2nd Update: In attempt to provide a comprehensive answer, I am benchmarking the three methods proposed in the various answers.
var testURL = '/Products/List?SortDirection=dsc&Sort=price&Page=3&Page2=3';
var i;
// Testing the substring method
i = 0;
console.time('10k substring');
while (i < 10000) {
testURL.substring(0, testURL.indexOf('?'));
i++;
}
console.timeEnd('10k substring');
// Testing the split method
i = 0;
console.time('10k split');
while (i < 10000) {
testURL.split('?')[0];
i++;
}
console.timeEnd('10k split');
// Testing the RegEx method
i = 0;
var re = new RegExp("[^?]+");
console.time('10k regex');
while (i < 10000) {
testURL.match(re)[0];
i++;
}
console.timeEnd('10k regex');
Results in Firefox 3.5.8 on Mac OS X 10.6.2:
10k substring: 16ms
10k split: 25ms
10k regex: 44ms
Results in Chrome 5.0.307.11 on Mac OS X 10.6.2:
10k substring: 14ms
10k split: 20ms
10k regex: 15ms
Note that the substring method is inferior in functionality as it returns a blank string if the URL does not contain a querystring. The other two methods would return the full URL, as expected. However it is interesting to note that the substring method is the fastest, especially in Firefox.
1st UPDATE: Actually the split() method suggested by Robusto is a better solution that the one I suggested earlier, since it will work even when there is no querystring:
var testURL = '/Products/List?SortDirection=dsc&Sort=price&Page=3&Page2=3';
testURL.split('?')[0]; // Returns: "/Products/List"
var testURL2 = '/Products/List';
testURL2.split('?')[0]; // Returns: "/Products/List"
Original Answer:
var testURL = '/Products/List?SortDirection=dsc&Sort=price&Page=3&Page2=3';
testURL.substring(0, testURL.indexOf('?')); // Returns: "/Products/List"