数组字符串之间相互转化

// 字符串转数组：
NSString *str = @'a,b,c,d,e,f';
NSArray *array = [str componentsSeparatedByString:@','];
// 数组转字符串：
NSArray *array1 = @[@'a',@'b',@'c',@'d'];
NSString *str1 = [array1 componentsJoinedByString:@','];
NSLog(@'array = %@', array);
NSLog(@'str1 = %@', str1);