1.遍历字典
NSDictionary *dictionary = @{@"name": @"jack", @"age": @"18"};
1>for (NSString *key in dictionary) {
id obj = dictionary[key];
}
2>NSArray *keyArray = [dictionary allKeys];
NSArray *valueArray = [dictionary allValues];
for (NSString *key in keyArray) {
id obj = valueArray[key];
}
3>[dictionary enumerateKeysAndObjectsUsingBlock:^(id key, id obj, BOOL *stop) {
*stop = YES;
}];
2.遍历数组
NSArray *array = @[@"jack", @"lucy"];
1>for (NSString *str in array) {
}
2>[array enumerateObjectsUsingBlock:^(id obj, NSUInteger idx, BOOL *stop) {
}];
3>迭代器遍历数组
NSEnumerator *enumerator = [array objectEnumerator];
[enumerator allObjects];//有值
id obj = nil;
while (obj = [enumerator nextObject]) {
}
[enumerator allObjects];//返回nil