ios - 简单的 stringByReplacingOccurrencesOfString 帮助问题

Question

我想将字符串中的一些“非法”字符替换为另一个“合法”字符，我有以下代码:

- (NSString *) quitarTildes:(NSString *)aStr
{
    NSString *aux = aStr;
    NSString *invalid = @"áéíóúÁÉÍÓÚñÑ";
    NSString *valid = @"aeiouAEIOUnN";
    for (int i = 0; i < [invalid length]; i++)
        [aux stringByReplacingOccurrencesOfString: [NSString stringWithFormat:@"%c",[invalid characterAtIndex:i]] 
                                       withString: [NSString stringWithFormat:@"%c",[valid characterAtIndex:i]]];
    NSLog(@"%@",aux);
    return aux;
}

所有非法字符仍然存在...

NSString *test = @"Hólá, Ésto es una prueba.";
test = [self quitarTildes: test];

NSLog，响应:

2013-04-04 08:58:52.896 GeoRuta_v1[1960:907] Hólá, Ésto es una prueba.

Answer 1

来自文档:

stringByReplacingOccurrencesOfString:withString: Returns a new string in which all occurrences of a target string in the receiver are replaced by another given string.

-(NSString *)stringByReplacingOccurrencesOfString:(NSString *)target withString:(NSString *)replacement

所以:

aux = [aux stringByReplacingOccurrencesOfString: [NSString stringWithFormat:@"%c",[invalid characterAtIndex:i]] 
                                       withString: [NSString stringWithFormat:@"%c",[valid characterAtIndex:i]]];