Question

我的PHP代码中有一个正则表达式，应该匹配每个数字和所有“运算符”+ - * / ^ r（）我的正则表达式看起来像这样

/(?:(\d+(?:\.\d+)|(\+)|(-)|(\*)|(\/)|(\^)|(r)|($)|($)))/

当使用字符串preg_match_all($expression,"2+2",$results)进行测试时，它会让我回来

Array
(
    [0] => Array
        (
            [0] => '+'
        )

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

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

    [3] => Array
        (
           [0] => ''
        )

    [4] => Array
        (
            [0] => ''
    )

    [5] => Array
        (
            [0] => ''
        )

    [6] => Array
        (
            [0] => ''
        )

    [7] => Array
        (
            [0] => ''
        )

    [8] => Array
        (    
            [0] => ''
        )

    [9] => Array
        (
            [0] => ''
        )

)

当（如果它正常）我应该得到这个

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

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

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

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

    [4] => Array
        (
           [0] => ''
           [1] => ''
           [2] => ''
        )
    ...

)

注意，它会为所有运营商返回类似的行为，它似乎完全忽略这些数字

注意，我需要单独的捕获组，因此每个结果都有不同的匹配索引

Answer 1

你可以这样做：

$pattern = '~\d+(?:\.\d+)?|[-+*/^r()]~';

PHP正则表达式意外匹配

1 个答案: