从查询正则表达式中提取值

Question

我需要提取条件（WHERE）的值并执行正则表达式，但我无法正确获取值。

//Patherns
$regex  = "/([a-zA-Z_]+)\s([\<\=\>\s]{0,4})\s+(\".*\")/";

//values ​​to be extracted
$string = 'idCidade >= "bla" OR idEstado="2" and idPais="3"'; 

//regex function
preg_match_all(
    $regex,
    $string,
    $output
);

//displays the result
echo '<pre>';print_r($output);



//incorrect output
Array
(
   [0] => Array
    (
        [0] => idCidade >= "bla" OR idEstado="2" and idPais="3"
    )

   [1] => Array
    (
        [0] => idCidade 
    )

   [2] => Array
    (
        [0] => >= 
    )

   [3] => Array
    (
        [0] => "bla" OR idEstado="2" and idPais="3"
    )
)

我需要正则表达式将值导出到这样的数组；

//correct output
Array
(
   [0] => Array
    (
        [0] => idCidade >= "bla" OR idEstado="2" and idPais="3"
    )

   [1] => Array
    (
        [0] => idCidade
        [1] => idEstado
        [2] => idPais
    )

   [2] => Array
    (
        [0] => >=
        [1] => =
        [2] => =
    )

   [3] => Array
    (
        [0] => "bla"
        [1] => "2"
        [2] => "3"
    )
   [4] => Array
    (
        [0] => "OR"
        [1] => "AND"
        [2] => ""
    )
)

Answer 1

您的错误可能是 .* 匹配太多。您需要通过附加问号使其“不贪婪”： .*?

不过，我建议使用此正则表达式：

'/(OR|AND)?\s*(\w+)\s*([<=>!]+)\s*("[^"]*"|\'[^\']*\'|\d+)/i'

这首先匹配布尔连接器，并且可选，以便您得到：

[1] => Array
    (
        [0] => 
        [1] => OR
        [2] => and
    )

[2] => Array
    (
        [0] => idCidade
        [1] => idEstado
        [2] => idPais
    )

[3] => Array
    (
        [0] => >=
        [1] => =
        [2] => =
    )

[4] => Array
    (
        [0] => "bla"
        [1] => "2"
        [2] => "3"
    )

我已经还使其适用于 SQL 兼容的字符串和小数。但这对于正则表达式来说只是一个边缘工作。建议使用真正的解析器。 （虽然我不知道你的用例。）

Answer 2

试试这个。这会输出您需要的确切结果。

<?php  //Patherns
$regex  = '/([a-zA-Z_]+)\s*([>=<]*)\s*"([^"]*)"\s*(or|and)*/i';

//values to be extracted
$string = 'idCidade >= "bla" OR idEstado="2" and idPais="3"';

//regex function
preg_match_all(
    $regex,
    $string,
    $output
);

//displays the result
echo '<pre>';print_r($output);