使用php从平面文件加载数据

如果您一直使用这种格式，您需要一个自定义的取消序列化机制。这里有一个适用于您的样本数据：

<?php
date_default_timezone_set("UTC");
class Record {
    public $nm = null;
    public $dt = null;
    public $ds = [];
    function isValid() {
        return $this->nm !== null && $this->dt !== null && count($this->ds) > 0;
    }
    function isEmpty() {
        return $this->nm == null && $this->dt == null && count($this->ds) == 0;
    }
}
function deserialise($filename, $newLineSeparator = "'n") {
    $incompleteRecords = 0;
    $records = [];
    $lines = explode($newLineSeparator, file_get_contents($filename));
    if ($lines)
        $lines[] = "*NEW RECORD";
    $record = new Record();
    foreach ($lines as $line) {
        $line = trim($line);
        if ($line == "*NEW RECORD") {
            if ($record->isValid())
                $records[] = $record;
            else if (!$record->isEmpty())
                $incompleteRecords++;
            $record = new Record();
        } else if (substr($line, 0, 5) == "NM = ") {
            $record->nm = substr($line, 5);
        } else if (substr($line, 0, 5) == "DT = ") {
            $record->dt = strtotime(substr($line, 5));
        } else if (substr($line, 0, 5) == "DS = ") {
            $record->ds[] = substr($line, 5);
        }
    }
    echo "Found $incompleteRecords incomplete records.'n";
    return $records;
}

我用你的数据试过了，得到了这个输出：

Found 0 incomplete records.
Array
(
    [0] => Record Object
        (
            [nm] => Stackoverflow
            [dt] => 1158278400
            [ds] => Array
                (
                    [0] => Overflow
                    [1] => Stack
                    [2] => stackoverflow.com
                    [3] => FAQ
                )
        )
    [1] => Record Object
        (
            [nm] => Google
            [dt] => 904867200
            [ds] => Array
                (
                    [0] => G+
                    [1] => Google
                    [2] => Search engine
                    [3] => Search
                )
        )
)

这是你想要的吗？

一些注意事项

• 一次加载内存中的所有内容；无配料
• 使用strtotime将日期解析为时间戳；您可能只想将它们加载为字符串（更容易），或者使用DateTime类。如果使用strtotime，请先设置空闲时区，如示例（date_default_timezone_set）所示
• 如果未设置NM、未设置DT或不存在DS条目，则假设记录无效。可以通过调整Record类上的isValid方法来修改此约束
• 没有对损坏的格式、小写字母等进行错误处理
• 假定'n为换行符。如果您有'r'n或'r，只需将它们作为第二个参数来调用deserialise函数

未经验证！！

$filename = "test.txt"; // Your Filename ;-)
$t = new FlatDbSearch($filename);
var_dump($t->select('DT', 'DS = "Google"'));
class FlatDbSearch {
    protected $lines;
    public function __construct($filename) {
        $this->lines = file($filename, FILE_IGNORE_NEW_LINES);
    }
    public function select($column, $where) {
        $parts = explode("=", $where);
        $searchKey = trim(str_replace('"', '', $parts[0]));
        $searchValue = trim(str_replace('"', '', $parts[1]));
        $column = trim(str_replace('"', '', $column));
        $lines = $this->searchForward($searchKey, $searchValue);
        if (count($lines) !== 0) {
            $results = $this->searchBackward($column, $lines);
            return $results;
        }
        return array();
    }
    protected function searchBackward($column, $lines) {
        $results = array();
        foreach($lines as $key) {
            for ($i = $key; $i > -1; $i--) {
                $parts = explode("=", $this->lines[$i]);
                if ($column == trim(str_replace('"', '', $parts[0]))) {
                    $results[] = trim(str_replace('"', '', $parts[1]));
                    break;
                }
            }
        }
        return $results;
    }
    protected function searchForward($searchKey, $searchValue) {
        $result = array();
        for ($i = 0; $i < count($this->lines); $i++) {
            $parts = explode("=", $this->lines[$i]);
            if (trim(str_replace('"', '', $parts[0])) == $searchKey) {
                if (trim(str_replace('"', '', $parts[1])) == $searchValue) {
                    $result[] = $i;
                }
            }
        }
        return $result;
    }
}