1.截取两个指定字符串中的字符串
NSString *string = @"abavavasdsvx,as.dsf/,.[abcdefghijklmn]dgdfg";
NSRange start = [string rangeOfString:@"["];
NSRange end = [string rangeOfString:@"]"];
NSString *sub = [string substringWithRange:NSMakeRange(start.location, end.location-start.location+1)];
NSLog(@"sub=%@",sub);
控制台就输出:[abcdefghijklmn]
2.字符串截取到第n位 （substringToIndex: n）（第n 位不算再内）
- （void）viewDidLoad
{
NSString *a = ＠"i like long dress";
NSString *b = [a substringToIndex:4];
NSLog（＠"\n b: ％＠"，b）;
控制台输出： b: i li
3.字符串从第n 位开端截取，直到最后 （substringFromIndex:n）（包含第 n 位）
- （void）viewDidLoad
{
NSString *a = ＠"i like long dress";
NSString *b = [a substringFromIndex:4];
NSLog（＠"\n b: ％＠"，b）;
}
控制台输出： b: ke long dress
}
4.根据下标截取字符串
NSString*string =@"sdfsfsfsAdfsdf";
string = [string substringToIndex:7];//截取掉下标7之后的字符串
NSLog(@"截取的值为：%@",string);
[string substringFromIndex:2];//截取掉下标2之前的字符串
NSLog(@"截取的值为：%@",string);
5.匹配字符串
NSString*string =@"sdfsfsfsAdfsdf";
NSRangerange = [stringrangeOfString:@"f"];//匹配得到的下标
NSLog(@"rang:%@",NSStringFromRange(range));
string = [string substringWithRange:range];//截取范围类的字符串
NSLog(@"截取的值为：%@",string);
6.分隔字符串
NSString*string =@"sdfsfsfsAdfsdf";
NSArray *array = [string componentsSeparatedByString:@"A"]; //从字符A中分隔成2个元素的数组
NSLog(@"array:%@",array); //结果是adfsfsfs和dfsdf
7、替换字符串
例如：将字符串中所有带有“-”的字符，都替换成“→”，然后将其更改颜色
NSString *pointStr = @"→";
NSString *trafficStr = @"要我知道-你还得-等放假恩发-第三方的-的发热及";
NSString *strUrl = [trafficStr stringByReplacingOccurrencesOfString:@"-" withString:pointStr]; //这里就是替换字符串
NSArray *trafficArr = [trafficStr componentsSeparatedByString:@"-"]; //这里是通过将字符串中“-”拆分成一个数组里
NSMutableAttributedString *strP = [[NSMutableAttributedString alloc]initWithString:strUrl];
NSInteger rangeMin = 0;
int i = 0;
NSMutableArray *tempArr = trafficArr.mutableCopy;
[tempArr removeLastObject];
for (NSString *tempstr in tempArr) {
NSInteger tempStrLenth = tempstr.length;
rangeMin += tempStrLenth;
NSRange range = {rangeMin+i,1}; // 这里是遍历拆分好的数组中每一个字符串，从而得知要替换的“-”的下标位置
NSLog(@"range%lu , %d",(unsigned long)range.location, i);
[strP addAttribute:NSForegroundColorAttributeName value:[UIColor colorWithHexString:@"#23beae"] range:range];
[strP addAttribute:NSFontAttributeName value:[UIFont systemFontOfSize:20] range:range];
i++;
cell.traffic.attributedText = strP;
}