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PHP regular method example to obtain numbers in string

小云云
小云云Original
2018-03-07 10:25:164834browse

This article mainly introduces you to several methods of obtaining numbers in strings using PHP combined with regular expressions. It is very simple and practical. I hope it can help you.

php combines regular expressions to get the numbers in the string

<?php
  $patterns = "/\d+/"; //第一种
  //$patterns = "/\d/";  //第二种
  $strs="left:0px;top:202px;width:90px;height:30px";
  preg_match_all($patterns,$strs,$arr);
  print_r($arr);
    
/***************运行结果*********************/
//第一种
Array
(
  [0] => Array
    (
      [0] => 0
      [1] => 202
      [2] => 90
      [3] => 30
    )
)
//第二种
Array
(
  [0] => Array
    (
      [0] => 0
      [1] => 2
      [2] => 0
      [3] => 2
      [4] => 9
      [5] => 0
      [6] => 3
      [7] => 0
    )
)

php Gets the number in the specified string $a="era happened 123 happened 12345678 happened"; give a The function can capture the number 12345678 in $a. If not, it returns 0.
Write the function well,
1. Only match numbers with a length of 8 bits
2. If found, return the changed number. If not, return 0

   
function a($str){
return preg_match(&#39;/([0-9]{8})/&#39;,$str,$a) ? $a[1] : 0;
}

I searched for this on the Internet and tested it and found that it is ok, but if the character length is not d{4} or a fixed length, it will not work

function findNum($str=&#39;&#39;){
 if(empty($str)){return &#39;&#39;;}
 $reg=&#39;/(\d{4}(\.\d+)?)/is&#39;;//匹配数字的正则表达式
 preg_match_all($reg,$str,$result);
 if(is_array($result)&&!empty($result)&&!empty($result[1])&&!empty($result[1][0])){
 return $result[1][0];
 }
 return &#39;&#39;;
}

Later I found out that there is A

$str=trim($str);
 if (preg_match(&#39;|(\d+)|&#39;,$str,$r)) return $r[1];

discovered that this can get numbers of any continuous length. Of course, I saw a lot of them on the Internet, but there was one that worked, so I didn’t test it again.

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