PHP多次foreach相同的值，但只打印一次

Question

I have a xml file with Shows and Seasons in it.

What i'm trying to do is to read out the seasons for one show. But the problem is that each seasons is represented multiple times under the same show.

I only want each season number printed out one time like:

Season 1
Season 2

But what i got now is:

Season 1
Season 2
Season 2
Season 1
Season 1

My xml looks like

<?xml version="1.0"?>
<episodeview>
<episodeview>
    <idShow>1</idShow>
    <idSeason>1</idSeason>
</episodeview>
<episodeview>
    <idShow>1</idShow>
    <idSeason>2</idSeason>
</episodeview>
<episodeview>
    <idShow>1</idShow>
    <idSeason>2</idSeason>
</episodeview>
<episodeview>
    <idShow>1</idShow>
    <idSeason>1</idSeason>
</episodeview>
<episodeview>
    <idShow>1</idShow>
    <idSeason>1</idSeason>
</episodeview>
</episodeview>

And my php file:

<?php
$idShow = "1";
$source = "show.xml";

$xmlstr = file_get_contents($source);
$xmlcont = new SimpleXMLElement($xmlstr);
foreach($xmlcont as $url) {
    if ($url->idShow == $idShow) {
        $test = $url->idSeason;
        echo "Season ";
        echo $test;
        echo "<br>";
     }      
}

?>

Answer 1

try this, short and sweet:

 $xml=simplexml_load_file($source); // (1)

 foreach ($xml->xpath("//idSeason") As $season) { // (2)

      $s[(int)$season]=$season; // (3)
 }

 foreach ($s As $a) echo "Season $a<br />"; // (4)

1. get a simplexml -Element from the file

2. select the <idSeason> -nodes only using xpath and iterate through them

3. create a new array $s with the season-id as index and as value --> an array-index has to be unique, so duplicate ids won't enlarge the array, but "overwrite" the index if it already existed.

4. iterate through $s to echo it

I am aware that one could select only unique values by xpath , but I'm not that skilled ;-) and simplexml is not supporting xpath 2.0 which is easier.

Answer 2

Try:

<?php
$idShow = "1";
$source = "show.xml";
$have = array();

$xmlstr = file_get_contents($source);
$xmlcont = new SimpleXMLElement($xmlstr);
foreach($xmlcont as $url) {
    if ($url->idShow == $idShow) {
        $test = $url->idSeason;
         if( ! in_array( $test, $have) ){ //Check if the season already is displayed
           echo "Season ";
           echo $test;
           echo "<br>";
           $have[] = $test; //Store the season in the array
          }
     }      
}

This way you store everything you displayed in the array, and before you output test, it checkes if it is displayed already.

Answer 3

I'd go about it like this:

<?php
  $idShow = "1";
  $source = "show.xml";

  $xmlstr  = file_get_contents($source);
  $xmlcont = new SimpleXMLElement($xmlstr);
  $seasons = array();
  foreach($xml_cont as $url){ $seasons[] = $url->idSeason; }

  $seasons = array_uniq($seasons);

  foreach($seasons as $season){ echo "Season $season <br />"; } 
?>

Granted, my example involves more looping than some other solutions you might try, but I'd argue that it's fairly efficient, and perhaps just as importantly, readable.