jquery - adding `http://` to string if not present

Question

In my laravel app I process an external URL provided by user. Sometimes user would paste it without the http:// prefix. UI have used this question's answers: How to check URL contains http using JQuery and RegEx

I tried to use these instructions

var lnk = $('#confirmation_URL').val();
var lnk2 = $('#confirmation_URL').val();

//adding http if not present
// if (lnk && !lnk.match(/^.+:\/\/.*/)) {  // produces jQuery error
if (lnk && !lnk.match(/^http([s]?):\/\/.*/)) { // produces jQuery error

   var lnk = $('http://' + lnk2);
   console.log( "prefix http added successfully" );
}

When pasting an URL, I get this error:

jquery-2.1.4.min.js:2 Uncaught Error: Syntax error, unrecognized expression: http://laravel.com/docs/5.1/migrationsga.error @ jquery-2.1.4.min.js:2ga.tokenize @ jquery-2.1.4.min.js:2ga.select @ jquery-2.1.4.min.js:2ga @ jquery-2.1.4.min.js:2n.fn.extend.find @ jquery-2.1.4.min.js:2n.fn.init @ jquery-2.1.4.min.js:2n @ jquery-2.1.4.min.js:2(anonymous function) @ dodaj:1460n.event.dispatch @ jquery-2.1.4.min.js:3r.handle @ jquery-2.1.4.min.js:3

what i tried

The error pops out in console for both jQUery 2.14 and 3.0beta1 Just to test for silly mistakes and exclude potential causes (such as jQUery affecting the original variable) , I created two variables with identical content: lnk and lnk2.

Thank you for your suggestions.

score 3 · Accepted Answer · answered Apr 18 '16 at 05:54

3

Please try this

$('#confirmation_URL').keyup(function () {
        if (  ($(this).val().length >=5) && ($(this).val().substr(0, 5) != 'http:') && ($(this).val().substr(0, 5) != 'https') ) {
            $(this).val('http://' + $(this).val());
        }
    });

answered Apr 18 '16 at 05:54

Anbarasi

421
2
5
23

I simplified it: ` if ( ($(this).val().length >=5) && ($(this).val().substr(0, 4) != 'http') ) { $(this).val('http://' + $(this).val()); console.log('prefixed successfully'); } else { console.log('already prefixed'); }` But now upon pasting a link without `http` the IF condition always execudes the part which SHOULD be executed when link has a `http` – Peter Apr 18 '16 at 06:05
I just tried to reverse the IF condition, but I got `http://http://` as an output. Funny, but despiriting. Any guesses? – Peter Apr 18 '16 at 06:09
OK. This code finally worked: ` var lnk2 = $('#confirmation_URL').val(); if ( ($(this).val().length >=5) && ($(this).val().substr(0, 4) == 'http') ) { console.log('already prefixed'); } else { $(this).val('http://' + lnk2); console.log('prefixed successfully'); } var lnk = $(this).val();` Thank you all! – Peter Apr 18 '16 at 06:14

Gerald · Answer 2 · 2016-04-18T06:14:11.283

1

var lnk = $('#confirmation_URL').val();
var lnk2 = $('#confirmation_URL').val();

//adding http if not present
// if (lnk && !lnk.match(/^.+:\/\/.*/)) {  // produces jQuery error
if (lnk && !lnk.match(/^http([s]?):\/\/.*/)) { // produces jQuery error
   // Here produces error actually
   // lnk = $('http://' + lnk2);

   lnk = 'http://' + lnk2;
   $('#confirmation_URL').val(lnk);
   console.log( "prefix http added successfully" );
}

Updated, sorry for the mistake.

edited Apr 18 '16 at 06:14

answered Apr 18 '16 at 05:30

Gerald

888
1
7
17

this solution produces `Uncaught TypeError: lnk.val is not a function`. I have also tied `$(lnk).val('http://' + lnk2);` and other variants, but to no success. – Peter Apr 18 '16 at 05:39
Ok, problem solved by Anbarasi's workaround. Thank you for your attempt! – Peter Apr 18 '16 at 06:15
It seems that you are mixing jQuery objects and strings, `$('#confirmation_URL')` is a jQuery object, while `'http://' + ...` is a string, `$('http://' + ...)` just doesn't make sense. – Gerald Apr 18 '16 at 06:15
This is what I wrote under Aminah Nuraini's solution. I know it doesn't make sense. How transform the jQuery object into a string? – Peter Apr 18 '16 at 06:24

score 1 · Answer 3 · answered Apr 18 '16 at 05:38

1

Try create RegExp object first

regex = new RegExp('^http([s]?):\/\/.*')
if (lnk && !regex.test(lnk)) { 

   lnk.val('http://' + lnk2);
   console.log( "prefix http added successfully" );
}

answered Apr 18 '16 at 05:38

Aminah Nuraini

18,120
8
90
108

your solution seems to be a php code. Are you sure I can youe your snippet to define a RexExp in jQuery? Anyway, I still get `Uncaught TypeError: lnk.val is not a function` – Peter Apr 18 '16 at 05:46
I googled and it was for jQuery. Reading your error, it means the error is not on the regex – Aminah Nuraini Apr 18 '16 at 06:03
My understanding is that the pair `'http://' + lnk2` should be both a text string, but somehow they don't. Still no idea how to fix it. Check out the @Anbarasi solution - within it now the problem is that the IF condition is reversed. – Peter Apr 18 '16 at 06:08
Ok, problem solved by Anbarasi's workaround. Thank you for your attempt! – Peter Apr 18 '16 at 06:15

jquery - adding `http://` to string if not present

what i tried

3 Answers3