How to remove the content before '>' and after space in objective C?

Question

Here is the example:

<aNodeName thsisjijdsnjdnjsd>, and I would like to remove thsisjijdsnjdnjsd,

How can I detect the string which is before the > and after the space , and trim out it in objective C? Also, please remind that I don't know the aNodeName or thsisjijdsnjdnjsd, because the data may turn out something like this:

<anotherNodeName zxzxxzxzxz>, and I need to remove zxzxxzxzxz.

http://stackoverflow.com/questions/1732348/regex-match-open-tags-except-xhtml-self-contained-tags - trust me on this — Kate Gregory, Oct 19 '12 at 21:56
@KateGregory — we dont know, if this is meant for html parsing. But note, that I added the link you provided as warning in my answer, in case it is meant for html-parsing. — vikingosegundo, Oct 20 '12 at 16:38

score 1 · Accepted Answer · edited May 23 '17 at 11:56

Basically you have two options

Regular expressions

NSString *string = @"<aNodee thsisjijdsnjdnjsd>";
NSError *error;
NSRegularExpression *regex = [NSRegularExpression regularExpressionWithPattern:@"<(\\S+)( .*)>" options:NSRegularExpressionCaseInsensitive
                                                                         error:&error];
NSArray *matches = [regex matchesInString:string options:0 range:NSMakeRange(0, [string length])];
[matches enumerateObjectsUsingBlock:^(NSTextCheckingResult *result, NSUInteger idx, BOOL *stop) {
    NSString* nodeName = [string substringWithRange:[result rangeAtIndex:1]];
    NSString* value = [string substringWithRange:[result rangeAtIndex:2]];
    NSLog(@"%@ %@",nodeName, value);
}];

Note, that you shouldn't parse complex html with Regular Expressions.

NSScanner

NSScanner *scanner = [NSScanner scannerWithString:string];
BOOL recordingValue = NO;

NSMutableString *valueString = [@"" mutableCopy];
[scanner setScanLocation:0];
while (![scanner isAtEnd]) {

    NSString *charAtlocation = [string substringWithRange:NSMakeRange([scanner scanLocation], 1)];
    if ([charAtlocation isEqualToString:@" "]){
        recordingValue = YES;
        [valueString appendString:@" "];
    } else{
        if ([charAtlocation isEqualToString:@">"]){
            recordingValue = NO;
        } else if (recordingValue) {
            [valueString appendString:charAtlocation];
        }
    }
    [scanner setScanLocation:[scanner scanLocation]+1];
} ;


NSLog(@"Scanner approach: %@", valueString);
NSLog(@"Scanner approach: %@", [string stringByReplacingOccurrencesOfString:valueString withString:@""]);

Complete command line based example

#import <Foundation/Foundation.h>

int main(int argc, const char * argv[])
{

    @autoreleasepool {
        NSString *string = @"<aNodee thsisjijdsnjdnjsd> ";
        NSError *error;
        NSRegularExpression *regex = [NSRegularExpression regularExpressionWithPattern:@"<([a-zA-z]+)( .*)>" options:NSRegularExpressionCaseInsensitive
                                                                                 error:&error];
        NSArray *matches = [regex matchesInString:string options:0 range:NSMakeRange(0, [string length])];
        [matches enumerateObjectsUsingBlock:^(NSTextCheckingResult *result, NSUInteger idx, BOOL *stop) {
            NSString* nodeName = [string substringWithRange:[result rangeAtIndex:1]];
            NSString* value = [string substringWithRange:[result rangeAtIndex:2]];
            NSLog(@"Regex approach: %@ %@",nodeName, value);

            NSLog(@"Regex approach: %@", [string stringByReplacingOccurrencesOfString:value withString:@""]);
        }];




        NSScanner *scanner = [NSScanner scannerWithString:string];
        BOOL recordingValue = NO;

        NSMutableString *valueString = [@"" mutableCopy];
        [scanner setScanLocation:0];
        while (![scanner isAtEnd]) {

            NSString *charAtlocation = [string substringWithRange:NSMakeRange([scanner scanLocation], 1)];
            if ([charAtlocation isEqualToString:@" "]){
                recordingValue = YES;
                [valueString appendString:@" "];
            } else{
                if ([charAtlocation isEqualToString:@">"]){
                    recordingValue = NO;
                } else if (recordingValue) {
                    [valueString appendString:charAtlocation];
                }
            }
            [scanner setScanLocation:[scanner scanLocation]+1];
        } ;


        NSLog(@"Scanner approach: %@", valueString);
        NSLog(@"Scanner approach: %@", [string stringByReplacingOccurrencesOfString:valueString withString:@""]);
    }
    return 0;
}

Output:

Regex approach: aNodee  thsisjijdsnjdnjsd
Regex approach: <aNodee> 
Scanner approach:  thsisjijdsnjdnjsd
Scanner approach: <aNodee>

Updated the question, I don't have the knowledge that I know the `aNodeName` — DNB5brims, Oct 18 '12 at 02:37

How to remove the content before '>' and after space in objective C?

1 Answers1