PHP提取字符串中数字的方法
有时候我们在PHP开发中需要在一串字符串中将所有的数字提取出来,研究了一下发现方法还挺多,值得记录一下。
对如何使用PHP将字符串中的数字提取出来的功能做了一个小总结,总结三种方法如下:
1、使用正则表达式:
<span style="font-size: 14px;">function findNum($str=''){</span><br /> $str=trim($str);<br /> if(empty($str)){return '';}<br /> $reg='/(\d{3}(\.\d+)?)/is';//匹配数字的正则表达式<br /> preg_match_all($reg,$str,$result);<br /> if(is_array($result)&&!empty($result)&&!empty($result[1])&&!empty($result[1][0])){<br /> return $result[1][0];<br /> }<br /> return '';<br /><p>}<span style="font-size: 14px;">
2、使用in_array方法:
<span style="font-size: 14px;">function findNum($str=''){</span><br /> $str=trim($str);<br /> if(empty($str)){return '';}<br /> $temp=array('1','2','3','4','5','6','7','8','9','0');<br /> $result='';<br /> for($i=0;$i<strlen($str);$i++){<br /> if(in_array($str[$i],$temp)){<br /> $result.=$str[$i];<br /> }<br /> }<br /> return $result;<br /><p>}<span style="font-size: 14px;">
3、使用is_numeric函数:
<span style="font-size: 14px;">function findNum($str=''){</span><br /> $str=trim($str);<br /> if(empty($str)){return '';}<br /> $result='';<br /> for($i=0;$i<strlen($str);$i++){<br /> if(is_numeric($str[$i])){<br /> $result.=$str[$i];<br /> }<br /> }<br /> return $result;<br />}

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