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ereg
Regular expression match
(PHP 4, PHP 5)
Example 1894. ereg() exampleThe following code snippet takes a date in ISO format (YYYY-MM-DD) and prints it in DD.MM.YYYY format: <?php Related Examples ( Source code ) » ereg Examples ( Source code ) » Login form with Error Messages and Preserving User Input Examples ( Source code ) » Parse http link from string Examples ( Source code ) » Clean Path by Regular Expressions Examples ( Source code ) » Regular Expression validates an email adress Examples ( Source code ) » Email validation with Regular Expressions Examples ( Source code ) » Email validation Demo Examples ( Source code ) » String contains string Examples ( Source code ) » String match for domain name Examples ( Source code ) » String replace with Regular Expressions Examples ( Source code ) » Using popen() to Read the Output of the UNIX who Command Examples ( Source code ) » URL validation by Regular Expression Examples ( Source code ) » Get WhoIs Information for 270 different tld's Examples ( Source code ) » E-mail address validation class Examples ( Source code ) » Extract Email Address from any text Code Examples / Notes » eregjoel weierman
While this is relatively simple example, I was unable find a clean method of doing this anywhere else, so I thought I would post it here. As part of a file upload package, I wanted to prevent the uploading of double byte character filenames and other special ASCII characters that may not work well on a Windows and/or Linux system. Here is the statement I ended up using which seems to have done the trick. ereg("[^a-zA-Z0-9._-]", $file_name) 'morgan'.'galpin'.chr 64 .'gmail'.'.com'
Try this version instead of the one previously posted. <?php /** Returns an array containing each of the sub-strings from text that are between openingMarker and closingMarker. The text from openingMarker and closingMarker are not included in the result. This function does not support nesting of markers. */ function returnSubstrings($text, $openingMarker, $closingMarker) { $openingMarkerLength = strlen($openingMarker); $closingMarkerLength = strlen($closingMarker); $result = array(); $position = 0; while (($position = strpos($text, $openingMarker, $position)) !== false) { $position += $openingMarkerLength; if (($closingMarkerPosition = strpos($text, $closingMarker, $position)) !== false) { $result[] = substr($text, $position, $closingMarkerPosition - $position); $position = $closingMarkerPosition + $closingMarkerLength; } } return $result; } // Example: $exampleText = "<b>bonjour</b> Ã tous, <b>comment</b> allez-vous ?"; $result = returnSubstrings($exampleText, "<b>", "</b>"); var_export($result); // Prints: // array ( // 0 => 'bonjour', // 1 => 'comment', // ) ?> notbald
Save yourself some headache and time, don't use the \d (digits) \w (alphanumeric) and \s (whitespace) short forms. Not only do they make the code less readable, they don't seem to work with ereg. Use [0-9], [A-Za-z0-9], [ \n\r\t] instead. Since the regex example in this article is a bit on the complex side, I'll throw in a simpler regex example: Say you want to validate valid variable names: <?php $regex_valid_variable_name = '^[A-Za-z_][A-Za-z0-9_]*$'; // ^ in this context means that the regex is anchored // to the beginning of the string. // // A single [xxx] means that a single letter must mach // the criteria within // // The [xxx]* means that [xxx] can mach from zero to // unlimited times. // // The $ is another anchor, except it is for the end of // the sting. // Valid names: "_", "hello1", "a_variable" // Invalid names: "4number", "five-to", "one two", " space " //Test it out: $regx = $regx_valid_variable_name; $valid = array ( '_', 'hello1', 'a_variable' ); $invalid = array ( '4number', 'five-to', 'one two', ' space '); foreach($valid as $v) echo 'Valid '.(ereg($regx, $v) ? 'yes' : '<b>no</b>') . ": $v<br />\n"; foreach($invalid as $v) echo 'Invalid '.(!ereg($regx, $v) ? 'yes' : '<b>no</b>') . ": $v<br />\n"; ?> mixailo
preg_match is much more faster then ereg, MUCH MORE faster.
irlkersten
On a small note to email checking: Recently it is possible to register domains like www.küche.de This would also mean that the IsEMail() function from "php at easy2sync dot com" would report an email address like "contact@küche.de" as false. To correct this, use the function below: function IsEMail($e) { if(eregi("^[a-zA-Z0-9]+[_a-zA-Z0-9-]* (\.[_a-z0-9-]+)*@[a-zöäüÖÄÜ0-9]+ (-[a-zöäüÖÄÜ0-9]+)*(\.[a-zöäüÖÄÜ0-9-]+)* (\.[a-z]{2,4})$", $e)) { return TRUE; } return FALSE; } theppg_001
Ok well someone else posted this but if didn't work so I made my own. I used this to check file names that are to be created on a server. File names that start with a-Z or 0-9 and contain a-Z, 0-9, underscore(_), dash(-), and dot(.) will be accepted. File names beginning with anything but a-Z or 0-9 will be rejected. File names containing anything other than above mentioned will also be rejected. Here it is. <?php $result = ereg("(^[a-zA-Z0-9]+([a-zA-Z\_0-9\.-]*))$" , $filename); ?> psonice aat gmail.com
I wanted a more strict check for UK postcodes, and decided to do it by stripping all whitespace then using ereg: <?php $pcode=str_replace(" ","",$in_post_code); if (!ereg('^[a-zA-Z]{1,2}[0-9]{1,2}[a-zA-Z]{0,1}[0-9]{1}[a-zA-Z]{2}$', $pcode)) { return false; } ?> Probably could be improved, as I've just started, but it matches everything listed on the post office spec. ar_cat
I had problem using is_numeric() to verify if user inputs is a number (including optional floating sign and decimals). Instead I found this expression from http://www.regular-expressions.info/floatingpoint.html and modified it for a bit. ^[+-]?[0-9]*\.?[0-9]+$ /* 3.55 true -3.55 true +3.55 true 2456.90 true 34skd false 23. false 2dt6 false */ Note: mine doesn't have the exponent part; for matching number with exponents, visit the site above :) tomas
I could not find a definitive and 100% working function that validates the UK postcodes, so was forced to write one myself. The authoritative source of information is http://www.govtalk.gov.uk/gdsc/html/frames/PostCode.htm which I amended with the new postcode for Tristan da Cunha. Here is the ugly beast (don't wanna see regexp's ever again): <?php function IsPostcode($postcode) { $postcode = strtoupper(str_replace(chr(32),'',$postcode)); if(ereg("^(GIR0AA)|(TDCU1ZZ)|((([A-PR-UWYZ][0-9][0-9]?)|" ."(([A-PR-UWYZ][A-HK-Y]][0-9][0-9]?)|" ."(([A-PR-UWYZ][0-9][A-HJKSTUW])|" ."([A-PR-UWYZ][A-HK-Y][0-9][ABEHMNPRVWXY]))))" ."[0-9][ABD-HJLNP-UW-Z]{2})$", $postcode)) return $postcode; else return FALSE; } ?> info
Here's a function i've created to return an array of each substring searched in a string. <? function Return_Substrings($text, $sopener, $scloser) { $result = array(); $noresult = substr_count($text, $sopener); $ncresult = substr_count($text, $scloser); if ($noresult < $ncresult) $nresult = $noresult; else $nresult = $ncresult; unset($noresult); unset($ncresult); for ($i=0;$i<$nresult;$i++) { $pos = strpos($text, $sopener) + strlen($sopener); $text = substr($text, $pos, strlen($text)); $pos = strpos($text, $scloser); $result[] = substr($text, 0, $pos); $text = substr($text, $pos + strlen($scloser), strlen($text)); } return $result; } ?> Example : <? $string = "<b>bonjour</b> Ã tous, <b>comment</b> allez-vous ?"; $result = Return_Substrings($string, "<b>", "</b>"); ?> ben
Here is a tutorial on regular expressions in PHP, which I needed to create ereg functions not covered in the snippets: http://www.zend.com/zend/spotlight/code-gallery-wade5.php jaik
Here is a fixed version of the UK postcode check function by tomas at phusis dot co dot uk. There was a bug on line 2 of the reg expression where a closing square-bracket was doubled-up ("]]" which should've been "]"). <?php function IsPostcode($postcode) { $postcode = strtoupper(str_replace(chr(32),'',$postcode)); if(ereg("^(GIR0AA)|(TDCU1ZZ)|((([A-PR-UWYZ][0-9][0-9]?)|" ."(([A-PR-UWYZ][A-HK-Y][0-9][0-9]?)|" ."(([A-PR-UWYZ][0-9][A-HJKSTUW])|" ."([A-PR-UWYZ][A-HK-Y][0-9][ABEHMNPRVWXY]))))" ."[0-9][ABD-HJLNP-UW-Z]{2})$", $postcode)) return $postcode; else return FALSE; } ?> net_navard
Hello I think this is not clear: "the matches will be stored in the elements of the array regs. $regs[1] will contain the substring which starts at the first left parenthesis; $regs[2] will contain the substring starting at the second, and so on. $regs[0] will contain a copy of the complete string matched. " Beacause By "substring," it means the string contained within the parenthesis. But in that statement it isn't so clearly With regards Amir Hossein Estakhrian puremango dot co dot uk
for constructing regexes, I recommend http://www.weitz.de/regex-coach/ -it highlights the match as you type it!!! php
After a lot of hard work I managed to create the following regular expression, which matches any HTML tag pair (i.e. opening and closing tag), as specified by tagname: ^(.*)(<[ \n\r\t]*tagname(>|[^>]*>))(.*)(<[ \n\r\t]*/[ \n\r\t]*tagname(>|[^>]*>))(.*)$ The expression is deliberately very forgiving of bad HTML - I wanted to match anything that could be reasonably accepted by a forgiving browser, rather than make it standards compliant. Whitespace is allowed between the tagname and the opening and closing tag symbols, and also between the / and the tagname for the closing tag. For my own use, I have wrapped it in a function call, which you may find useful. Here it is with a few notes. I hope somebody finds it useful. - Mark Clements <?php function ereg_MatchedHTMLTags($tagname) { return "^(.*)(<[ \\n\\r\\t]*$tagname(>|[^>]*>))(.*)(<[ \\n\\r\\t]*/[ \\n\\r\\t]*$tagname(>|[^>]*>))(.*)$"; } // Use with eregi to ensure case-insensitive match. // e.g. to split an HTML page based on body tag: // eregi(ereg_MatchedHTMLTags('body'), $Source, $Matches) // The following values will be held in $Matches //(marked values are unintended byproducts of the expression) // *[0] - the entire string ($Source). // [1] - everything before the opening tag // [2] - the opening tag, including all contents (i.e. everything between < and >) // *[3] - the opening tag from end of the tag name, // e.g. '<body bgcolor="#000000">' gives ' bgcolor="#000000">' // [4] - the tag contents (everything between the opening and closing tag) // [5] - the complete closing tag. // *[6] - the closing tag from the end of the tag name // e.g. '</body invalid text>' gives ' invalid text>' // [7] - everything after the closing tag. ?> jason smart knarlin
A common mistake seems to be trying to escape characters within a bracket expression. Unlike the preg functions, backslash is always taken literally within a bracket expression using the ereg functions. See http://php.planetmirror.com/manual/en/function.eregi.php#57824 for more details. Some of the posts here can be re-written to be much simpler. 16-Feb-2005 10:02 attempts to allow square brackets in a string with ^[a-zA-Z0-9 [.[.] [.].] ]{1,}$ Although this appears to work a less confusing means is ^[]a-zA-Z0-9[]{1,}$ The ] has to be the first character (after a possible ^) but the [ can be anywhere as long as it is not in the middle of a range of course. 09-Apr-2005 11:52 Says that ereg("hi[:space:]*bob", $string) doesnt work in php 4 and to use preg_match() instead. The above quoted use is incorrect it should be <?php ereg("hi[[:space:]]*bob", $string); ?> I tested this with the following in php 4.3.3 and it works fine <?php //The hex codes are space, tab, line feed, vertical tab, form feed, carriage return $whitespace = "\x20\x09\x0a\x0b\x0C\x0d"; $teststring = "hi".$whitespace."bob"; $result = ereg ("hi[[:space:]]*bob", $teststring, $arr); echo ('Matches '.$result.' characters'); //Prints Matches 11 characters ?> 23-May-2005 08:22 Says that ereg("^[' A-Za-Z]+$", $cardName); will not work. The fault with the above is the range a-Z the capital Z comes before small a and so this will fail. The following works fine <?php $cardname = "John 'Doe'"; $result = ereg("^[' A-Za-z]+$", $cardname, $arr); echo ('Matches '.$result.' characters'); //Prints Matches 10 characters ?> 09-Sep-2005 11:01 Tries to escape with \ in a bracket expression You cannot with ereg functions (preg you can) so ereg("^([-a-zA-Z0-9_\.\!@#\$&\*\+\=\|])*$" , $var) should be <?php ereg("^([-a-zA-Z0-9_.!@#$&*+=|])*$", $var); ?> |