iOS模型输出和打印

在调试时,我们经常用到输出model,查看数据是否正确,还会在控制台"po 模型"操作,一般输出都是这样的格式的:

person is <Person: 0x608000034300>

这里添加一种解决方法:

1> 解决NSLog(@"person is %@", p)打印model内容:

//
//  Person.m
//  Demo1
//
//  Created by 思 彭 on 2017/7/31.
//  Copyright © 2017年 思 彭. All rights reserved.
//

#import "Person.h"
#import <objc/runtime.h>

@implementation Person

// 通过重写模型的description方法,实现打印Model

- (NSString *)description {
    
    // 初始化一个字典
    NSMutableDictionary *dictionary = [NSMutableDictionary dictionary];
    // 得到当前classs的所有属性
    uint count;
    objc_property_t *properties = class_copyPropertyList([self class], &count);
    for (int i = 0; i < count; i++) {
        // 循环并用kvc得到每个属性的值
        objc_property_t property = properties[i];
        NSString *name = @(property_getName(property));
        id value = [self valueForKey:name] ? : nil;  // 默认值为nil字符串
        [dictionary setObject:value forKey:name];
    }
    // 释放
    free(properties);
    // return
    return [NSString stringWithFormat:@"<%@: %p> -- %@",[self class], self, dictionary];
}
@end

2>po model输出model内容:

//
//  NSObject+DebugDescription.m
//  Demo1
//
//  Created by 思 彭 on 2017/7/31.
//  Copyright © 2017年 思 彭. All rights reserved.
//

#import "NSObject+DebugDescription.h"
#import <objc/runtime.h>

@implementation NSObject (DebugDescription)

- (NSString *)debugDescription {
    if ([self isKindOfClass:[NSArray class]] || [self isKindOfClass:[NSNumber class]] || [self isKindOfClass:[NSString class]]) {
        return  self.debugDescription;
    }
    // 初始化一个字典
    NSMutableDictionary *dictionary = [NSMutableDictionary dictionary];
    // 得到当前classs的所有属性
    uint count;
    objc_property_t *properties = class_copyPropertyList([self class], &count);
    for (int i = 0; i < count; i++) {
        // 循环并用kvc得到每个属性的值
        objc_property_t property = properties[i];
        NSString *name = @(property_getName(property));
        id value = [self valueForKey:name] ? : nil;  // 默认值为nil字符串
        [dictionary setObject:value forKey:name];
    }
    // 释放
    free(properties);
    // return
    return [NSString stringWithFormat:@"<%@: %p> -- %@",[self class], self, dictionary];
}

@end

使用:

//
//  ViewController.m
//  Demo1
//
//  Created by 思 彭 on 2017/7/31.
//  Copyright © 2017年 思 彭. All rights reserved.
//

#import "ViewController.h"
#import "Person.h"
#import "NSObject+DebugDescription.h"

@interface ViewController ()

@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
    
    Person *p = [Person new];
    p.name = @"sis";
    p.age = 30;
    p.habit = @"singer, dancer";
    NSLog(@"person is %@", p);  // person is <Person: 0x608000034300>
}


- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}


@end

注意:

在使用控制器类需要导入该Category哟!!!