PHP get coordinates from KML file

问题

I'm using a KML file to extract coordinates and insert them in a multi-dimensional array. At first I'm trying to output only the coordinates on the page - and it doesn't seem to be working

Here is the code I've tried so far:

<?php
$url = "myKML.kml";
$contents = file_get_contents($url);
$xml      = new SimpleXMLElement($contents);

$value    = (string)$xml->Document->Placemark->Point->coordinates;
$coords   = array();
foreach($value as $coord) {    
$args     = explode(",", $value);
$coords[] = array($args[0], $args[1], $args[2]);
}

print_r($coord);
?>

Heres the KML structure:

<Document>
<name>...</name>
<open>1</open>
<Snippet maxLines='0'></Snippet>
<description>.../description>
<Style >
<BalloonStyle>
<text>
...
</text>
</BalloonStyle>
</Style>
<Placemark >
<name>...</name>
<styleUrl>...</styleUrl>
<Snippet maxLines='0'></Snippet>
<ExtendedData>
<Data name='__title'>
<value>...</value>
</Data>
<Data name='__imgUrl'>
<value>...</value>
</Data>
<Data name='__data'>
<value>...</value>
</Data>
</ExtendedData>
 <Point>
 <coordinates>14.8184806108,56.8630456924,196.0000000000</coordinates>
 </Point>
 </Placemark>

回答1:

The XML you're trying to parse isn't valid and you'll need to fix that before you can parse it. These are the problems I see:

You're not closing the <description> tag properly
The opening tag and closing tag doesn't match

After fixing the mistakes, your XML structure should look like below:

<Document>
<name>...</name>
<open>1</open>
<Snippet maxLines='0'></Snippet>
<description>...</description>
<Style >
    <BalloonStyle>
        <text>
            ...
        </text>
    </BalloonStyle>
</Style>
<Placemark >
    <name>...</name>
    <styleUrl>...</styleUrl>
    <Snippet maxLines='0'></Snippet>
    <ExtendedData>
        <Data name='__title'>
            <value>...</value>
        </Data>
        <Data name='__imgUrl'>
            <value>...</value>
        </Data>
        <Data name='__data'>
            <value>...</value>
        </Data>
    </ExtendedData>
    <Point>
        <coordinates>14.8184806108,56.8630456924,196.0000000000</coordinates>
    </Point>
</Placemark>
</Document>

Coming to your code, you have the following:

$value    = (string)$xml->Document->Placemark->Point->coordinates;

You're casting $value as a string, so the foreach loop wouldn't work. foreach requires an array as it's argument, but you'll be passing a string instead.

The corrected code should look like:

$value = (array) $xml->Placemark->Point->coordinates;

$coords   = array();
foreach($value as $coord) {    
    $args     = explode(",", $coord);
    $coords[] = array($args[0], $args[1], $args[2]);
}

Output:

Array
(
    [0] => Array
        (
            [0] => 14.8184806108
            [1] => 56.8630456924
            [2] => 196.0000000000
        )

)

Demo!

The above code will try and get all the coordinates into the $coords array. If you want to get only one coordinate, you can cast it as a string, then do the following:

$value = (string) $xml->Placemark->Point->coordinates;
list($coord1, $coord2, $coord3) = explode(',', $value);
$coords = array($coord1, $coord2, $coord3);
print_r($coords);

This will generate the following array:

Array
(
    [0] => 14.8184806108
    [1] => 56.8630456924
    [2] => 196.0000000000
)

Demo!

UPDATE

The structure of the KML file you posted is a bit different. The below code should work:

foreach ($xml->Document->Placemark as $coord) {
    $coord = (string) $coord->Point->coordinates."<br/>";
    $args     = explode(",", $coord);
    $coords[] = array($args[0], $args[1], $args[2]);
}
print_r($coords);

回答2:

$kml = new SimpleXMLElement(file_get_contents('myKML.kml'));

foreach ($kml->xpath('//Placemark/Point/coordinates') as $kml_coordinates) {
    // for legibility...
    sscanf((string) $kml_coordinates, '%f,%f,%f', $latitude, $longitude, $altitude);
    $coords[] = array($latitude, $longitude, $altitude);
    // for simplicity...
    $coords[] = explode(',', (string) $kml_coordinates);
}

Demo: https://eval.in/65272

来源：https://stackoverflow.com/questions/19887194/php-get-coordinates-from-kml-file

标签

php

xml

arrays

coordinates

kml