Multiple inputs in a Bootbox

Actually, there is a simpler way which doesn't require you to modify bootbox code.

The string you pass at the bootbox creation doesn't have to be only text: it can also be html code. That means you can include pretty much everything in the box.

To put a custom form in a bootbox, you can then create it as follow :

bootbox.confirm("<form id='infos' action=''>\
    First name:<input type='text' name='first_name' /><br/>\
    Last name:<input type='text' name='last_name' />\
    </form>", function(result) {
        if(result)
            $('#infos').submit();
});

I just made function for that, check it out - here

Usage example

bootbox.form({
    title: 'User details',
    fields: {
        name: {
            label: 'Name',
            value: 'John Connor',
            type:  'text'
        },
        email: {
            label: 'E-mail',
            type:  'email',
            value: '[email protected]'
        },
        type: {
            label: 'Type',
            type:  'select',
            options: [
                {value: 1, text: 'Human'},
                {value: 2, text: 'Robot'}
            ]
        },
        alive: {
            label: 'Is alive',
            type: 'checkbox',
            value: true
        },
        loves: {
            label: 'Loves',
            type: 'checkbox',
            value: ['bike','mom','vg'],
            options: [
                {value: 'bike', text: 'Motorbike'},
                {value: 'mom', text: 'His mom'},
                {value: 'vg', text: 'Video games'},
                {value: 'kill', text: 'Killing people'}
            ]
        },
        passwd: {
            label: 'Password',
            type: 'password'
        },
        desc: {
            label: 'Description',
            type: 'textarea'
        }
    },
    callback: function (values) {
        console.log(values)
    }
})

Create hidden div with form in HTML and inject this html to bootbox message. Snippet below.

var buttonClick = function() {
  var bootboxHtml = $('#js-exampleDiv').html().replace('js-exampleForm', 'js-bootboxForm');
  bootbox.confirm(bootboxHtml, function(result) {
    console.log($('#ex1', '.js-bootboxForm').val());
    console.log($('#ex2', '.js-bootboxForm').val());
  });
};

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<link href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css" rel="stylesheet"/>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/bootbox.js/4.4.0/bootbox.min.js"></script>

<div id="js-exampleDiv" hidden>
  <form class="js-exampleForm">
    <div class="col-sm-12">
      <input placeholder="Example placeholder 1" id="ex1" />
    </div>
    <div class="col-sm-12">
      <input placeholder="Example placeholder 2" id="ex2" />
    </div>
  </form>
</div>

<button onclick="buttonClick();">
  Open bootbox confirm dialog.
</button>

For me, this is the cleanest way to do it :

var form = $('<form><input name="usernameInput"/></form>');
bootbox.alert(form,function(){
    var username = form.find('input[name=usernameInput]').val();
    console.log(username);
});