目标
我想将复杂的比较操作存储为PHP数组。然后，我想读取该数组来评估一组变量，并返回语句是真还是假。
问题
如何存储复杂的比较操作，以便稍后可以读取并评估此时存在的变量？这是实现这个功能的最佳方式吗？非常感谢您的帮助。
英文示例
如果($source = 200 OR $source = 300) AND ($age < 10 OR $age > 60)，则返回true，否则返回false。
注：变量可以是代码中的任何变量，我在这里使用source和age作为示例。嵌套数组可以比示例更深或更浅。
代码示例
$conditions = Array
(
[relation] => AND
[0] => Array
(
[relation] => OR
[0] => Array
(
[var] => source
[compare] => =
[value] => 300
)
[1] => Array
(
[var] => source
[compare] => =
[value] => 300
)
)
[1] => Array
(
[relation] => OR
[0] => Array
(
[var] => age
[compare] => <
[value] => 10
)
[1] => Array
(
[var] => age
[compare] => >
[value] => 60
)
)
解决方案
根据@sam-grondahl提供的答案，该函数能够处理您可以想到的任何嵌套逻辑。 接受正则表达式和数字比较。
$source = '300';
$age = '60';
$input_variables = array('source' => $source, 'age' => $age);
$conditions = array(
'relation' => 'and',
array(
'relation' => 'and',
array(
'var' => 'source',
'compare' => 'regex',
'value' => '(200|300)+'
),
array(
'relation' => 'OR',
array(
'var' => 'age',
'compare' => '=',
'value' => '59'
),
array(
'var' => 'age',
'compare' => '=',
'value' => '60'
)
)
),
array(
'relation' => 'or',
array(
'var' => 'age',
'compare' => '<',
'value' => '10'
),
array(
'var' => 'age',
'compare' => '>=',
'value' => '60'
)
),
array(
'var' => 'source',
'compare' => '=',
'value' => '300'
),
);
function evaluateConditions($condArray, $varablesArray){
if(!$condArray || !is_array($condArray)){throw new Exception('Missing Conditions Input Array');}
if(!$varablesArray || !is_array($varablesArray)){throw new Exception('Missing Variables Input Array');}
//PULL VARIABLES FROM ARRAY
foreach($varablesArray as $key_var => $value_var){
${$key_var} = $value_var;
}
///PROCESS THE ARRAY THAT CONTAINS THE COMPARISON ARRAY
if (!$condArray['relation']){
//FORMAT COMPARE INPUT
$condArray['compare'] = strtoupper(trim($condArray['compare']));
$condArray['compare'] = preg_replace('/^=$/','==',$condArray['compare']);
///ACCEPTED COMPARE VALUES
$accepted_compare_array = array('=','==','===','<>','!=','!==','>','>=','<','<=','REGEX');
//VERIFY REQUIRED FIELDS ARE PRESENT
if(!$condArray['var']){throw new Exception('Missing var');}
if(!$condArray['compare']){throw new Exception('Missing compare');}
if(!$condArray['value']){throw new Exception('Missing value');}
//VERIFY ALL VALUES
if($condArray['compare'] != 'REGEX' && !is_numeric($condArray['value'])){throw new Exception('Value is Not Numeric');}
if(!in_array($condArray['compare'], $accepted_compare_array)){throw new Exception('Invalid Compare Value');}
if(!preg_match("/^[a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*/",$condArray['var'])){throw new Exception('Invalid Var');}
if($condArray['compare'] == 'REGEX'){
$condArray['compare'] = preg_replace('/\//','\/',$condArray['compare']);
$eval_str = 'if(preg_match("/'.$condArray['value'].'/i", $'.$condArray['var'].')){return 1;} else{return 0;}';
}
else{
$eval_str = 'if($'.$condArray['var'].' '.$condArray['compare'].' '.$condArray['value'].'){return 1;} else{return 0;}';
}
return eval($eval_str);
}
else{
$condArray['relation'] = strtoupper(trim($condArray['relation']));
//VERIFY RELATION VALUE
$accepted_relation_array = array('AND','OR');
if(!in_array($condArray['relation'], $accepted_relation_array)){throw new Exception('Relation Invalid');}
//VERIFY THAT AT LEAST TWO ARRAYS
$array_count = 0;
foreach($condArray as $condArray_var){
if(is_array($condArray_var)){$array_count++;}
}
if($array_count < 2){throw new Exception('Missing Comparison Array');}
}
if (strtoupper($condArray['relation']) == 'OR') {
unset($condArray['relation']);
$eval_str = 'if(';
for($i=0; $i < count($condArray); $i++){
$eval_str .= evaluateConditions($condArray[$i], $varablesArray);
if($i != count($condArray)-1){$eval_str .= ' || ';}
}
$eval_str .= '){return 1;}else{return 0;}';
return eval($eval_str);
}
if (strtoupper($condArray['relation']) == 'AND'){
unset($condArray['relation']);
$eval_str = 'if(';
for($i=0; $i < count($condArray); $i++){
$eval_str .= evaluateConditions($condArray[$i], $varablesArray);
if($i != count($condArray)-1){$eval_str .= ' && ';}
}
$eval_str .= '){return 1;}else{return 0;}';
return eval($eval_str);
}
throw new Exception('General Error Occurred');
} //end of function
/////
try {
echo evaluateConditions($conditions, $input_variables);
}
catch (Exception $e) {
echo 'Caught exception: ', $e->getMessage(), "\n";
}