PHP- Decode JSON

2019-01-08 02:43发布

问题:

I have the following script to get search results from an API and then slice the array and dump it, I am having trouble decoding the JSON into an array, it returns Array(0) { } It is a wordpress shortcode

Here is a sample of the Json that is gotten from the api:

[
  {
    "barcode": "000015426950",
    "name": "Karen's cowboy",
    "author": "Ann",
    "author_last": "Martin",
    "publisher": "New York : Scholastic, c2000.",
    "year_pub": "",
    "edition": "",
    "genre": "",
    "checkout": "out",
    "series": "",
    "callnum": "MAR",
    "fiction": "true",
    "in_house": "false",
    "timestamp": "1355835387",
    "outto": "000008388615",
    "duedate": "1372005722",
    "ISBN": "059052528X",
    "media_type": "",
    "print": "false",
    "BOXID": "2147483647",
    "uid": "10",
    "printed": ""
  },
  {
    "barcode": "000015426949",
    "name": "Karen's yo-yo",
    "author": "Ann M",
    "author_last": "Martin",
    "publisher": "New York : Scholastic, c2000.",
    "year_pub": "",
    "edition": "",
    "genre": "",
    "checkout": "out",
    "series": "",
    "callnum": "MAR",
    "fiction": "true",
    "in_house": "false",
    "timestamp": "1355835343",
    "outto": "000008388615",
    "duedate": "1373216918",
    "ISBN": "0590525115",
    "media_type": "",
    "print": "false",
    "BOXID": "",
    "uid": "10",
    "printed": ""
  },
...
  }
]

Here is the code used to get the JSON and paginate it,:

function book_search_form() {
?>
<form method='get'><input type='text' name='searchvalue' value='<? if (isset($_GET['searchvalue'])) echo $_GET['searchvalue'];?>' />&nbsp;<input type='submit' value='Search' /><input type='hidden' name='pagenum' value='1' /></form>
<br>
<?php 
if(isset($_GET['pagenum']) && isset($_GET['searchvalue']))
{
$page=$_GET['pagenum'];
$searchvalue = $_GET['searchvalue'];   // get the value of the page from your url
$recordsPerPage=10; // number of records you want on your page
$api_url = get_option('api_url');
    $api_key = get_option('api_key');
    $data = file_get_contents("$api_url/book/index.php/name/$searchvalue?key=2513619352");
    $array = (array)json_decode($data);

$index=($page*$recordsPerPage)-1;
$recordsToBeDisplayed = array_slice($array,$index,$recordsPerPage);// this array contains all the records you would want to display on a page;



    $total_pages=ceil(count($array)/$recordsPerPage);
    }
else { 

//use default values

}
?>
<html>...<body><div id="records">
<?
echo '<pre>';
echo $recordsToBeDisplayed;
echo '</pre>';?><!-- use the array created above to display records -->
    </div>
<div id="pagination">
<?
for($j=1;$j<=$total_pages;$j++){
                    if($j==$page)
                   {?>

                   <li style="display: inline;"><a href="?searchvalue=&pagenum=<?=$j?>"><u><?=$j?></u></a></li>
                   <?}else{?>
                        <li style="display: inline;"><a href="?searchvalue=&pagenum=<?=$j?>"><?=$j?></a></li>


                   <?}}?>
</div>
<?php


}

回答1:

Try json_decode

$array = json_decode($data, true);

Then you'll get an array instead of an object.

Example #1 json_decode() examples

<?php
$json = '{"a":1,"b":2,"c":3,"d":4,"e":5}';

var_dump(json_decode($json));
var_dump(json_decode($json, true));

?>

The above example will output:

object(stdClass)#1 (5) {
    ["a"] => int(1)
    ["b"] => int(2)
    ["c"] => int(3)
    ["d"] => int(4)
    ["e"] => int(5)
}

array(5) {
    ["a"] => int(1)
    ["b"] => int(2)
    ["c"] => int(3)
    ["d"] => int(4)
    ["e"] => int(5)
}


回答2:

Separate your php from html please, use indentation and:

$array = json_decode($data, TRUE); //second param used for associative array return

Example #1 json_decode() examples
<?php
$json = '{"a":1,"b":2,"c":3,"d":4,"e":5}';

var_dump(json_decode($json));
var_dump(json_decode($json, true));

?>
The above example will output:
object(stdClass)#1 (5) {
    ["a"] => int(1)
    ["b"] => int(2)
    ["c"] => int(3)
    ["d"] => int(4)
    ["e"] => int(5)
}

array(5) {
    ["a"] => int(1)
    ["b"] => int(2)
    ["c"] => int(3)
    ["d"] => int(4)
    ["e"] => int(5)
}

P.S: From the Bible (http://php.net/manual/en/function.json-decode.php)



回答3:

If input is in array format then also you can use the same function json_decode. You just need to apply loop for result.

json = '{

"a1":{ "field1":"name1", "field2":age1, "field3":"country1" },

"a2":{ "field1":"name2", "field2":age2, "field3":"country2" },

"a3":{ "field1":"name3", "field2":age3, "field3":"country3" } }';

$Array = json_decode($json, true);

foreach ($Array as $key => $value)
{

    echo " $key ";

    foreach ($value as $k => $val)    
    {
        echo "$k | $val <br />";
    } 

}