复制代码 代码如下:

+ (id)studentWithFirstName:(NSString *)firstName lastName:(NSString *)lastName{ 
     
    Student *stu = [[Student alloc] init]; 
     
    stu.firstName = firstName; 
    stu.lastName = lastName; 
     
    return stu; 
} 
 
+ (id)studentWithFirstName:(NSString *)firstName lastName:(NSString *)lastName bookName:(NSString *)bookName{ 
 
    Student *stu = [Student studentWithFirstName:firstName lastName:lastName]; 
     
    stu.book = [Book bookWithName:bookName]; 
     
    return stu; 
 
} 
 
- (NSComparisonResult)compareStudent:(Student *)stu{ 
     
    NSComparisonResult result = [self.firstName compare:stu.firstName]; 
     
    if (result == NSOrderedSame) { 
        result = [self.lastName compare:stu.lastName]; 
    } 
     
    return result; 
     
} 
 
- (NSString *)description{  
  
    //return [NSString stringWithFormat:@\" %@ %@ %@\",self.firstName,self.lastName,self.book.name]; 
    return [NSString stringWithFormat:@\" %@ %@ %@\",self.firstName,self.lastName,_book.name]; 
} 
 
 
#pragma mark 3.NSArray排序1 
void arraySort1(){ 
     
    NSArray *array = [NSArray arrayWithObjects:@\"2\",@\"3\",@\"1\",@\"4\", nil nil]; 
     
    // 指定系统自带规定的比较方法compare: 
    NSArray *array2 = [array sortedArrayUsingSelector:@selector(compare:)]; 
    NSLog(@\"%@\",array2); 
     
} 
 
#pragma mark 3.NSArray排序2 
void arraySort2(){  
      
    Student *stu1 = [Student studentWithFirstName:@\"hu\" lastName:@\"mingtao\"]; 
    Student *stu2 = [Student studentWithFirstName:@\"zhu\" lastName:@\"wenpeng\"]; 
    Student *stu3 = [Student studentWithFirstName:@\"zhao\" lastName:@\"weisong\"]; 
    Student *stu4 = [Student studentWithFirstName:@\"hu\" lastName:@\"junpeng\"]; 
     
    NSArray *array = [NSArray arrayWithObjects:stu1,stu2,stu3,stu4, nil nil]; 
     
    // 类似JAVA中得compareTo,自己定义比较方式,但是一定要实现compare方法 
    NSArray *array2 = [array sortedArrayUsingSelector:@selector(compareStudent:)]; 
     
    NSLog(@\"%@\",array2); 
 
} 
 
#pragma mark 3.NSArray排序3-Block排序 
void arraySort3(){ 
     
    Student *stu1 = [Student studentWithFirstName:@\"hu\" lastName:@\"mingtao\"]; 
    Student *stu2 = [Student studentWithFirstName:@\"zhu\" lastName:@\"wenpeng\"]; 
    Student *stu3 = [Student studentWithFirstName:@\"zhao\" lastName:@\"weisong\"]; 
    Student *stu4 = [Student studentWithFirstName:@\"hu\" lastName:@\"junpeng\"]; 
     
    NSArray *array = [NSArray arrayWithObjects:stu1,stu2,stu3,stu4, nil nil]; 
     
    NSArray *array2 = [array sortedArrayUsingComparator:^NSComparisonResult(Student *obj1, Student *obj2) { 
        NSComparisonResult result = [obj1.firstName compare:obj2.firstName]; 
         
        if (result == NSOrderedSame) { 
            result = [obj1.lastName compare:obj2.lastName]; 
        }  
          
        return result; 
    }]; 
     
    NSLog(@\"%@\",array2); 
 
     
}  
 
#pragma mark 4.NSArray排序4-高级排序 
void arraySort4(){ 
     
    Student *stu1 = [Student studentWithFirstName:@\"hu\" lastName:@\"mingtao\" bookName:@\"lianai\"]; 
    Student *stu2 = [Student studentWithFirstName:@\"zhu\" lastName:@\"wenpeng\" bookName:@\"tianshi\"]; 
    Student *stu3 = [Student studentWithFirstName:@\"zhao\" lastName:@\"weisong\" bookName:@\"love\"]; 
    Student *stu4 = [Student studentWithFirstName:@\"hu\" lastName:@\"junpeng\" bookName:@\"qingren\"]; 
     
    NSArray *array = [NSArray arrayWithObjects:stu1,stu2,stu3,stu4, nil nil]; 
     
    // 1.先按照书名进行排序 
    NSSortDescriptor *bookNameDesc = [NSSortDescriptor sortDescriptorWithKey:@\"book.name\" ascending:YES]; 
    // 2.先按照姓进行排序 
    NSSortDescriptor *firstNameDesc = [NSSortDescriptor sortDescriptorWithKey:@\"firstName\" ascending:YES]; 
    // 3.先按照名进行排序 
    NSSortDescriptor *lastNameDesc = [NSSortDescriptor sortDescriptorWithKey:@\"lastName\" ascending:YES]; 
 
    NSArray *array2 = [array sortedArrayUsingDescriptors:[NSArray arrayWithObjects:bookNameDesc,firstNameDesc,lastNameDesc, nil nil]]; 
     
    NSLog(@\"%@\",array2);  
      
     
}

复制代码 代码如下:

#pragma mark - NSArray的基本用法
   // 创建一个空数组
      NSArray *array = [NSArray array];
   // 创建有一个元素的数组
      array = [NSArray arrayWithObject:@\"123\"];
    // 创建有多个元素的数组
      array = [NSArray arrayWIthObjects:@\"a\",@\"b\",nil ];//不能装nil空指针，空值代表数组元素结束
    // 将一个数组赋值给一个数组
    + (instancetype)arrayWithArray:(NSArray *)array;
    // 获取元素的个数
       int count = [array count]; //和 count = array.count; 相同，都是调用get方法
    // 是否包含一个元素
      - (bool)containsObject:(id)anObject;
    // 返回最后一个元素
       - (id) lastObject;
     // 获取index位置的元素
        - (id)objectAtIndex:(NSUInteger) index;
     // 获取元素的位置
        - (NSUInteger) indexOfObject:(id)anObject;
     // 在range范围内查找元素的位置
        - (NSUInteger) indexofObject:(id)anObject inRange:(NSRange)range;
     // 比较两个集合内容是否相同
        - (Bool) isEqualToArray:(NSArray *)otherArray;
     // 返回两个集合中第一个相同的对象元素
        - (id) firstObjectCommonWithArray:(NSArray *)otherArray;