how to get value from url parameter using javascript or jquery

Question

I have an issue in getting value from url, I have a link which shows up a modal as I have

<a href='#modal?userId=<%=resultSet.getInt("drid")%>' class="button-border toggleModal">Apportionment</a>

above link opens up the modal is given below

<div id="modal" class="modal"> 
 <header>
 <h2>Appointment Form</h2> 
 </header>
 <form action="addappoinment.jsp" method="post">
 <input type="hidden" id="docId" name="docid" value=""><br>
 <input type="text" required><br>
 <input type="text" required><br>
 <input type="text" required><br>
 <input type="text" required><br>
 <textarea rows="4" cols="21"></textarea><br> 
 <button class="button-border button-success" type="submit">
 Done</button>
 <button class="button-border button-error pull-right toggleModal">
 Cancel</button> 
 </form> 
 </div>

Now I have a url like

http://localhost:8080/app/#modal?userId=1

now I want to get value of userId parameter using the javascript

<script type="text/javascript">
function getParameterByName(name) {
 name = name.replace(/[\[]/, "\\[").replace(/[\]]/, "\\]");
 var regex = new RegExp("[\\?&]" + name + "=([^&#]*)"),
 results = regex.exec(location.search);
 return results === null ? "" : decodeURIComponent(results[1].replace(/\+/g, " "));
}
var param = getParameterByName("userId");
var userId = document.getElementById("docId");
userId.value = param;
</script>

but can not be able to get value from http://localhost:8080/app/#modal?userId=1

• John Hascall: You want the #modal to be after the ?userId=blah part. More on how URLs are constructed is here: stackoverflow.com/questions/13386209/…
• Jack A.: The getParameterByName function doesn't work because the data you are looking for is in the fragment (everything after the #), not in the query string. Usually, this approach is used by single page application frameworks (e.g., AngularJS). Are you using such a framework? If so, it may provide methods to retrieve the information you need.

Answer 1

#modal?userId=1

The query string (which is sent to the server) has to go before the fragment identifier (which is handled entirely client side).

i.e.

?userId=1#modal

If you don't want to send that data to the server, then you need to read the fragment identifier (location.hash) and split it on the ? to get the piece you need.

• Quentin: @LogicalError — If you don't know how to split a javascript string than Google can help.

Answer 2

Use the jquery url parser plugin:

$.url().param('userId');

EDIT: If you have the URL in a string, you can do:

$.url('http://localhost:8080/app/#modal?userId=1').param('userId'); // returns '1'

EDIT 2: This works:

$.url($.url('http://localhost:8080/app/#modal?userId=1').fsegment(1)).param('userId')) //returns '1'

• Quentin: That parses query strings. The data isn't in a query string.
• MojoJojo: @Quentin: Fixed code.Thanks for pointing out. The '#' was causing a problem.

Answer 3

function getUrlParams() { 
 var url = window.location
 var inputParam = 'DBName'//input parameter 
 var params = url.split('?'); 
 var b = params[1].split('&'); 
 for (i=0; i<b.length; i++){
 var c= b[i].split('=');
 if (c[0] == inputParam){
 alert(c[1]);//return the parameter value
 break;
}

• mrun: A piece of advice: some explanations would significantly improve the quality of your answer.