我更喜欢这样使用正则表达式:
NSString *myString = @"this is a test";
NSString *myNewString = [myString stringByReplacingOccurrencesOfString:@"\\s"
                                     withString:@""
                                        options:NSRegularExpressionSearch
                                          range:NSMakeRange(0, [myStringlength])];
 //myNewString will be @"thisisatest"
您可以将自己设为NSString上的类别,以使生活更加轻松:
- (NSString *) removeAllWhitespace
{
    return [self stringByReplacingOccurrencesOfString:@"\\s" withString:@""
                                              options:NSRegularExpressionSearch
                                                range:NSMakeRange(0, [self length])];
}
这也是它的单元测试方法:
- (void) testRemoveAllWhitespace
{
    NSString *testResult = nil;
    NSArray *testStringsArray        = @[@""
                                         ,@"    "
                                         ,@"  basicTest    "
                                         ,@"  another Test \n"
                                         ,@"a b c d e f g"
                                         ,@"\n\tA\t\t \t \nB    \f  C \t  ,d,\ve   F\r\r\r"
                                         ,@"  landscape, portrait,     ,,,up_side-down   ;asdf;  lkjfasdf0qi4jr0213 ua;;;;af!@@##$$ %^^ & *  * ()+  +   "
                                         ];
    NSArray *expectedResultsArray   = @[@""
                                        ,@""
                                        ,@"basicTest"
                                        ,@"anotherTest"
                                        ,@"abcdefg"
                                        ,@"ABC,d,eF"
                                        ,@"landscape,portrait,,,,up_side-down;asdf;lkjfasdf0qi4jr0213ua;;;;af!@@##$$%^^&**()++"
                                        ];
    for (int i=0; i < [testStringsArray count]; i++)
    {
        testResult = [testStringsArray[i] removeAllWhitespace];
        STAssertTrue([testResult isEqualToString:expectedResultsArray[i]], @"Expected: \"%@\" to become: \"%@\", but result was \"%@\"",
                     testStringsArray[i], expectedResultsArray[i], testResult);
    }
}