1、关于NSString的方法
官方提供的方法：
/* In the enumerate methods, the blocks will be invoked inside an autorelease pool, so any values assigned inside the block should be retained.
*/
- (void)enumerateSubstringsInRange:(NSRange)range options:(NSStringEnumerationOptions)opts usingBlock:(void (^)(NSString * __nullable substring, NSRange substringRange, NSRange enclosingRange, BOOL *stop))block NS_AVAILABLE(10_6, 4_0);
- (void)enumerateLinesUsingBlock:(void (^)(NSString *line, BOOL *stop))block NS_AVAILABLE(10_6, 4_0);
// 字符串
NSString *filePath = [[NSBundle mainBundle] pathForResource:@"girl" ofType:@"txt"];
NSData *fileData = [NSData dataWithContentsOfFile:filePath];
NSString *fileStr = [[NSString alloc]initWithData:fileData encoding:NSUTF8StringEncoding];
//一行一行的读取
[fileStr enumerateLinesUsingBlock:^(NSString * _Nonnull line, BOOL * _Nonnull stop) {
NSLog(@"%@\n",line);
}];
// 一个字符一字符的读取
[fileStr enumerateSubstringsInRange:NSMakeRange(0, fileStr.length) options:NSStringEnumerationByWords usingBlock:^(NSString * _Nullable substring, NSRange substringRange, NSRange enclosingRange, BOOL * _Nonnull stop) {
NSLog(@"tmp111===%@",substring);
}];
2、关于NSArray的方法的使用
官方提供的方法：
- (void)enumerateObjectsUsingBlock:(void (^)(ObjectType obj, NSUInteger idx, BOOL *stop))block NS_AVAILABLE(10_6, 4_0);
- (void)enumerateObjectsWithOptions:(NSEnumerationOptions)opts usingBlock:(void (^)(ObjectType obj, NSUInteger idx, BOOL *stop))block NS_AVAILABLE(10_6, 4_0);
- (void)enumerateObjectsAtIndexes:(NSIndexSet *)s options:(NSEnumerationOptions)opts usingBlock:(void (^)(ObjectType obj, NSUInteger idx, BOOL *stop))block NS_AVAILABLE(10_6, 4_0);
NSArray *tmpAry = @[@"1",@"2",@"3"];
/**
NSEnumerationConcurrent 当前的排序状态
NSEnumerationReverse 倒序排列
*/
[tmpAry enumerateObjectsWithOptions:NSEnumerationReverse usingBlock:^(id _Nonnull obj, NSUInteger idx, BOOL * _Nonnull stop) {
NSLog(@"tmpAry===%@\n",obj);
}];
3、关于NSDictionary的方法的使用
官方方法：
- (void)enumerateKeysAndObjectsUsingBlock:(void (^)(KeyType key, ObjectType obj, BOOL *stop))block NS_AVAILABLE(10_6, 4_0);
- (void)enumerateKeysAndObjectsWithOptions:(NSEnumerationOptions)opts usingBlock:(void (^)(KeyType key, ObjectType obj, BOOL *stop))block NS_AVAILABLE(10_6, 4_0);
// 字典
NSDictionary *tmpdic = @{@"1":@"q",@"2":@"w"};
[tmpdic enumerateKeysAndObjectsUsingBlock:^(id _Nonnull key, id _Nonnull obj, BOOL * _Nonnull stop) {
NSLog(@"tmpdis:key=%@ value=%@\n",key,obj);
}];
/**
NSEnumerationConcurrent 当前的排序状态
NSEnumerationReverse 倒序排列
*/
[tmpdic enumerateKeysAndObjectsWithOptions:NSEnumerationReverse usingBlock:^(id _Nonnull key, id _Nonnull obj, BOOL * _Nonnull stop) {
NSLog(@"tmpdis2:key=%@ value=%@\n",key,obj);
}];