如何使用php将新节点写入服务器上的json文件

Question

How can i handle an array sent by jquery to put into an existing nested json file with php? I can send the data with jquery but all i can manage is php overwriting the file or adding the data to the end of the document, i need to put new data in the nested structure of the json file.

My script looks like this;

<?php
$postdata = $_POST['data'];
$postdata = json_encode($postdata);
file_put_contents('json/user.json', $postdata);
?>

My json had a nested structure like;

"{\"users\":
    [{\"user\":
         [{\"id\":\"martijn\",
           \"pw\":\"password\",
           \"name\":\"user3\",
           \"icons\":
              [{\"bookmarks\":\"bookmark3\",
                \"notes\":\"note3\"
           }]
         }]
    }]
}"

I would like to add another user to the users, how would i do that with php?

My jQuery request and the data to send;

var newUser = [{
                    user: [{
                        id: username,
                        pw: password,
                        name: "user3",
                        icons: [{
                            bookmarks: "bookmark3",
                            notes: "note3"
                        }]
                    }]
                }];


                var userSetup = JSON.stringify(newUser);

                $.ajax({
                    url: themeUrl + '/script.php',
                    type: 'POST',
                    data: { 
                        data: newUser,
                    },
                    dataType: 'json'
                });

Answer 1

This a bit tricky situation,

You need to make use of these steps inorder to do that..

• First check if the file user.json exists by using file_exists()
• If it does.. Just read all the content from it using the file_get_contents()
• Now json_decode() it and store that in an array.
• Now grab the $_POST['data'] and add it to the earlier decoded array.
• Now you have to do the final json_encode() it to a string.
• Finally write to the user.json file using file_put_contents() . [No need of the FILE_APPEND flag]

The coding part...

<?php 

if(file_exists('json/user.json'))
{
$cont = file_get_contents('json/user.json'); 
$usr_array = json_decode($cont,1);
    foreach($_POST['data'] as $val)
    {
        $usr_array[]=$val;
    }
$newData = json_encode($usr_array); 
file_put_contents('json/user.json', $newData ); 
}
else
{
    die('File does not exist !');
}