NSRange

获取子字符串的位置

- (NSRange)rangeOfString:(NSString *)aString;

根据位置获取子字符串

- (NSString *)substringWithRange:(NSRange)range;

示例：

// NSRange 用法
NSString *fatherStr = @"Apple, Banner, Orange";
NSString *subStr_1 = @"Banner";
NSRange range_1 = [fatherStr rangeOfString:subStr_1];
NSLog(@"%@", NSStringFromRange(range_1));
NSRange range_2 = NSMakeRange(0, 5);
NSString *subStr_2 = [fatherStr substringWithRange:range_2];
NSLog(@"%@", subStr_2);

输出结果：

2015-03-02 17:34:35.479 XYResponseTimeWithC[11160:303] {7, 6}
2015-03-02 17:34:35.480 XYResponseTimeWithC[11160:303] Apple