Passing value to JS function through URL on window load

Question

my page http://www.dinomuhic.com/2010/index.php loads the Showreel at the start of the page using an onLoad call in body like this:

Answer 1

You can use RegExp to accomplish this, read the url parameters and pass them to ajax.

this simple script will read the current url and pass through regex to filter for paramters you specify.

• EG: ThisReq = gip('sndReq'); pulls sndReq and value from the url.

---

<script language="javascript">
    function gip(name) {
        name = name.replace(/[\[]/, "\\\[").replace(/[\]]/, "\\\]");
        var regexS = "[\\?&]" + name + "=([^&#]*)";
        var regex = new RegExp(regexS);
        var results = regex.exec(window.location.href);
        if (results == null)
            sndReq('96');
         else
            return results[1];
    }
    // parameter pulled from url.
    ThisReq = gip('sndReq');
    // executes function sndReq();
    sndReq(''+ThisReq+'');
</script>

---

Answer 2

if you are using jQuery, why not use the DOM-ready handler instead of onload ? on that note, if it's just an ajax request, you don't even need to wait for DOM-ready. if you parse the query, you should be able to pass that in to your existing function.

// Wait for DOM-ready, may not be needed if you are just
// making a request, up to you to decide :)
$(function() {
    // window.location.search represents the query string for
    // current URL, including the leading '?', so strip it off.
    var query = window.location.search.replace(/^\?/, "");

    // If there is no query, default to '96'
    if ( !query ) {
        query = '96';
    }

    // Call existing function, passing the query value
    sndReq( query );
});

hope that helps! cheers.

Answer 3

You need to parse the query string. I find the easiest way to deal with the query string is to do the following. First, you need to extract the query string from the URL:

var queryStr = window.location.search; // will give you ?sndReq=234

Then, you can strip out the ? and split each query string parameter into an array:

var paramPairs = queryStr.substr(1).split('&');

Now you can build a hash table object of the name/value pairs making up the query string:

var params = {};
for (var i = 0; i < paramPairs.length; i++) {
    var parts = paramPairs[i].split('=');
    params[parts[0]] = parts[1];
}

In your onload, you can now use the parameter thusly:

sndReq(params.sndReq);

Make sure that the code is run within a script in the head of your document so that it's computed before the onload is executed.