use javascript to find parameter in url and then apply if then logic
I am trying to make my page perform an action only if it sees that a particular parameter is present in the url.
I essentially want the javascript code to do this:
consider an example page such as: http://www.example.com?track=yes
If a page loads that contains the parameter ‘track’ within the url, print ‘track exists’, else if the ‘track’ parameter doesn’t exist print ‘track does not exist’
This should work:
if (window.location.search.indexOf('track=yes') > -1) {
alert('track present');
} else {
alert('track not here');
}
Use something like the function from Artem’s answer in this SO post:
if (getParameterByName('track') != '') {
alert ('run track');
}
It’s not hard to split up the query string to find the relevant bits:
var path = location.substr(1), // remove ?
queryBits = path.split('&'),
parameters = {},
i;
for (i = 0 ; i < queryBits.length ; i++) {
(function() { // restrict keyval to a small scope, don't need it elsewhere
var keyval = queryBits[i].split('=');
parameters[decodeURIComponent(keyval[0])] = decodeURIComponent(keyval[1]);
}());
}
// parameters now holds all the parts of the URL as key-value pairs
if (parameters.track == 'yes') {
alert ('track exists');
} else {
alert ("it doesn't");
}
What you’re looking for is called the Query String or Query Parameter. See this function to get it w/o the use of plugins like jQuery: How can I get query string values in JavaScript?
You can use the window.location.search property:
if(/(^|&)track(&|$)/.test(window.location.search.substring(1))) {
alert('track exists!');
} else {
alert('it doesn\'t...');
}
