Get Vimeo clip_id from url with regex in objective C - objective-c

Question

Can anybody tell me how to extract the clip_id from a Vimeo url using Obj C regex?
http://vimeo.com/moogaloop.swf?clip_id=12050952&server=vimeo.com&show_title=1&show_byline=1&show_portrait=0&color=56872c&fullscreen=1
I want to extract 12050952.
Thanks.

Answer 1

you can do it with this pattern:
(?<=clip_id=)\d+
It is using positive lookbehind.
Demo: example

Answer 2

I am using a utility class URLParser & its easy and clear.
URLParser *parser = [[[URLParser alloc] initWithURLString:url] autorelease];
NSString *videoId = [parser valueForVariable:#"clip_id"];
Here is the URLParser class
#import <Foundation/Foundation.h>
#interface URLParser : NSObject {
NSArray *variables;
}
#property (nonatomic, retain) NSArray *variables;
- (id)initWithURLString:(NSString *)url;
- (NSString *)valueForVariable:(NSString *)varName;
#end
#implementation URLParser
#synthesize variables;
- (id) initWithURLString:(NSString *)url{
self = [super init];
if (self != nil) {
NSString *string = url;
NSScanner *scanner = [NSScanner scannerWithString:string];
[scanner setCharactersToBeSkipped:[NSCharacterSet characterSetWithCharactersInString:#"&?"]];
NSString *tempString;
NSMutableArray *vars = [NSMutableArray new];
[scanner scanUpToString:#"?" intoString:nil]; //ignore the beginning of the string and skip to the vars
while ([scanner scanUpToString:#"&" intoString:&tempString]) {
[vars addObject:[tempString copy]];
}
self.variables = vars;
[vars release];
}
return self;
}
- (NSString *)valueForVariable:(NSString *)varName {
for (NSString *var in self.variables) {
if ([var length] > [varName length]+1 && [[var substringWithRange:NSMakeRange(0, [varName length]+1)] isEqualToString:[varName stringByAppendingString:#"="]]) {
NSString *varValue = [var substringFromIndex:[varName length]+1];
return varValue;
}
}
return nil;
}
- (void) dealloc{
self.variables = nil;
[super dealloc];
}
#end