从 MySQL 几何 WKT 数据获取 geojson 线串

Getting geojson linestring from MySQL geometry WKT data

我正在尝试使用很棒的 PHP-Database-GeoJSON 库从这里 https://github.com/bmcbride/PHP-Database-GeoJSON 获取 GeoJSON linestring 格式,但目前没有任何运气

我使用该库成功地从 MySQL table 调用了简单的点,但是对于线和多边形,情况有点不同。

首先,我用几何字段创建了 table,如下所示:

-- phpMyAdmin SQL Dump
-- version 4.4.6
-- http://www.phpmyadmin.net
--
-- Host: localhost
-- Generation Time: Jan 20, 2016 at 10:12 PM
-- Server version: 5.6.24
-- PHP Version: 5.6.8

SET SQL_MODE = "NO_AUTO_VALUE_ON_ZERO";
SET time_zone = "+00:00";


/*!40101 SET @OLD_CHARACTER_SET_CLIENT=@@CHARACTER_SET_CLIENT */;
/*!40101 SET @OLD_CHARACTER_SET_RESULTS=@@CHARACTER_SET_RESULTS */;
/*!40101 SET @OLD_COLLATION_CONNECTION=@@COLLATION_CONNECTION */;
/*!40101 SET NAMES utf8 */;

--
-- Database: `web_gis`
--

-- --------------------------------------------------------

--
-- Table structure for table `wkt_linija`
--

DROP TABLE IF EXISTS `wkt_linija`;
CREATE TABLE IF NOT EXISTS `wkt_linija` (
  `id` int(11) NOT NULL,
  `oznaka` varchar(50) NOT NULL,
  `opis` varchar(200) NOT NULL,
  `sirina` varchar(200) NOT NULL,
  `podloga` varchar(200) NOT NULL,
  `mo` varchar(200) NOT NULL,
  `geometry` geometry NOT NULL
) ENGINE=InnoDB AUTO_INCREMENT=2 DEFAULT CHARSET=utf8;

--
-- Dumping data for table `wkt_linija`
--

INSERT INTO `wkt_linija` (`id`, `oznaka`, `opis`, `Å¡irina`, `podloga`, `mo`, `geometry`) VALUES
(1, 'K-8', 'D206 - Vulica - Kraljevec - Horvati - Kordej - S1', '5 m', 'Asfalt-makadam', 'Kostel', '[=11=][=11=][=11=][=11=][=11=][=11=][=11=]¿[=11=][=11=][=11=]§5l¹r/@##LêG@eëŸëÑr/@,†‰©G@E¤úâèr/@*éöŠG@Ç4sùr/@õYd\rG@}VHÉs/@·-G@-©`›\Zs/@ÜdÏG@Bß%s/@}*†G@®ñ„/s/@óÅ,ÞG@Ùª³ã7s/@w!™cÿG@PÝAs/@zOöüG@‘t·ÀMs/@Ê.›ÖúG@W…_e]s/@w;yùG@e­‰tts/@š¢ýöG@Ñ„»”s/@S`ùåôG@±å¡´s/@»÷‡óG@ÉSÔÏs/@Ê5@DòG@Ê„Sñs/@<zòG@¥HÖHt/@Ï\n±ÏñG@8Wt/@«ôÚðG@Þôz(t/@äò=îG@׎¬/9t/@‚áoéG@•‡[=11=]Kt/@ûq[=11=]äG@kª†Xt/@n”TTßG@%-šmjt/@ÒÃ|‡ÛG@a =‰t/@\Zñ‡ÕG@‚~bÉt/@bnåÈG@’Oƒøt/@Ñ»oÙ¿G@r¶¡ãu/@F+BºG@ðèð9u/@õO‘¶G@õmeVu/@íójB´G@¬íæ_gu/@’''™²G@žº’îou/@›CØ°G@è1Bou/@Ž­G@8è’ju/@ýEŒªG@|¯Yu/@#H|L¦G@V8ÏHu/@ò†M¢G@¹¡_„0u/@ÑÞ„žG@ø*È>/u/@ä]*RžG@s«®[=11=]\ru/@› ššG@Ãbát/@m«NÈ—G@[÷¾t/@)hNè“G@…!E‹t/@‘FÕŽG@[$ïtbt/@ŠuŠG@8#dJt/@c€ÌD‡G@윔Î.t/@žZ.†G@4/bt/@qx›\Z†G@¶´·¯òs/@iŒ¶&†G@×Í>¼Õs/@Ãís³†G@ÃW‡@µs/@RqÈG@B-Ä…¡s/@B^µŠG@Ò3©‘s/@9Tþ5‰G@å»Øáˆs/@†ÍÀ†G@£ã…s/@S»ÌƒG@j)jm†s/@(E瘀G@üÊqцs/@[=11=]{[=11=]zG@ÂÄas/@Ë/c¸wG@¬¹…÷‘s/@d1oLsG@’€Ms/@c¹pG@©Æ+̤s/@àv¬lG@} ±s/@°{§,hG@»Bi,¿s/@ÆÇúœcG@sbæ1Ïs/@JJ‹#`G@ø;·rÑs/@''>v¦_G@§`]Ös/@òc±]G@\Z¯žØs/@ZÂ`Ë\G@/à/?Ýs/@µeòWG@ïú®ùës/@³¾â¿RG@®žéñs/@M.ö±NG@pÿ^òs/@ ÍaNG@<Éhýs/@rÙ–LG@¸*Bt t/@<ŸˆIG@Þù)t/@ËGò>DG@ûÄj(t/@A©ÂK@G@¡›ãÕ-t/@:íB=G@o,5t/@Ÿ²@;G@a¬t*Bt/@ ¤‘8G@!zKt/@L¬ž6G@lj}Ut/@Ы¼¹4G@}Ö¼\wt/@›É¤û.G@JI&4œt/@ÖD¨(G@2Jæš±t/@‘&¡#G@âq^³±t/@8Ûe›#G@“º»MÇt/@ï  G@‘£ßt/@™(FÏG@ª8W÷t/@¿¼¹UG@íQñGu/@º3æGG@²Þ2Ýu/@_¶L¶G@âR€u/@j|æ’G@''‚Öau/@½-ÞùG@ö¹­)u/@óèP‡G@-x1Ju/@È3¤G@˜Ôî%u/@Û$ÍG@H‘ðu/@<˜G@UþBu/@=JPýG@¾ß"u/@K›tãúG@Oºw¤#u/@†‘ËÁúG@HO]N,u/@“;­GùG@eæß?u/@B_LöG@ÌvmÝVu/@áó×óG@˜§Ev[u/@¥2ÄðG@@TÏl_u/@â+qgíG@ɽ\Zeu/@[]a…çG@:ø )gu/@g-áG@é’du[u/@>6wMÞG@úmNƒUu/@­V¦óÙG@ˆøÆQu/@ÔKÿÕG@¥K?MQu/@–ÑKÒG@œu~Vu/@¹Ã[õÎG@­È­ø]u/@ ÛñoÌG@D¦Åhu/@ÙŠ˜,ÊG@¤DÕ£wu/@Yá¿ÈG@+\Z‰u/@a¦­ÇG@lV3\r¤u/@׬œ?ÆG@ €ì¸u/@R½JJÅG@3}qaÂu/@èjûÄG@¢U§½Èu/@Í-)ÂG@j(Íu/@è.P¿G@`ûfåÑu/@ÂÁ¸F»G@þ¨²Öu/@œ™? ¸G@–Çû’Þu/@‰Œû]¶G@ÏÀéu/@3%´G@LhÝ]üu/@ß6$±G@]‘ó  v/@ ©Zð®G@0s+v/@¥Éæ¬G@¤]¶v/@ŽòרG@˜.ôæ\Zv/@®÷—Š¤G@h v/@"á[=11=]M—G@Ðitv/@ׄ½’G@ðüv/@Ý5­BŽG@µ3 \nv/@é¨þ‹G@ZTLv/@øP{‰ˆG@r;$P÷u/@ÏV’>„G@ëàrYëu/@˜wÒ9G@à°y!Ýu/@ðÿMy~G@ÐfÃu/@g"òázG@3H¹Œ­u/@kU¸HwG@䉽;šu/@‰ôó™rG@ÿQJu/@ÜâroG@¶‰Š)‰u/@F>#klG@PC´ú€u/@û]ŸªhG@ˆÚzu/@0EóLfG@Á¼©pu/@òÔ¦UdG@€]"X[u/@[=11=]³''0bG@gÖæˆMu/@Ç>\`G@Ð\n|–Fu/@!¤……^G@''Ú9ôDu/@×Oi\G@íµ PFu/@DmÅ^YG@¨®ÍHu/@¡žîUG@_¶WéJu/@Ål RG@£y¯OMu/@e¡ÆMG@™3¯äKu/@FpmHG@,šlAHu/@bä;‰DG@^J+îCu/@¾äPBG@æˆO\=u/@y^ßþ?G@Î2¿.u/@‘šþ=G@œ—7Ru/@Óœ79G@˜¡q‹u/@+ê©ñ4G@ÖŒ„u/@³ì%–1G@÷fáÔ  u/@%ó\Z|.G@|´zºu/@&í“´+G@"¬+u/@OÉó\)G@Þ_µ™u/@lW™%G@#§G[)u/@õŽ(''G@$t/“4u/@EIroG@q/;^>u/@l”ÂG@¤¿²¯Lu/@³ê‰G@ß|Smau/@^GnG@Ê  »Çuu/@ÃÖ¤ÃG@”1î‡u/@èÐ…\ZG@7úHd•u/@/U€G@>bo¿¡u/@¢ôeöG@uß®u/@&\nP-[=11=]G@ï‹}r·u/@Tñ-ºüG@sU~ø¹u/@œ^Ì6úG@²eóºu/@걓\n÷G@~‹W)¸u/@bÍôG@Y0ø±u/@Üa*ÔòG@ug#k¨u/@müñG@INñ®šu/@i(q‹ñG@7ŸVˆu/@Š"ÈðG@Vÿ•ru/@MðFwïG@Éúeäbu/@i¶ÖíG@Fà;Uu/@ZÛ:ÐëG@ˆ+ìOu/@‘D4éG@t.Mu/@z 6æG@ä€3sHu/@èY;ãG@ÒŸng>u/@x9„9àG@"‚ƒX1u/@3òïÝG@JT2u/@ïv\n–ÛG@7¯u/@%F[=11=]ØG@—ÍH0ôt/@‰œìÄÔG@');

--
-- Indexes for dumped tables
--

--
-- Indexes for table `wkt_linija`
--
ALTER TABLE `wkt_linija`
  ADD PRIMARY KEY (`id`);

--
-- AUTO_INCREMENT for dumped tables
--

--
-- AUTO_INCREMENT for table `wkt_linija`
--
ALTER TABLE `wkt_linija`
  MODIFY `id` int(11) NOT NULL AUTO_INCREMENT,AUTO_INCREMENT=2;
/*!40101 SET CHARACTER_SET_CLIENT=@OLD_CHARACTER_SET_CLIENT */;
/*!40101 SET CHARACTER_SET_RESULTS=@OLD_CHARACTER_SET_RESULTS */;
/*!40101 SET COLLATION_CONNECTION=@OLD_COLLATION_CONNECTION */;

这是图片。我不知道为什么,但是当我导出 table 时,我在几何行中得到了奇怪的符号,例如“/@‰œìÄÔG@”。是因为我在创建几何字段时选择了 GeomFromText 函数吗?

真正的问题是这个。当我使用这段代码从 MySQL 中提取数据并转换为 GeoJSON 时:

<?php

include_once('geoPHP/geoPHP.inc');

$conn = new PDO('mysql:host=localhost;dbname=web_gis;charset=utf8','neven','gis',array(PDO::MYSQL_ATTR_INIT_COMMAND => 'SET NAMES utf8'));

$sql = 'SELECT *, geometry AS wkt FROM wkt_linija';

$rs = $conn->query($sql);
if (!$rs) {
    echo 'An SQL error occured.\n';
    exit;
}

$geojson = array(
   'type'      => 'FeatureCollection',
   'features'  => array()
);

while ($row = $rs->fetch(PDO::FETCH_ASSOC)) {
    $properties = $row;

    unset($properties['wkt']);
    unset($properties['geometry']);
    $feature = array(
         'type' => 'LineString',
         'geometry' => json_decode(($row['wkt'])),
         'properties' => $properties
    );

    array_push($geojson['features'], $feature);
}
header('Content-type: application/json');
echo json_encode($geojson, JSON_NUMERIC_CHECK);
$conn = NULL;
?>

几何字段被忽略,我得到没有任何几何的结果,如下所示:

{"type":"FeatureCollection","features":[{"type":"LineString","geometry":null,"properties":{"id":1,"oznaka":"K-8","opis":"D206 - Vulica - Kraljevec - Horvati - Kordej - S1","sirina":"5 m","podloga":"Asfalt-makadam","mo":"Kostel"}}]}

如果我没记错的话应该会得到这样的东西:

{"type": "FeatureCollection","features": [
{ "type": "Feature", "properties": { "OBJECTID": 857, "OZNAKA": "K-8", "OPIS": "D206 - Vulica - Kraljevec - Horvati - Kordej - S1", "�IRINA": "5", "PODLOGE": "Asfalt-makadam", "DULJINA": 2.714530, "SHAPE_Leng": 2714.529879, "JLS": "Pregrada", "MO": "Kostel" }, "geometry": { "type": "LineString", "coordinates": [ [ 15.724070907944066, 46.188443457771676 ], [ 15.724257815619874, 46.188344185018963 ], [ 15.724433034034641, 46.188218470155633 ], [ 15.72455940264949, 46.188111948013024 ], [ 15.724699297027877, 46.187990209886379 ], [ 15.724812369870586, 46.187860416649634 ], [ 15.72489216542548, 46.187729597634622 ], [ 15.72497191850638, 46.187587520467694 ], [ 15.725035777742436, 46.18748135544859 ], [ 15.725105549827283, 46.187407292181923 ], [ 15.725202581781817, 46.187342477581822 ], [ 15.725321929846059, 46.187288459964229 ], [ 15.725497857862772, 46.187225059863707 ], [ 15.725739143267136, 46.18716120411468 ], [ 15.725983191502424, 46.187106791868665 ], [ 15.726194987431329, 46.187080890038104 ], [ 15.726450533317252, 46.187073593715894 ], [ 15.726602817685782, 46.187066995092771 ], [ 15.726732946011916, 46.187037820050442 ], [ 15.726868107327785, 46.186958068465223 ], [ 15.726998796285825, 46.18681143294458 ], [ 15.72713472037392, 46.186645560888834 ], [ 15.727237900023473, 46.186502972887737 ], [ 15.727374482221942, 46.186387000961659 ], [ 15.727609563629075, 46.186189834001382 ], [ 15.72809649660417, 46.185818387861914 ], [ 15.728458503155057, 46.185542277867746 ], [ 15.728743661394422, 46.185371657495338 ], [ 15.728957680163198, 46.185259021798828 ], [ 15.729172360784085, 46.185188581679405 ], [ 15.72930431074095, 46.185137873121803 ], [ 15.729369597827198, 46.185060721013734 ], [ 15.729363091545522, 46.184984028820601 ], [ 15.729328718981932, 46.184892184228353 ], [ 15.729199870961573, 46.184762535747971 ], [ 15.729071126927163, 46.184640592675251 ], [ 15.728885780977054, 46.184525116727102 ], [ 15.728876077589561, 46.184519072234053 ], [ 15.728614827463138, 46.184405640049697 ], [ 15.728282035417173, 46.184319532788187 ], [ 15.728019456787038, 46.184201277050597 ], [ 15.727625044660053, 46.184046453459025 ], [ 15.727313665573254, 46.183902676002639 ], [ 15.72713005952758, 46.183815574507001 ], [ 15.726919608727677, 46.183782381293177 ], [ 15.726687496419437, 46.183780027306859 ], [ 15.726460925269162, 46.183781470427512 ], [ 15.72624004618312, 46.183798247915114 ], [ 15.725992218514767, 46.183861189085874 ], [ 15.725841694066393, 46.183920515406967 ], [ 15.725715865521043, 46.183874844726638 ], [ 15.725653703409941, 46.18379975520206 ], [ 15.725630852584601, 46.18370970853416 ], [ 15.725634974679185, 46.183611977505564 ], [ 15.725637955799805, 46.183427810892681 ], [ 15.725685548243181, 46.183341072493555 ], [ 15.725723013948333, 46.183206133168625 ], [ 15.725809501193257, 46.183107700844715 ], [ 15.725866680473091, 46.183003917087035 ], [ 15.725960645833988, 46.182866651324161 ], [ 15.726067912911608, 46.182727453662253 ], [ 15.726190146802059, 46.182621424687184 ], [ 15.726207337253058, 46.182606513725027 ], [ 15.726244838952267, 46.182546780957537 ], [ 15.726262053423898, 46.182519361730286 ], [ 15.726297354311184, 46.182371391634128 ], [ 15.726409723863496, 46.182212815966885 ], [ 15.726455021424353, 46.182089085774898 ], [ 15.726458519588704, 46.1820795299138 ], [ 15.726542714259828, 46.182008813530857 ], [ 15.726634629323016, 46.181917731008497 ], [ 15.726792632784449, 46.181770199109074 ], [ 15.726870857759003, 46.181649656342877 ], [ 15.726912197145625, 46.181557050493623 ], [ 15.72696727853892, 46.181495749681858 ], [ 15.727067305319169, 46.181413846381595 ], [ 15.727138343041192, 46.181354299035405 ], [ 15.727214739777891, 46.181296555637914 ], [ 15.727473161746497, 46.181121306860597 ], [ 15.727754239724749, 46.180928261966685 ], [ 15.727917519198943, 46.180774825857164 ], [ 15.727918248442567, 46.180774140104802 ], [ 15.728083066145052, 46.180681243365932 ], [ 15.728268727778216, 46.180597218758699 ], [ 15.728449559847867, 46.180521693889652 ], [ 15.728548286636363, 46.180459010508869 ], [ 15.728575622997003, 46.180441653687687 ], [ 15.728626260838556, 46.180345881025303 ], [ 15.728632981715306, 46.180266602979351 ], [ 15.728631308037603, 46.180130877024475 ], [ 15.728609388865232, 46.180042767469388 ], [ 15.72863119640742, 46.179925578113505 ], [ 15.728675382393831, 46.179736203157688 ], [ 15.728754103415818, 46.179605518578782 ], [ 15.728781671000469, 46.179531509339164 ], [ 15.728787555327612, 46.17952749671808 ], [ 15.728853653803199, 46.179482421480451 ], [ 15.729002926254177, 46.179391428482766 ], [ 15.729178351986228, 46.179316475034064 ], [ 15.729213424685256, 46.17922260735417 ], [ 15.729243660267571, 46.179119997271997 ], [ 15.729286990802217, 46.178940460721343 ], [ 15.729302693271269, 46.178746820197198 ], [ 15.729213398482402, 46.178659136971405 ], [ 15.729168036769796, 46.178526359767922 ], [ 15.729134552992278, 46.178405644044375 ], [ 15.72913590810442, 46.178292729463621 ], [ 15.729175521649999, 46.178190870100885 ], [ 15.729232569898466, 46.178113930791596 ], [ 15.729312949540265, 46.178044867023068 ], [ 15.729428405555446, 46.177993744555984 ], [ 15.729561627668394, 46.177968698730346 ], [ 15.729767239109798, 46.177925063611546 ], [ 15.729926481857566, 46.177895819181359 ], [ 15.729998631576199, 46.177859065783025 ], [ 15.730047156025481, 46.177800306667997 ], [ 15.730080843602126, 46.177713416007506 ], [ 15.730117005177533, 46.177590217793764 ], [ 15.730153622997474, 46.177509337477403 ], [ 15.730213731036013, 46.177440402819293 ], [ 15.730294124893048, 46.177372576295973 ], [ 15.730441029813072, 46.177280928037128 ], [ 15.730544656814056, 46.177213711041304 ], [ 15.730607373995639, 46.177126634301466 ], [ 15.730649660998102, 46.177027590548377 ], [ 15.730673997218489, 46.176896404459839 ], [ 15.730686159036875, 46.176492333821685 ], [ 15.730678213040187, 46.176331131495026 ], [ 15.730644702457511, 46.17621644456424 ], [ 15.730591136985689, 46.176118015618904 ], [ 15.730532059952845, 46.176041779721288 ], [ 15.730402473852994, 46.175910779432904 ], [ 15.730311198495164, 46.175818660514039 ], [ 15.730202718834732, 46.175734675489252 ], [ 15.730003845739928, 46.175625079374008 ], [ 15.729839704148707, 46.175515260702774 ], [ 15.729692332160035, 46.175372356528051 ], [ 15.729618528196623, 46.175276053085071 ], [ 15.729562090073937, 46.175183670242902 ], [ 15.729499659065965, 46.175069167915318 ], [ 15.72944644429414, 46.1749969661563 ], [ 15.729370166749847, 46.174936968289231 ], [ 15.729212526507354, 46.174871463188538 ], [ 15.729107168367774, 46.174815683654337 ], [ 15.729054167405963, 46.17475956941076 ], [ 15.729041702329665, 46.17469517134213 ], [ 15.72905208551216, 46.174602362060369 ], [ 15.729071071151182, 46.174497439541717 ], [ 15.729087154347495, 46.174396528594606 ], [ 15.72910546319037, 46.174248531959883 ], [ 15.729094644915493, 46.17408531172007 ], [ 15.729066891200169, 46.17396655487461 ], [ 15.729033892425999, 46.173890151499549 ], [ 15.728983769139131, 46.173827990595733 ], [ 15.728872275277265, 46.173739313429117 ], [ 15.728754586492691, 46.173621131114167 ], [ 15.72865710985279, 46.173490722623988 ], [ 15.72860349855311, 46.173388260381579 ], [ 15.728590633883398, 46.173293603095125 ], [ 15.728612735251083, 46.173208782415074 ], [ 15.728646626318611, 46.173137301479635 ], [ 15.728726199522438, 46.173007798074508 ], [ 15.728831150528611, 46.172825712970656 ], [ 15.728916739981351, 46.172712260059178 ], [ 15.72899145576932, 46.172630617446742 ], [ 15.729100695199868, 46.172549311964211 ], [ 15.729258934441928, 46.172437431420562 ], [ 15.729414216596428, 46.172325568664313 ], [ 15.729546276642203, 46.172213855113853 ], [ 15.729655393513083, 46.172107398664927 ], [ 15.729749662729883, 46.171995925696379 ], [ 15.729846939429743, 46.171880401689393 ], [ 15.729915216279521, 46.171775124009088 ], [ 15.729934468671422, 46.171698426999882 ], [ 15.729941946170445, 46.171601602665604 ], [ 15.729920665680535, 46.17153322935043 ], [ 15.729873420226953, 46.171473046011414 ], [ 15.729800556251329, 46.171447282199416 ], [ 15.7296957654536, 46.171433859112604 ], [ 15.729553262542693, 46.171410576691585 ], [ 15.729389846247617, 46.171370420110726 ], [ 15.729270112465558, 46.171320761745136 ], [ 15.729164786156741, 46.171258953798954 ], [ 15.729123053626395, 46.17117657711163 ], [ 15.729104461899636, 46.171087984683425 ], [ 15.729068374669119, 46.170993474941326 ], [ 15.728991729978507, 46.170905294001329 ], [ 15.728892103245986, 46.170835384142627 ], [ 15.728746006764606, 46.170763735875759 ], [ 15.728573253271504, 46.170655965932646 ], [ 15.728425511252494, 46.170555701764052 ] ] } }
]
}

我不知道我错过了什么。是 .php 代码块中的东西,还是我创建 table 失败并在创建几何字段时选择了错误的函数,真的不知道。

感谢您对问题的任何帮助或建设性批评。

更新

即使将此代码块包含在上述 .php 文件中(从此处复制 https://github.com/phayes/geoPHP

<?php
include_once('geoPHP/geoPHP.inc');

function wkt_to_json($wkt) {
  $geom = geoPHP::load($wkt,'wkt');
  return $geom->out('json');
}
...

我收到通知

Notice: Undefined offset: 1 in C:\xampp\htdocs\PHP-GEOJSON\MySQL_LINIJA\geoPHP\lib\adapters\WKT.class.php on line 23

致命错误

Fatal error: Call to a member function out() on null in C:\xampp\htdocs\PHP-GEOJSON\MySQL_LINIJA\line.php on line 16

在一些帮助下(公平地说,他们真的很有帮助)我终于弄明白了。

所以,这是交易。在几何字段 (MySQL) 中,我使用了 GeomFromText 函数,对于 VALUE 使用的格式如下:

'LINESTRING(15.710658104182732 46.20239760250581,15.710776991330624 46.202150210442475,15.710822931962284 46.20192080948476,15.710831682524589 46.20165203949391,15.710829367910724 46.201478170096806,15.710778748807499 46.201345541255364,15.710749581923572 46.20098083884202,15.710768970490234 46.200904345256404,15.710812698319572 46.200819215538004,15.710877059895306 46.2007537567,15.710904378497835 46.20066024293927,15.710912159473589 46.20039950452849,15.710894434522887 46.20028929894646,15.710844620624444 46.20021889590132,15.710754497671333 46.20018268546197,15.710619472746819 46.200141098973376,15.710468078447006 46.20009395676996,15.710300020035252 46.20001863058078,15.71013294549417 46.200019670809,15.710063999207861 46.20004555880265,15.709954779718144 46.20010846583362,15.709825367334812 46.200185643990416,15.709740155452225 46.20021445995833,15.7095978600008 46.20024080222257,15.709435298637604 46.20027575661596,15.709362166147757 46.20029318215561,15.709321746574172 46.200318892298654,15.70924501465025 46.2003731121604,15.709176908852976 46.20046404855626,15.70912593824907 46.2006199379506,15.709082098558873 46.200696581456555,15.709041746284855 46.20072794679033,15.708980768498824 46.20073963902233,15.708833996835912 46.20073489545015,15.70867866945619 46.200699088541356,15.708441515485225 46.200638334448556,15.70831071551633 46.200608030417,15.708025541089574 46.20061546014786,15.707936251453559 46.200644298279066,15.707786277558592 46.20070745795111,15.707623895583048 46.200756550625464,15.707461001390076 46.20076604727856,15.707318051223131 46.20074147497647,15.707207479007135 46.20069973463324,15.707066607106702 46.20060074856272,15.70664318279083 46.20030616960038,15.705882062458974 46.19972242368199,15.70511493399327 46.19906980655475,15.704648034594763 46.1987219944351,15.70450919728616 46.19858019598824,15.704291928591257 46.19833188738757,15.704161428771785 46.198172204352296,15.703537141003846 46.19756976517491,15.703216667780048 46.197286427418,15.702992669467902 46.197180815640245,15.702837928060974 46.19713421658259,15.702717672096156 46.19710523755276,15.70259748698871 46.19708220158732,15.701539642071204 46.19672612421737,15.701342168546992 46.19668573136494,15.701050429965196 46.19663997213334,15.700655562790246 46.196565125734026,15.700286457978665 46.19649606343836,15.700088834888449 46.196443782082085,15.699934103148394 46.196397179030086,15.699769973735597 46.1962852481137,15.699587967151555 46.19611398852277,15.699336247021442 46.19584804901749,15.699059302528688 46.19561793070997,15.698759082297304 46.195383057970396,15.698344688297988 46.195118114465565,15.698137525323025 46.19498861375236,15.698007207286828 46.1948408097566,15.697833392097015 46.19463977545958,15.697738075051644 46.19455119870973,15.697513417413118 46.19439208391872,15.696752249589233 46.19379044428983,15.696406296846584 46.19351913197643,15.69616377139154 46.19330068008819,15.695964208560289 46.19309385821015,15.695790263799942 46.19288093427891,15.695446508778891 46.192414313313975)',4326

MySQL table 中的数据似乎存储在 WKB 中,但不知何故,当我查看它时,它会自动转换为 WKT!?

我真的不确定为什么会这样或者它是如何发生的,但是为了从 MySQL table 中提取数据并转换为 GeoJSON,我使用了 geoPHP 库和这些行代码:

// library downloaded from here https://github.com/phayes/geoPHP
include_once('../geoPHP/geoPHP.inc');

// function for calling wkb_to_json processor
function wkb_to_json($wkb) {
    $geom = geoPHP::load($wkb,'wkb');
    return $geom->out('json');
}

// checking if databasestring is UTF8 
$conn = new PDO('mysql:host=localhost;dbname=web_gis;charset=utf8','neven','gis',array(PDO::MYSQL_ATTR_INIT_COMMAND => 'SET NAMES utf8'));

// using  AsBinary on geometry field
// Converts a value in internal geometry format to its WKB representation and returns the binary result
$sql = 'SELECT *, AsBinary(geometry) AS wkb FROM wkt_line';

$rs = $conn->query($sql);
if (!$rs) {
    echo 'An SQL error occured.\n';
    exit;
}

$geojson = array(
   'type'      => 'FeatureCollection',
   'features'  => array()
);

while ($row = $rs->fetch(PDO::FETCH_ASSOC)) {
    $properties = $row;

    unset($properties['wkb']);
    unset($properties['geometry']);
    $feature = array(
         'type' => 'Feature',//outer feature
         'geometry' => json_decode(wkb_to_json($row['wkb'])),
         'properties' => $properties
    );

    array_push($geojson['features'], $feature);
}

header('Content-type: application/json');
echo json_encode($geojson, JSON_NUMERIC_CHECK);
$conn = NULL;

而且成功了!享受...

我的简单解决方法是使用 MySQL 将 POINT 和 LINESTRING 几何图形转换为 GeoJSON。在我的例子中,单个 table 存储点和线串几何图形,但这可以很容易地扩展为单部分多边形和多点:

SELECT
  IF(LENGTH(AsText(network_objects.geometry)) = 0,
   'null',
  IF(LOCATE('POINT',AsText(network_objects.geometry)),
  CONCAT('{"type": "Point", "coordinates":',
    REPLACE(
        REPLACE(
            REPLACE(
                AsText(network_objects.geometry), ' ', ','
            ),
            'POINT(', '['
        ), ')', ']'
    ),'}'
  ),

  IF(LOCATE('LINESTRING', AsText(network_objects.geometry)),
    CONCAT('{"type": "LineString", "coordinates":',
    REPLACE(
        REPLACE(
            REPLACE(
                REPLACE(
                    AsText(network_objects.geometry), ',' ,'],['
                ),
                ' ',','
            ),
            'LINESTRING(', '[['
        ),')',']]'
    ),'}'),
    'null'
  )
    )
) as geometry_type_string
FROM geometry_table;

这将输出 "geometry" 的值:-属性 的 GeoJSON 对象,如

{"type": "LineString", "coordinates":[[15.42324565,60.38242968],[15.42307974,60.38252172]]}