How do I split a URL by the / character?
For example,
www.stackoverflow.com/questions
I want to split after / in the above URL to get /questions
This may help you.
NSString *url = #"www.stackoverflow.com/questions";
NSArray *items = [url componentsSeparatedByString:#"/"];
NSString *str1=[items objectATindex:0]; //www.stackoverflow.com
NSString *str2=[items objectATindex:1]; //questions
Use the pathComponents property on an NSURL object.
This property contains an array containing the individual path components of the URL, each unescaped using the stringByReplacingPercentEscapesUsingEncoding: method. For example, in the URL file:///directory/directory%202/file, the path components array would be #[#"/", #"directory", #"directory 2", #"file"].
NSURL *myUrl = [NSURL URLWithString:#"www.stackoverflow.com/questions"];
NSString *lastPathComponent = [myUrl lastPathComponent]; // "questions"
NSArray *pathComponents = [myUrl pathComponents]; // <__NSArrayM 0x7fc45b649df0>( www.stackoverflow.com, questions )
To remove the http://, use host property:
NSURL *myUrl = [NSURL URLWithString:#"http://www.stackoverflow.com/questions"];
NSString *host = myUrl.host; // stackoverflow.com
Related
I've got a small problem that seems a little bit odd to me. I often used NSString or NSLog while adding NSNumbers into several places:
NSNumber *categoryId = [[NSNumber alloc]initWithInt:0];
NSURL *url = [NSURL URLWithString:#"http://shop.rs/api/json.php?action=getCategoryByCategory&category=%i",[categoryId integerValue]];
Now xcode tells me that I'm too many arguments. What am I doing wrong? Setting up an NSNumber into NSStrings or NSLogs works as I did it above.
Best Regards
What is wrong is on
NSURL *url = [NSURL URLWithString:#"http://shop.rs/api/json.php?action=getCategoryByCategory&category=%i",[categoryId integerValue]];
you are calling URLWithString: and then pass in a string that is not being formatted correctly. If you want to do it all on one line then you need to be using stringWithFormat: like
NSURL *url = [NSURL URLWithString:[NSString stringWithFormat:#"http://shop.rs/api/json.php?action=getCategoryByCategory&category=%i",[categoryId integerValue]]];
Because it is adding a parameter you can't just create a string like you normally would with #"some text" you need to format it using the stringWithFormat: which will return an NSString * with the text held within #"" and the paramters you pass in. So [NSString stringWithFormat:#"My String will come with %#", #"Apples"]; this would provide an NSString with "My String will come with Apples". For more information check out the Apple Documentation for NSString and stringWithFormat:
Try this :
NSURL *url = [NSURL URLWithString:[NSString stringWithFormat:#"http://shop.rs/api/json.phpaction=getCategoryByCategory&category=%i", [categoryId integerValue]]];
Initially code was wrong because of : "categoryId integerValue]" (I forgot a '[').
You can use NSString to form your NSURL. You can then pass it to your URLWithString like below:
NSNumber *categoryId = [NSNumber numberWithInteger:0];
NSString *urlString = [NSString stringWithFormat:#"http://shop.rs/api/json.php?action=getCategoryByCategory&category=%i",[categoryId integerValue]];
NSURL *url = [NSURL URLWithString:urlString];
my url is https://photos.googleapis.com/data/upload/resumable/media/create-session/feed/api/user/111066158452258/albumid/60281009241807
i want to extract the value of user & albumid, i had tried to extract with different methods which i found in stack overflow ,but they didn't work.
Please help me out.
Thank you for your precious time.
You can take your NSURL (or init one from the URL string), and use the method pathComponents which return an array of the words in the URL (separated from the slash /), so:
pathComponents[0] == #"photos.googleapis.com"
pathComponents[1] == #"data"
...etc.
Here the snippet of code:
NSURL *url = [NSURL urlWithString:#"https://photos.googleapis.com/data/upload/resumable/media/create-session/feed/api/user/111066158452258/albumid/60281009241807"];
NSString *user = url.pathComponents[9];
NSString *album = url.pathComponents[11];
I give you an example here, NSURL class is your friend. You can use e.g. pathComponents: to get an array of all components and then process this array as you need it:
NSURL *url = [NSURL URLWithString:#"https://photos.googleapis.com/data/upload/resumable/media/create-session/feed/api/user/111066158452258/albumid/60281009241807"];
NSArray *components = [url pathComponents];
NSLog(#"path components: %#", components);
NSLog(#"user: %#", components[9]);
NSLog(#"albumid: %#", components[11]);
NSURL *url = [NSURL URLWithString:#"https://photos.googleapis.com/data/upload/resumable/media/create-session/feed/api/user/111066158452258/albumid/60281009241807"];
NSArray *pathComponentsArray = [url pathComponents];
NSString*userValue;
NSString*albumidValue;
for(int i=0;i<[pathComponentsArray count];i++)
{
if([pathComponentsArray[i] isEqualToString:#"user"])
{
userValue = pathComponentsArray[i+1];
}
if([pathComponentsArray[i] isEqualToString:#"albumid"])
{
albumidValue = pathComponentsArray[i+1];
}
}
I have a UISearchBar from which I'm extracting the text that represents an address and building from it a JSON URL for Google Geocoder.
NSString* address = searchbar.text;
NSString* url = [NSString stringWithFormat:#"http://maps.google.com/maps/api/geocode/json?address=%#&sensor=false", address];
If I copy & paste the url from debug window to the browser it works like a charm but when I try to convert it to NSURL i get nil
NSURL* theUrl = [NSURL URLWithString:url];
Any ideas?
I added the encoding to the address prior to concatenating the url and that fixed the problem so now the code looks like this:
NSString* address = searchbar.text;
NSString *encodedString = (NSString *)CFBridgingRelease(CFURLCreateStringByAddingPercentEscapes(NULL, CFBridgingRetain(address), NULL, (CFStringRef)#"!*'();:#&=+$,/?%#[]", kCFStringEncodingUTF8));
NSString* url = [NSString stringWithFormat:#"http://maps.google.com/maps/api/geocode/json?address=%#&sensor=false", encodedString];
I used this code from the Stack Overflow question: URLWithString: returns nil:
//localisationName is a arbitrary string here
NSString* webName = [localisationName stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
NSString* stringURL = [NSString stringWithFormat:#"http://maps.google.com/maps/geo?q=%#,Montréal,Communauté-Urbaine-de-Montréal,Québec,Canadae&output=csv&oe=utf8&sensor=false", webName];
NSString* webStringURL = [stringURL stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
NSURL* url = [NSURL URLWithString:webStringURL];
When I copied it into my code, there wasn't any issue but when I modified it to use my url, I got this issue:
Data argument not used by format string.
But it works fine. In my project:
.h:
NSString *localisationName;
.m:
NSString* webName = [localisationName stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
NSString* stringURL = [NSString stringWithFormat:#"http://en.wikipedia.org/wiki/Hősök_tere", webName];
NSString* webStringURL = [stringURL stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
NSURL* url = [NSURL URLWithString:webStringURL];
[_webView loadRequest:[NSURLRequest requestWithURL:url]];
How can I solve this? Anything missing from my code?
The # in the original string is used as a placeholder where the value of webName is inserted. In your code, you have no such placeholder, so you are telling it to put webName into your string, but you aren't saying where.
If you don't want to insert webName into the string, then half your code is redundant. All you need is:
NSString* stringURL = #"http://en.wikipedia.org/wiki/Hősök_tere";
NSString* webStringURL = [stringURL stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
NSURL* url = [NSURL URLWithString:webStringURL];
[_webView loadRequest:[NSURLRequest requestWithURL:url]];
The +stringWithFormat: method will return a string created by using a given format string as a template into which the remaining argument values are substituted. And in the first code block, %# will be replaced by value of webName.
In your modified version, the format parameter, which is #"http://en.wikipedia.org/wiki/Hősök_tere", does not contain any format specifiers, so
NSString* stringURL = [NSString stringWithFormat:#"http://en.wikipedia.org/wiki/Hősök_tere", webName];
just runs like this (with the warning Data argument not used by format string.):
NSString* stringURL = #"http://en.wikipedia.org/wiki/Hősök_tere";
I have a string
https://gdata.youtube.com/feeds/api/videos?q=4s-PbMuNooo
I want to get string 4s-PbMuNooo. How do I parse a NSString?
Short answer :
NSString *myString = #"https://gdata.youtube.com/feeds/api/videos?q=4s-PbMuNooo";
NSArray *components = [myString componentsSeparatedByString:#"="];
NSString *query = [components lastObject];
Problems :
1) What if the bit after the q= contains another =
2) What if the q= bit is missing?
A better answer is for you to read the documentation - there are lots of helper methods on NSString that will get you substrings. Look for rangeOfString to find out where the equals would be and subStringWithRange to get the bit you want.
EDIT: Thomas has raised a fair point about URL parsing - see his answer here
A slightly longer but more complete answer. Hope this helps:
NSURL *url = [NSURL URLWithString: #"https://gdata.youtube.com/feeds/api/videos?param1=yeah¶m2="];
NSArray *listItems = [[url query] componentsSeparatedByString:#"&"];
NSMutableDictionary *keyValues = [NSMutableDictionary dictionaryWithCapacity:listItems.count];
for (NSString *item in listItems) {
NSArray *keyValue = [item componentsSeparatedByString:#"="];
NSAssert(keyValue.count == 2, #"Key value pair mismatch");
[keyValues setObject:[keyValue objectAtIndex:1] forKey:[keyValue objectAtIndex:0]];
}
NSLog(#"1: %#", [keyValues objectForKey:#"param1"]);
NSLog(#"2: %#", [keyValues objectForKey:#"param2"]);
Like this:
NSArray *listItems = [yourString componentsSeparatedByString:#"="];
NSString *myFinalString=[NSString stringWithString:[listItems objectAtIndex:1]];
I wanted to try this a bit, so here is my code that handles more than one parameters:
NSURL *url = [NSURL URLWithString:#"https://gdata.youtube.com/feeds/api/videos?p=123123&q=234"];
NSArray *queryArray = [[url query] componentsSeparatedByString:#"&"];
for (NSString *queryString in queryArray) {
NSArray *queryComponents = [queryString componentsSeparatedByString:#"="];
if ([[queryComponents objectAtIndex:0] isEqualToString:#"q"]) {
NSLog(#"Found q: %#", [queryString substringFromIndex:2]);
} else {
NSLog(#"Did not find q.");
}
}
The question and its title are badly chosen - the answers are generally right for the more general task of splitting ANY string up, but bad for splitting up URLs as this question is actually about.
Here's how to properly get the values from a URL:
To break up a URL string, first do this:
NSURL *url = [NSURL URLWithString:urlString];
Then retrieve the parameters (the part past the "?") like this:
NSString *query = [url query];
Now you can go ahead and split that query string up using componentsSeparatedByString:#"&" as shown in the other answers.