php - DateTime::createFromFormat PHP < 5.3 的替代方案，缺少 strptime

Question

我前段时间问过这个问题。现在我需要在生产服务器上运行它，但是服务器是 5.2.9 ...

我如何编写一个替代函数，它会给我作为 DateTime::createFromFormat 函数的确切结果？

是的，我知道有重复，但它们都使用strptime. 但是当我尝试使用它时，我得到：Fatal error: Call to undefined function strptime().

不，我无法访问此生产服务器，因此我无法更改它的任何设置。

Answer 1

包括这个，你可以使用strptime：

/*
 * This work of Lionel SAURON (http://sauron.lionel.free.fr:80) is licensed under the
 * Creative Commons Attribution 2.0 France License.
 *
 * To view a copy of this license, visit http://creativecommons.org/licenses/by/2.0/fr/
 * or send a letter to Creative Commons, 171 Second Street, Suite 300, San Francisco, California, 94105, USA.
 */

/**
 * Parse a time/date generated with strftime().
 *
 * This function is the same as the original one defined by PHP (Linux/Unix only),
 *  but now you can use it on Windows too.
 *  Limitation : Only this format can be parsed %S, %M, %H, %d, %m, %Y
 * 
 * @author Lionel SAURON
 * @version 1.0
 * @public
 * 
 * @param $sDate(string)    The string to parse (e.g. returned from strftime()).
 * @param $sFormat(string)  The format used in date  (e.g. the same as used in strftime()).
 * @return (array)          Returns an array with the <code>$sDate</code> parsed, or <code>false</code> on error.
 */
if(function_exists("strptime") == false)
{
    function strptime($sDate, $sFormat)
    {
        $aResult = array
        (
            'tm_sec'   => 0,
            'tm_min'   => 0,
            'tm_hour'  => 0,
            'tm_mday'  => 1,
            'tm_mon'   => 0,
            'tm_year'  => 0,
            'tm_wday'  => 0,
            'tm_yday'  => 0,
            'unparsed' => $sDate,
        );

        while($sFormat != "")
        {
            // ===== Search a %x element, Check the static string before the %x =====
            $nIdxFound = strpos($sFormat, '%');
            if($nIdxFound === false)
            {

                // There is no more format. Check the last static string.
                $aResult['unparsed'] = ($sFormat == $sDate) ? "" : $sDate;
                break;
            }

            $sFormatBefore = substr($sFormat, 0, $nIdxFound);
            $sDateBefore   = substr($sDate,   0, $nIdxFound);

            if($sFormatBefore != $sDateBefore) break;

            // ===== Read the value of the %x found =====
            $sFormat = substr($sFormat, $nIdxFound);
            $sDate   = substr($sDate,   $nIdxFound);

            $aResult['unparsed'] = $sDate;

            $sFormatCurrent = substr($sFormat, 0, 2);
            $sFormatAfter   = substr($sFormat, 2);

            $nValue = -1;
            $sDateAfter = "";

            switch($sFormatCurrent)
            {
                case '%S': // Seconds after the minute (0-59)

                    sscanf($sDate, "%2d%[^\\n]", $nValue, $sDateAfter);

                    if(($nValue < 0) || ($nValue > 59)) return false;

                    $aResult['tm_sec']  = $nValue;
                    break;

                // ----------
                case '%M': // Minutes after the hour (0-59)
                    sscanf($sDate, "%2d%[^\\n]", $nValue, $sDateAfter);

                    if(($nValue < 0) || ($nValue > 59)) return false;

                    $aResult['tm_min']  = $nValue;
                    break;

                // ----------
                case '%H': // Hour since midnight (0-23)
                    sscanf($sDate, "%2d%[^\\n]", $nValue, $sDateAfter);

                    if(($nValue < 0) || ($nValue > 23)) return false;

                    $aResult['tm_hour']  = $nValue;
                    break;

                // ----------
                case '%d': // Day of the month (1-31)
                    sscanf($sDate, "%2d%[^\\n]", $nValue, $sDateAfter);

                    if(($nValue < 1) || ($nValue > 31)) return false;

                    $aResult['tm_mday']  = $nValue;
                    break;

                // ----------
                case '%m': // Months since January (0-11)
                    sscanf($sDate, "%2d%[^\\n]", $nValue, $sDateAfter);

                    if(($nValue < 1) || ($nValue > 12)) return false;

                    $aResult['tm_mon']  = ($nValue - 1);
                    break;

                // ----------
                case '%Y': // Years since 1900
                    sscanf($sDate, "%4d%[^\\n]", $nValue, $sDateAfter);

                    if($nValue < 1900) return false;

                    $aResult['tm_year']  = ($nValue - 1900);
                    break;

                // ----------
                default:
                    break 2; // Break Switch and while

            } // END of case format

            // ===== Next please =====
            $sFormat = $sFormatAfter;
            $sDate   = $sDateAfter;

            $aResult['unparsed'] = $sDate;

        } // END of while($sFormat != "")

        // ===== Create the other value of the result array =====
        $nParsedDateTimestamp = mktime($aResult['tm_hour'], $aResult['tm_min'], $aResult['tm_sec'],
                                $aResult['tm_mon'] + 1, $aResult['tm_mday'], $aResult['tm_year'] + 1900);

        // Before PHP 5.1 return -1 when error
        if(($nParsedDateTimestamp === false)
        ||($nParsedDateTimestamp === -1)) return false;

        $aResult['tm_wday'] = (int) strftime("%w", $nParsedDateTimestamp); // Days since Sunday (0-6)
        $aResult['tm_yday'] = (strftime("%j", $nParsedDateTimestamp) - 1); // Days since January 1 (0-365)

        return $aResult;
    } // END of function

} // END of if(function_exists("strptime") == false)

然而，由于 DateTime::createFromFormat 返回一个 DateTime 的对象，你不能在 PHP < 5.3 中得到完全相同的结果（除非你愿意编写你自己的类，它的行为与 DateTime 完全一样）