CSV to JSON with PHP?

Question

I need to convert a CSV file to JSON on the server using PHP. I am using this script which works:

function csvToJSON($csv)          


        

Answer 1

I recommend using Coseva (a csv parsing library) and using the built in toJSON() method.

<?php

// load
require('../src/CSV.php');

// read
$csv = new Coseva\CSV('path/to/my_csv.csv');

// parse
$csv->parse();

// disco
echo $csv->toJSON();

Answer 2

I modified the answer in the question to use the first line of the CSV for the array keys. This has the advantage of not having to hard-code the keys in the function allowing it to work for any CSV with column headers and any number of columns.

Here is my modified version:

function csvToJson($csv) {
    $rows = explode("\n", trim($csv));
    $data = array_slice($rows, 1);
    $keys = array_fill(0, count($data), $rows[0]);
    $json = array_map(function ($row, $key) {
        return array_combine(str_getcsv($key), str_getcsv($row));
    }, $data, $keys);

    return json_encode($json);
}

Answer 3

None of these answers work with multiline cells, because they all assume a row ends with '\n'. The builtin fgetcsv function understands that multiline cells are enclosed in " so it doesn't run into the same problem. The code below instead of relying on '\n' to find each row of a csv lets fgetcsv go row by row and prep our output.

function csv_to_json($file){

    $columns = fgetcsv($file); // first lets get the keys.
    $output = array(); // we will build out an array of arrays here.

    while(!feof($file)){ // until we get to the end of file, we'll pull in a new line
        $line = fgetcsv($file); // gets the next line
        $lineObject = array(); // we build out each line with our $columns keys
        foreach($columns as $key => $value){
            $lineObject[$value] = $line[$key];
        }
        array_push($output, $lineObject);
    }
    return json_encode($output); // encode it as json before sending it back
}

Answer 4

You could probably reduce the overhead by removing all the spaces and \n's. But that's in your note.

You could increase the performance by skipping the preg_replace and passing a boolean that would turn it on and off.

Other than that, the variable unrolling of your var[1-10] actually is good, as long as there are always ten varaibles.

The explode and the foreach approach are just fine.

Answer 5

Some tips...

• If you have URL opening enabled for fopen() and wrappers, you can use fgetscsv().
• You can build an array of the CSV, and then convert it with PHP's native json_encode().
• The correct mime type for JSON is application/json.

Answer 6

Well there is the json_encode() function, which you should use rather than building up the JSON output yourself. And there is also a function str_getcsv() for parsing CSV:

$array = array_map("str_getcsv", explode("\n", $csv));
print json_encode($array);

You must however adapt the $array if you want the JSON output to hold named fields.