CODEWITHSUNDEEP
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Sachin Sharma
Sachin Sharma

Reputation: 184

Trying to make the QR code automatic by using random value generated by a function from php

Hi this is my code working fine when you type the text it gets converted into an qr code but i want to make it automatic. I have a php function which generates random number, so instead of typing the text, the qrcode should be generated by the value of that function.

enter image description here

This is my html page code:

    <!DOCTYPE html>
<body>
  <input id="text" type="text" value="http" style="width:80%" /><br />
<div id="qrcode"></div>
  <script src='http://cdnjs.cloudflare.com/ajax/libs/jquery/2.1.3/jquery.min.js'></script>
<script src='http://davidshimjs.github.com/qrcodejs/qrcode.min.js'></script>

    <script src="js/index.js"></script>

</body>
</html>

This is my javascript function :

var qrcode = new QRCode("qrcode");

function makeCode () {      
    var elText = <?php echo random_str(6); ?> ;

    if (!elText.value) {
        alert("Input a text");
        elText.focus();
        return;
    }

    qrcode.makeCode(elText.value);

}

makeCode();

$("#text").
    on("blur", function () {
        makeCode();
    }).
    on("keydown", function (e) {
        if (e.keyCode == 13) {
            makeCode();
        }
    });

and this is the php function that i want to implement so that an random number will generate and qrcode will be formed on that basis

<?php

function random_str($length, $keyspace = '0123456789')
{
    $str = '';
    $max = mb_strlen($keyspace, '8bit') - 1;
    for ($i = 0; $i < $length; ++$i) {
        $str .= $keyspace[random_int(0, $max)];
    }
  return $str;
}

?>

Upvotes: 2

Views: 1932

Answers (2)

Sofiane Achouba
Sofiane Achouba

Reputation: 604

It depends on how your html is rendered

1- if it's from php and you this function is in same file or can be called from this php file, you can do that:

<script>
var qrcode = new QRCode("qrcode");
qrcode.makeCode('<?php echo random_str(3); ?>');
</script>

2- if it's an html file you can not call the function, you can use ajax to call a php file which give you the value of random and use it

Upvotes: 1

Vanquished Wombat
Vanquished Wombat

Reputation: 9525

When you were using the input-based version you coded the makeCode() function to pull the value for the QRCode from the input box. Now that you are using a literal value you need to modify the makeCode() in respect of how it works with the source number - now a javascript literal value and not a control.

function makeCode () {      
    var elText = "<?php echo random_str(6); ?>" ; // note quotes around random no.

    if (elText.length === 0) { // is the random string zero length 
        alert("Random number is blank - weird !");
        return;
    }

    qrcode.makeCode(elText);

}

The quotes around the random number from php will protect you from the risk of it returning a blank. I don't know how likely that is but if it did happen then the JS would fail. And since there are no numeric operations on it we can just treat it as a string. In that case we can test it's length and decide from there is we need to make the QRCode.

Upvotes: 2

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