ios 开发 OC编程 块语法bolck
//
// main.m
// oc- 07 block
//
// Created by dllo on 15/11/3.
// Copyright (c) 2015年 dllo. All rights reserved.
//
//void test(void)
//{
// printf("hanshu");
//}
#import <Foundation/Foundation.h>
#import "Student.h"
NSInteger glB = 5;
//全局变量的声明 1, 全部大写 2, 加gl
typedef void (^blockType)(void);
int main(int argc, const char * argv[]) {
// void (*p)(void) = test;
//block语法
//block1- block名字
//block的实现在方法内部
// void (^block1)(void) = ^(void) {
// NSLog(@"block1");
// };
//
//调用
// block1();
//练习1 创建block,实现打印指定次数的block2
//练习2 创建block,分别实现加减乘除
//练习3 创建block, 分别判断某个数字是否为偶数
//练习4 写一个返回值为整形,参数为NSString(仅一个参数)的block,实现将字符型转换为整形的功能
//提高题,创建学生类,分别编写block判断2名学生的分数,年龄,姓名的大小
//1
// void(^block)(NSInteger a)= ^(NSInteger a) {
// for (NSInteger i = 0; i < a; i++) {
// NSLog(@"block2");
//
// }
//
// };
// block(4);
//2
// int(^block2)(int a, int b) = ^(int a, int b) {
// return a + b;
// };
//
// int(^block3)(int a, int b) = ^(int a, int b) {
// return a - b;
// };
// int(^block4)(int a, int b) = ^(int a, int b) {
// return a * b;
// };
// int(^block5)(int a, int b) = ^(int a, int b) {
// return a / b;
// };
// int ret = block2(4,3);
// NSLog(@"%d", ret);
// int ret1 = block3(4,3);
// NSLog(@"%d", ret1);
// int ret2 = block4(4,3);
// NSLog(@"%d", ret2);
// int ret3 = block5(4,3);
// NSLog(@"%d", ret3);
// //3
// BOOL(^block6)(int a) = ^(int a) {
// if (0 == a % 2) {
// BOOL ret = YES;
// return ret;
// } else
// return NO;
//
// };
// NSLog(@"%d", block6(4));
// //4
// NSInteger(^block7)(NSString *) = ^(NSString *a) {
// NSInteger b = [a intValue];
// return b;
// };
// NSInteger b = block7(@"234");
// NSLog(@"%ld",b);
//提高
// Student *stu1 = [[Student alloc]initWithName:@"yuhao" age:21 score:99];
// Student *stu2 = [[Student alloc]initWithName:@"laoda" age:23 score:59];
// Student *stu3 = [[Student alloc]initWithName:@"zy" age:22 score:56];
// NSMutableArray *arr = [NSMutableArray arrayWithObjects:stu1, stu2, stu3, nil];
//
// NSComparisonResult(^compareName)(NSString *, NSString *) = ^(NSString *a, NSString *b) {
// return [a compare:b];
// };
// compareName(stu1.name, stu2.name);
// NSComparisonResult(^compareAge)(NSInteger, NSInteger)= ^(NSInteger a, NSInteger b) {
// if (a > b) {
//
// return NSOrderedAscending;
// if (a < b) {
// return NSOrderedDescending;
// }
// return NSOrderedSame;
//
//
// }
// };
//
// compareAge(stu1.age, stu2.age);
// void(^comparescore)(NSInteger,NSInteger) = ^(NSInteger a, NSInteger b) {
// NSLog(@"较大值是%ld", a > b ? a : b);
// };
// comparescore(stu1.score, stu2.score);
//初级版本
// NSComparisonResult(^comparName)(id, id) = ^NSComparisonResult(id s1, id s2 ) {
// Student *stu1 = (Student *)s1;
// Student *stu2 = (Student *)s2;
// return [stu1.name compare: stu2.name];
//
// };
// [arr sortUsingComparator:comparName];
//究极版本 执行后的数组已经按照要求排好序
// 比较名字
// [arr sortUsingComparator:^NSComparisonResult(id obj1, id obj2) {
// Student *stu1 = (Student *)obj1;
// Student *stu2 = (Student *)obj2;
// return [stu1.name compare:stu2.name];
//
// }];
//比较分数
// [arr sortUsingComparator:^NSComparisonResult(id obj1, id obj2) {
// Student *stu1 = (Student *)obj1;
// Student *stu2 = (Student *)obj2;
// if (stu1.score > stu2.score) {
// return NSOrderedAscending ;
//
// }
// if (stu1.score < stu2.score) {
// return NSOrderedDescending;
// }
// return NSOrderedSame;
//
// }];
// for (Student *a in arr) {
// NSLog(@"%@ %ld %ld",[a name], [a age], [a score] );
// }
//比较年纪(升序)
// [arr sortUsingComparator:^NSComparisonResult(id obj1, id obj2) {
// Student *st1 = (Student *)obj1;
// Student *st2= (Student *)obj2;
// if (st1.age < st2.age) {
// return NSOrderedAscending;
// }
// if (st1.age > st2.age) {
// return NSOrderedDescending;
// }
// return NSOrderedSame;
//
// }];
// for (Student *c in arr) {
// NSLog(@"%@ %ld %ld", [c name], [c age], [c score]);
// }
//对上面的数组1 按照年纪升序排列, 按照年纪降序.按照姓名降序 ,按照姓名升序
//年纪降序
// [arr sortUsingComparator:^NSComparisonResult(id obj1, id obj2) {
// Student *st1 = (Student *)obj1;
// Student *st2 = (Student *)obj2;
// if(st1.age < st2.age) {
// return NSOrderedDescending;
// }
// if(st1.age > st2.age) {
// return NSOrderedAscending;
// }
// return NSOrderedSame;
//
// }];
// for (Student *c in arr) {
// NSLog(@"%@ %ld %ld", [c name], [c age], [c score]);
// }
//名字升序
// [arr sortUsingComparator:^NSComparisonResult(id obj1, id obj2) {
// Student *st1 = (Student *)obj1;
// Student *st2= (Student *)obj2;
// return [st1.name compare:st2.name];
// }];
// for (Student *c in arr) {
// NSLog(@"%@ %ld %ld", [c name], [c age], [c score]);
// }
//名字降序
// [arr sortUsingComparator:^NSComparisonResult(id obj1, id obj2) {
// Student *st1 = (Student *)obj1;
// Student *st2= (Student *)obj2;
// return -[st1.name compare:st2.name];
// }];
// for (Student *c in arr) {
// NSLog(@"%@ %ld %ld", [c name], [c age], [c score]);
// }
// block与变量
//block 与局部变量: 1, 只读局部变量; 2, 若想修改,可在局部变量定义处加__block声明
//block与全局变量: 1, 可以读可以写, 可运算
__block NSInteger a = 3;
blockType blocktest = ^(void) {
glB = 4;
a = 5;
NSLog(@"%ld",a);
NSLog(@"%ld", glB);
};
blockTest();
return 0;
}
//
// Student.h
// oc- 07 block
//
// Created by dllo on 15/11/3.
// Copyright (c) 2015年 dllo. All rights reserved.
//
#import <Foundation/Foundation.h>
@interface Student : NSObject
@property (nonatomic, copy) NSString *name;
@property (nonatomic, assign) NSInteger age;
@property (nonatomic, assign)NSInteger score;
- (id)initWithName:(NSString *)name age:(NSInteger)age score:(NSInteger)score;
@end
//
// Student.m
// oc- 07 block
//
// Created by dllo on 15/11/3.
// Copyright (c) 2015年 dllo. All rights reserved.
//
#import "Student.h"
@implementation Student
- (id)initWithName:(NSString *)name age:(NSInteger)age score:(NSInteger)score
{
self = [super self];
if (self) {
[self setName:name];
[self setAge:age];
[self setScore:score];
}
return self;
}
@end
