oc数组遍历

#import <Foundation/Foundation.h>

//数组遍历（枚举）对集合中的元素依此不重复的进行遍历

int main(int argc, const char * argv[]) {

@autoreleasepool {

NSArray *arr=@[@"MON",@"TUE",@"WED",@"THU",@"FRI",@"SAT",@"SUN"];

//下标遍历

for (int i=0; i<[arr count]; i++) {

NSString *element=[arr objectAtIndex:i];

NSLog(@"%@",element);

}

NSLog(@"\n");

for (int i=0; i<[arr count]; i++) {

NSLog(@"%@",arr[i]);

}

NSLog(@"\n");

//for in 遍历性高

for (NSString *str in arr) {

NSLog(@"%@",str);

}

NSLog(@"\n");

//id当 不确定数组元素的类型时，选择使用de

//id NSObject instancetype

for (id str in arr) {

NSLog(@"%@",str);

}

}

return 0;

}