Objective-c – Create NSString by repeating another string a given number of times

cocoaobjective cstring

This should be easy, but I'm having a hard time finding the easiest solution.

I need an NSString that is equal to another string concatenated with itself a given number of times.

For a better explanation, consider the following python example:

>> original = "abc"
>> times = 2
>> result = original * times

Any hints?


I was going to post a solution similar to the one by Mike McMaster's answer, after looking at this implementation from the OmniFrameworks:

// returns a string consisting of 'aLenght' spaces
+ (NSString *)spacesOfLength:(unsigned int)aLength;
static NSMutableString *spaces = nil;
static NSLock *spacesLock;
static unsigned int spacesLength;

if (!spaces) {
spaces = [@"                " mutableCopy];
spacesLength = [spaces length];
    spacesLock = [[NSLock alloc] init];
if (spacesLength < aLength) {
    [spacesLock lock];
    while (spacesLength < aLength) {
        [spaces appendString:spaces];
        spacesLength += spacesLength;
    [spacesLock unlock];
return [spaces substringToIndex:aLength];

Code reproduced from the file:


on the OpenExtensions framework from the Omni Frameworks by The Omni Group.

Best Answer

There is a method called stringByPaddingToLength:withString:startingAtIndex::

[@"" stringByPaddingToLength:100 withString: @"abc" startingAtIndex:0]

Note that if you want 3 abc's, than use 9 (3 * [@"abc" length]) or create category like this:

@interface NSString (Repeat)

- (NSString *)repeatTimes:(NSUInteger)times;


@implementation NSString (Repeat)

- (NSString *)repeatTimes:(NSUInteger)times {
  return [@"" stringByPaddingToLength:times * [self length] withString:self startingAtIndex:0];