Question

I have a jquery function which on submit event is generating an url.If one the parameter is not defined, adding to url should be skipped

        var category        =$("#prod_category").val();
        var group           =$("#prod_group")
        window.location.href = "/page/" +
            **//add to url if category is definned**
        encodeURI(category) + "/" +
            **//add to url if group is definned**       
        encodeURI(group) + "/" +

Answer 1

You can simply state if (category). If category has a value with a length greater than zero, this will return true.

var url = "/page/";
if (category){
  url = url + encodeURI(category) + "/";
}
if (group){
  url = url + encodeURI(group) + "/";
}

EDIT: When setting the values to category and group ensure you trim any whitespace that the element may be containing. For example:

var category = $.trim($("#prod_category").val());