 8) { for ($i=0;$i<=$len;$i++) { $passwd = sprintf('%s%c', isset($passwd) ? $passwd : NULL, rand(48, 122)); } return $passwd; }
Note that chr(10) is a 'line feed' and chr(13) is a 'carriage return' and they are not the same thing! I found this out while attempting to parse text from forms and text files for inclusion as HTML by replacing all the carriage returns with <BR>'s only to find after many head-scratchings that I should have been looking for line feeds. If anyone can shed some light on what the difference is, please do. If you're planning on saving text from a form into a database for later display, you'll need to apply the following function so that it gets saved with the proper HTML tags. <?php $text = str_replace ( chr(10), "<BR>", $text ); ?> When you want to plug it back into that form for editing you need to convert it back. <?php $text = str_replace ( "<BR>", chr(10), $text) ?> Hope this saves somebody some trouble. :)
I needed to generate an invalid UTF-8 character for testing with JSON. This did the trick: <?php echo 'Bogus UTF-8 character at end' . chr(0xC6) ;
string mb_chr ( int $cp [, string $encoding ] ) Parameter List: cp - character code (in decimal notation) encoding - encoding (UTF-8, ASCII and so on) We get the letter 'Ж' from the encoding UTF-8: $sim = mb_chr(0x0416, 'UTF-8'); echo $sim; // Ж Get the character '}' from the encoding ASCII: $sim = mb_chr(125, 'ASCII'); echo $sim ; // }
// rivencodec 1.0 // encode riverse ascii 1 simple function can encode/decode // can use it for secure source with speed encode text <?php function rivencodec($ch,$a=0) { while((@$b = $ch[$a++])) { $ch[$a-1] = chr(255-ord($b)); } return $ch; } $zz = rivencodec("abcdefghijklmn"); echo 'encode: ',$zz,'<br/>',PHP_EOL; $yy = rivencodec($zz); echo 'decode: ',$yy,'<br/>',PHP_EOL; ?>
Here is a sample of encoding and decoding using "chr" and "ord". <?php function Encode($txtData,$Level){ for ($j = 0;$j<$Level;$j++){ $tmpStr = ''; for ($i = 0;$i<strlen($txtData);$i++) $tmpStr .= ord(substr(strtoupper($txtData), $i, 1)); $txtData = $tmpStr; } return (strlen($Level)).$Level.$txtData; } function Decode($txtData){ $intLevel = substr($txtData, 1, substr($txtData, 0, 1)); $startStr = substr($txtData, substr($txtData, 0, 1)+1, strlen($txtData)); for ($j = 0;$j<$intLevel;$j++){ for ($i = 0;$i<strlen($startStr);$i+=2) $tmpStr .= chr(intval(substr($startStr, $i, 2))); $startStr = $tmpStr; $tmpStr = ""; } return $startStr; } echo Encode('123',4).'<br>'; echo Decode(Encode('123',5)); ?>
The function chr() also accepts negative numbers as an ascii code, so chr(-number) is equal to chr((number%256)+256). And for ascii code higher than 255 is chr(number%256) We can test with a little script <?php for($i=-300; $i<300; $i++){ echo "Ascii $i\t" . ord(chr($i)) . "\n"; } ?>
I was looking for a simple method to construct excel like column identifiers e.g: A B .... AA AB AC etc, using chr() and modulo, but there is magic... https://www.php.net/manual/en/language.operators.increment.php So, this also works <?php $p = chr(65); // or simply $p = 'A'; for ($i = 1; $i < 53; $i++){ echo $p++ . " - "; if ($i % 10 == 0) echo '</br>'; } ?> Gives A - B - C - D - E - F - G - H - I - J - K - L - M - N - O - P - Q - R - S - T - U - V - W - X - Y - Z - AA - AB - AC - AD - AE - AF - AG - AH - AI - AJ - AK - AL - AM - AN - AO - AP - AQ - AR - AS - AT - AU - AV - AW - AX - AY - AZ -
Secure password generator with a variable maximum amount of symbols. <?php function passwdGen($minLength = 8, $maxLength = 12, $maxSymbols = 2) { $symbolCount = 0; srand((double)microtime() * 1000003); for ($i = 0; $i < rand($minLength, $maxLength); $i++) { do { $char = rand(33, 126); $symbolCount += $isSymbol = (!in_array($char, range(48, 57)) && !in_array($char, range(65, 90)) && !in_array($char, range(97, 122))); if ($symbolCount <= $maxSymbols || !$isSymbol) { break; } } while (true); $passwd = sprintf('%s%c', isset($passwd) ? $passwd : NULL, $char); } return $passwd; } ?>
When having to deal with parsing an IIS4 or IIS5 metabase dump I wrote a simple function for converting those MS hexidecimal values into their ascii counter parts. Hopefully someone will find use for it. <?php function hex_decode($string) { for ($i=0; $i < strlen($string); $i) { $decoded .= chr(hexdec(substr($string,$i,2))); $i = (float)($i)+2; } return $decoded; } ?>
Another quick function to get unicode char by its code. <?php function unichr($dec) { if ($dec < 0x80) { $utf = chr($dec); } else if ($dec < 0x0800) { $utf = chr(0xC0 + ($dec >> 6)); $utf .= chr(0x80 + ($dec & 0x3f)); } else if ($dec < 0x010000) { $utf = chr(0xE0 + ($dec >> 12)); $utf .= chr(0x80 + (($dec >> 6) & 0x3f)); $utf .= chr(0x80 + ($dec & 0x3f)); } else if ($dec < 0x200000) { $utf = chr(0xF0 + ($dec >> 18)); $utf .= chr(0x80 + (($dec >> 12) & 0x3f)); $utf .= chr(0x80 + (($dec >> 6) & 0x3f)); $utf .= chr(0x80 + ($dec & 0x3f)); } else { die("UTF-8 character size is more than 4 bytes"); } return $utf; } echo unichr(0x263A); ?>
It seems that php uses the table from here: http://ascii-code.com/ (and not from here: http://www.asciitable.com/ as suggested in the documentation) for codes from 128 to 255. <?php for ($i = 32; $i <= 255; $i++) { echo chr($i); } ?>