Let's assume I have the string:
"I love visiting http://www.google.com"
How can I detect the token, http://www.google.com?
You can use NSDataDetectors These were added in iOS4 and are quite useful. You want to create a data detector with the NSTextCheckingTypeLink and let it do its thing.
NSString *testString = #"Hello http://google.com world";
NSDataDetector *detect = [[NSDataDetector alloc] initWithTypes:NSTextCheckingTypeLink error:nil];
NSArray *matches = [detect matchesInString:testString options:0 range:NSMakeRange(0, [testString length])];
NSLog(#"%#", matches);
You could do something like:
-(BOOL)textIsUrl:(NSString*)someString {
NSPredicate *predicate = [NSPredicate predicateWithFormat:#"SELF MATCHES ^[-a-zA-Z0-9#:%_\\+.~#?&//=]{2,256}\\.[a-z]{2,4}\\b(\\/[-a-zA-Z0-9#:%_\\+.~#?&//=]*)?$"];
[predicate evaluateWithObject:someString];
}
Related
i am trying to check if NSString is in specific format. dd:dd:dd. I was thinking of NSRegularExpression. Something like
/^(\d)\d:\d\d:\d\d)$/ ?
Have you tried something like:
NSError *error = NULL;
NSRegularExpression *regex = [NSRegularExpression regularExpressionWithPattern:#"^\d{2}:\d{2}:\d{2}$"
options:0
error:&error];
NSUInteger numberOfMatches = [regex numberOfMatchesInString:string
options:0
range:NSMakeRange(0, [string length])];
(I haven't tested it, because I cannot right now, but it should be working)
I suggest to use RegexKitLite
With this and assuming that in dd:dd:dd 'd' actually stands for a digit from 0-9 it should be fairly easy to implement what you need given the additional comment from Grijesh.
Here's an example copied from the RegexKitLite page:
// finds phone number in format nnn-nnn-nnnn
NSString *regEx = #"{3}-[0-9]{3}-[0-9]{4}";
NSString *match = [textView.text stringByMatching:regEx];
if ([match isEqual:#""] == NO) {
NSLog(#"Phone number is %#", match);
} else {
NSLog(#"Not found.");
}
UPDATE:
NSString *idRegex = #"[0-9][0-9]:[0-9][0-9]:[0-9][0-9]";
NSPredicate *idTest = [NSPredicate predicateWithFormat:#"SELF MATCHES %#", idRegex];
for (NSString * str in newArrAfterPars) {
if ([idTest evaluateWithObject:str]) {
}
}
Basically I'm looking for a good example of matching HTML (also newlines and whitespace) using NSRegularExpression.
I have this PHP code I wrote a while back:
preg_match_all("/<dt>(.+?)<\/dt>\W+<dd>(.+?)<\/dd>/si", $data, $m['deets']);
Now I know this works in PHP but for the life of me I can't translate it to Objective-C. Here was my attempt.
NSRegularExpression *regex = [NSRegularExpression regularExpressionWithPattern:#"<dt>(.+?)<\/dt>\W+<dd>(.+?)<\/dd>" options:(NSRegularExpressionCaseInsensitive) error:&error];
return [regex matchesInString:target options:NSCaseInsensitiveSearch range:NSMakeRange(0, [target length])];
My target in this case is a bunch of HTML.
I never used NSRegularExpression, but NSPredicate instead :
NSError *error = NULL;
NSString* pattern = #"/<dt>(.+?)<\/dt>\W+<dd>(.+?)<\/dd>/si";
NSPredicate* predicate = [NSPredicate predicateWithFormat:#"SELF MATCHES %#", pattern];
if ([predicate evaluateWithObject:myTargetString] == YES) {
// Okay
} else {
// Not found
}
Hope this helps.
EDIT :
NSPredicate is cool, be don't work if you want to get the matching range of your target string.
Your code is right, but the problem comes from the regexp expression, you must escape your \ characters and not escape / ones.
#"<dt>(.+?)</dt>\\W+<dd>(.+?)</dd>"
So :
NSRegularExpression *regex = [NSRegularExpression regularExpressionWithPattern:#"<dt>(.+?)</dt>\\W+<dd>(.+?)</dd>" options:(NSRegularExpressionCaseInsensitive) error:&error];
return [regex matchesInString:target options:NSCaseInsensitiveSearch range:NSMakeRange(0, [target length])];
I would like to be able to take the numbers lying behind the ` symbol and in front of any character that is non-numerical and convert it into a integer.
Ex.
Original String: 2*3*(123`)
Result: 123
Original String: 4`12
Result: 4
Thanks,
Regards.
You can use regular expressions. You can find all the occurrences like this:
NSString *mystring = #"123(12`)456+1093`";
NSRegularExpression *regex = [NSRegularExpression regularExpressionWithPattern:#"([0-9]+)`" options:0 error:nil];
NSArray *matches = [regex matchesInString:mystring options:0 range:NSMakeRange(0, mystring.length)];
for (NSTextCheckingResult *match in matches) {
NSLog(#"%#", [mystring substringWithRange:[match rangeAtIndex:1]]);
}
// 12 and 1093
If you only need one occurrence, then replace the for loop with the following:
if (matches.count>0) {
NSTextCheckingResult *match = [matches objectAtIndex:0];
NSLog(#"%#", [mystring substringWithRange:[match rangeAtIndex:1]]);
}
There can be better way to do this, Quickly i could come up with this,
NSString *mystring = #"123(12`)";
NSString *neededString = nil;
NSScanner *scanner =[NSScanner scannerWithString:mystring];
[scanner scanUpToString:#"`" intoString:&neededString];
neededString = [self reverseString:neededString];
NSLog(#"%#",[self reverseString:[NSString stringWithFormat:#"%d",[neededString intValue]]]);
To reverse a string you can see this
I have this string:
<td align="right"><span> 19:45 </span></td>
I want to use a NSPredicate on it to search for the 19:45 part but every possible combination I tried returns nothing! I'm kinda losing my marbles here so please help!
Things i've tried:
NSString *timeStringPredicate = #"[0-9]:[0-9]";
NSPredicate *timeSearch = [NSPredicate predicateWithFormat:#"SELF like %#", timeStringPredicate];
if ([timeSearch evaluateWithObject:dayText]) {
NSLog(#"This is a time");
}
Or in these possibilities:
NSString *timeStringPredicate = #"[0-9]\\:[0-9]";
NSString *timeStringPredicate = #"*[0-9]:[0-9]*";
NSString *timeStringPredicate = #"*[0-9]\\:[0-9]*";
NSString *timeStringPredicate = #"*.[0-9]:[0-9].*";
NSString *timeStringPredicate = #"*.[0-9]\\:[0-9].*";
And about everything else.
Help!
like doesn't use regexp syntax. For that, you need to use matches instead. See The Predicate Programming Guide for details.
NSString *timeStringPredicate = #".*\\:[0-9].*";
NSPredicate *timeSearch = [NSPredicate predicateWithFormat:#"SELF matches %#", timeStringPredicate];
Try to do this:
NSString *timeStringPredicate = #".*\\:[0-9].*";
NSPredicate *timeSearch = [NSPredicate predicateWithFormat:#"SELF matches '%#'", timeStringPredicate];
I'm building a NSPredicate using the code below for an iPhone app. The logging shows the prediate to be: location CONTAINS "head" AND shape CONTAINS "oval" AND texture CONTAINS "bumpy" AND colour CONTAINS "red"
I get no results. If I limit the predicate to a single item it will work, more than 1 fails.
Can anyone tell me why?
Many thanks
NSMutableArray *subPredicates = [[NSMutableArray alloc] init];
for (Ditem in self.tableDataSource) {
NSString *Title = [Ditem valueForKey:#"Title"];
NSString *Value = [Ditem valueForKey:#"Value"];
if([[Value lowercaseString] isEqualToString: #"all"]){
Value = #"";
}
else{
NSPredicate *p = [NSComparisonPredicate predicateWithLeftExpression:[NSExpression expressionForKeyPath:[Title lowercaseString]] rightExpression:[NSExpression expressionForConstantValue:[Value lowercaseString]] modifier:NSDirectPredicateModifier type:NSContainsPredicateOperatorType options:0];
[subPredicates addObject:p];
}
}
NSPredicate *predicate = [NSCompoundPredicate andPredicateWithSubpredicates:subPredicates];
NSLog(#"predicate: %#", predicate);[self.fetchedResultsController.fetchRequest setPredicate:predicate];
Your predicate is requiring that all of the values in your filterable objects be strings. Is that correct?
Also, I would simplify your subpredicate creation to:
NSPredicate * p = [NSPredicate predicateWithFormat:#"%K CONTAINS %#", [Title lowercaseString], [Value lowercaseString]];