$var = 3;
if ($cleanvar = preg_match('/^[0-9]{0,2}$/', $var))
{
echo $cleanvar; echo $var; exit();
}
else
. . .
Strange output. This is causing my cleanvar to echo 1 and var still echo's 3. Why is this happening? The point of this regex is to only match whole numbers, as 1 or 2 digits. e.g.( 1, 2, 4, 38, 24)
Is their an issue in my Regex? Or what is causing this odd behavior?
$cleanvar is just true or false. You're looking for a number between 0 and 2 digits in length (from the beginning to the end of the string, so no other characters are allowed).
EDIT: it returns 1 if matched, 0 if not.
See this for more information: http://us3.php.net/preg_match
$var should be followed by an array if you want it set. You might wish to change to {1,2} if matching >=1.
Your regex is correct, and it is matching correct. Just that preg_match returns 1 if you get a match and 0 if it doesn't. See the documentation.
If you are trying to validate an input value, you only need look at the return of preg_match. Using the + operator matches "one or more of the preceding element."
if (preg_match('/^[0-9]+$/', $var)) {
// we matched a number only, so we know $var is clean
} else {
}
If you need to extract a number from an input field, you can use capture groups:
if (preg_match('/([0-9]+)/', $var, $matches)) {
$num = $matches[1];
} else {
}
Note that this does not match the entire input, but will return on the first number it finds in the input $var.
Related
I have a user-input string with 2 comma-delimited integers.
Example (OK):
3,5
I want to reject any user input that contains leading 0's for either number.
Examples (Bad):
03,5
00005,3
05,003
Now what I could do is separate the two numbers into 2 separate string's and use ltrim on each one, then see if they have changed from before ltrim was executed:
$string = "03,5";
$string_arr = explode(",",$string);
$string_orig1 = $string_arr[0];
$string_orig2 = $string_arr[1];
$string_mod1 = ltrim($string_orig1, '0');
$string_mod2 = ltrim($string_orig2, '0');
if (($string_mod1 !== $string_orig1) || ($string_mod2 !== $string_orig2)){
// One of them had leading zeros!
}
..but this seems unnecessarily verbose. Is there a cleaner way to do this? Perhaps with preg_match?
You could shorten the code and check if the first character of each part is a zero:
$string = "03,5";
$string_arr = explode(",",$string);
if ($string_arr[0][0] === "0" || $string_arr[1][0] === "0") {
echo "not valid";
} else {
echo "valid";
}
Here is one approach using preg_match. We can try matching for the pattern:
\b0\d+
The \b would match either the start of the string, or a preceding comma separator.
If we find such a match, it means that we found one or more numbers in the CSV list (or a single number, if only one number present) which had a leading zero.
$input = "00005,3";
if (preg_match("/\b0\d+/", $input)) {
echo "no match";
}
You can do a simple check that if the first character is 0 (using [0]) or that ,0 exists in the string
if ( $string[0] == "0" || strpos($string, ",0") !== false ) {
// One of them had leading zeros!
}
All the current answers fail if any of the values are simply 0.
You can just convert to integer and back and compare the result.
$arr = explode(',', $input);
foreach($arr as $item) {
if( (str)intval($item) !== $item ) {
oh_noes();
}
}
However I am more curious as to why this check matters at all.
One way would be with /^([1-9]+),(\d+)/; a regex that checks the string starts with one or more non-zero digits, followed by a comma, then one or more digits.
preg_match('/^([1-9]+),(\d+)/', $input_line, $output_array);
This separates the digits into two groups and explicitly avoids leading zeros.
This can be seen on Regex101 here and PHPLiveRegex here.
I have this autogenerated variable:
$var = "WXYZ 300700Z 32011KT 9999 FEW035 SCT200 24/16 Q1007 NOSIG";
How can I search and save "9999" in this var? I cant use substr cause $var's value is always changing and it is always in another "place" in the variable. It is always 4 numbers.
You can match 4 numbers wrapped by word boundaries or space characters, depending on what you need with regular expression (regex/regexp).
if( preg_match('/\b([0-9]{4})\b/', $var, $matches) > 0 ) {
// $matches[1] contains the number
}
Note, however, that the word boundary match will also match on non-letter characters (symbols like dollar sign ($), hyphen (-), period (.), comma (,), etc.). So a string of "XYZ ABC 9843-AB YZV" would match the "9843". If you want to just match based on numbers surrounded by white space (spaces, tabs, etc) you can use:
if( preg_match('/(?:^|\s)([0-9]{4})(?:\s|$)/', $var, $matches) > 0 ) {
// $matches[1] contains the number
}
Using explode is the way to go, we need to turn the string into an array, our variables are separated by white space, so we get a variable every time we face a white space " ", i made another example to understand how explode works.
<?php
$var = "WXYZ 300700Z 32011KT 9999 FEW035 SCT200 24/16 Q1007 NOSIG";
print_r (explode(" ",$var)); //Display the full array.
$var_search = explode(" ",$var);
echo $var_search[3];//To echo the 9999 (4th position).
?>
<br>
<?php
$var = "WXYZ+300700Z+32011KT+9999+FEW035+SCT200+24/16+Q1007+NOSIG";
print_r (explode("+",$var)); //Display the full array.
$var_search = explode("+",$var);
echo $var_search[3];//To echo the 9999 (4th position).
?>
I hop this is what you're looking for
Is this viable?
$var = "WXYZ 300700Z 32011KT 9999 FEW035 SCT200 24/16 Q1007 NOSIG";
if (strpos($var, '9999') == true {
// blah blah
}
else{
echo 'Value not found'
}
Personally haven't tested this yet, but I think you're looking for something along these lines...
Hello I would use a preg_match regex using this regular expression : \d{4}
here is the solution
var str1 = "WXYZ 300700Z 32011KT 9999 FEW035 SCT200 24/16 Q1007 NOSIG";
var str2 = "9999";
if(str1.indexOf(str2) != -1){
console.log(str2 + " found");
}
I have many headlines in my project like:
00.00.2014 - Headline Description e.t.c.
I want to check with php if the given strings contain the format 00.00.0000 - in front. The part after the - doesn't matter.
Can someone help me with something like:
$format = '00.00.0000 -';
if ($string MATCHES $format IN FRONT) {
// ...some code...
}
This should work:
if (preg_match("/^\d{2}\.\d{2}\.\d{4}\s\-\s.*$/", $string) === 1) {
// $string matches!
}
Explanation:
^ is "the beginning of the string"
\d is any digit (0, 1, 2, ..., 9)
{n} means "repeated n times"
\. is a dot
\s is a space
\- is a minus sign
. is "any single character"
* means "repeated 0 or more times`
$ means "end of the string"
I don't have a dev environment to test this out on but i'll give you some psuedocode:
I'm unsure of the context, but you can test this function on any given STRING:
Function:
Boolean hasCorrectFormat($myString){
//Here take the string and cut it into a char array.
$charArray = str_split($myString);
//This will give you a char array. Compare the first 12 elements of this
//array to see if they are correct. If its supposed to be number make
//sure it is, if its supposed to be a "." make sure it is..etc
//"00.00.0000 -" is 12 characters.
if(!isNumeric(charArray[0])){
return false;
}
else if(!isNumeric(charArray[1])){
return false;
}
else if(charArray[2] != "."){
return false;
}
//so on and so forth.....
else {return true}
}
Like i said i can't test this, and i can almost guarantee you this code wont run. This should give you the logic involved though.
Edit: also i wrote this assuming you dont literally mean "00.00.0000" but rather "xx.xx.xxxx" x being any number 0-9. If you need to make sure it is literally zeros then just cut your string to be the first ten chars and compare it.
Use the strpos function. Something like this:
if (strpos($string,'00.00.0000 -') !== true) {
//some code
}
This is to test version numbers. They need to contain only numbers, but can have multiple decimal points.
For example:
$a = '1.2.3';
is_numeric($a) returns false, and floatval($a) strips out the extra decimal sections, without returning a useful answer to the test.
Is there any PHP function that would do this?
You can use preg_match():
if(preg_match('~^([0-9]+(\.[0-9]+)*)$~', $string)) {
echo 'ok';
}
The regex pattern matches from the begin ^ to the end $ of the string and checks if it begins with a number and then contains only numbers - optionally separated by single dots - and ends with a number again.
You can use the strcspn function:
$q='1.2.3';
if (strcspn($q, '0123456789') != strlen($q))
echo "true";
else
echo "false";
I'm trying to port this java to php:
String _value = '1111122222';
if (_value.matches("(1{5}|2{5}|3{5}|4{5}|5{5}|6{5}|7{5}|8{5}|9{5}){2}")) {
// check for number with the same first 5 and last 5 digits
return true;
}
As the comment suggests, I want to test for a string like '1111122222' or '5555566666'
How can I do this in PHP?
Thanks,
Scott
You can use preg_match to do so:
preg_match('/^(1{5}|2{5}|3{5}|4{5}|5{5}|6{5}|7{5}|8{5}|9{5}){2}$/', $_value)
This returns the number of matches (i.e. either 0 or 1) or false if there was an error. Since the String’s matches method returns only true if the whole string matches the given pattern but preg_match doesn’t (a substring suffices), you need to set markers for the start and the end of the string with ^ and $.
You can also use this shorter regular expression:
^(?:(\d)\1{4}){2}$
And if the second sequence of numbers needs to be different from the former, use this:
^(\d)\1{4}(?!\1)(\d)\2{4}$
Well, you could do:
$regex = '/(\d)\1{4}(\d)\2{4}/';
if (preg_match($regex, $value)) {
return true;
}
Which should be much more efficient (and readable) than the regex you posted...
Or, an even shorter (and potentially cleaner) regex:
$regex = '/((\d)\2{4}){2}/';
$f = substr($_value, 0, 5);
$s = substr($_value, -5);
return (substr_count($f, $f[0]) == 5 && substr_count($s, $s[0]) == 5);
Conversion is below. preg_match() is the key: http://www.php.net/preg_match
$value = '1111122222';
if (preg_match('/^(1{5}|2{5}|3{5}|4{5}|5{5}|6{5}|7{5}|8{5}|9{5}){2}$/', $value)) {
// check for number with the same first 5 and last 5 digits
return true;
}