OC-todolist项目

Todo List与数据库管理的高效实现

最新推荐文章于 2022-01-08 11:44:38 发布

iteye_11790

最新推荐文章于 2022-01-08 11:44:38 发布

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本文详细阐述了如何使用Objective-C语言结合基础数据结构和面向对象编程思想，实现了一个简单但功能全面的待办事项（Todo List）管理器，并进一步将其与数据库进行集成，实现了数据的持久化存储与检索。通过自定义类结构和方法，不仅提高了代码的可读性和可维护性，还确保了数据的安全性和一致性。此外，文章还介绍了如何利用数据库管理系统的特性，如事务处理和索引优化，来提升应用的整体性能。

// Todo.h

// todolist

// Created by zz

#import <Foundation/Foundation.h>

@interface Todo : NSObject

{

NSString* subject;//主题

NSString* description;//描述

int priority;//优先级

NSDate* date;//日期

}

@property(nonatomic,copy)NSString* subject;

@property(nonatomic,copy)NSString* description;

@property(nonatomic,assign)int priority;

@property(nonatomic,copy)NSDate* date;

-(id)initwithsubject:(NSString*)_subject description:(NSString*)_description priority:(int)_priority date:(NSString*)_date;

-(void)setsubject:(NSString*)_subject;

-(void)setdescription:(NSString*)_description;

-(void)setpriority:(int)_priority;

-(void)SetDate:(NSDate*)_date;

-(void)dealloc;

- (NSString*)description;

@end

// Todo.m

// todolist

// Created by zz

#import "Todo.h"

@implementation Todo

@synthesize subject;

@synthesize description;

@synthesize priority;

@synthesize date;

-(id)initwithsubject:(NSString*)_subject description:(NSString*)_description priority:(int)_priority date:(NSString*)_date{

if(!_subject||!_description||_priority<0||!_date){

[self release];

return nil;

}

self=[super init];

if(!self){

return nil;

}

subject=[NSString stringWithString:_subject];

description=[NSString stringWithString:_description];

priority=_priority;

NSDateFormatter * dm = [[NSDateFormatter alloc]init];

[dm setDateFormat:@"yyyy-MM-dd"];

date = [dm dateFromString:_date];

return self;

}

-(void)setsubject:(NSString*)_subject{

subject=[NSString stringWithString:_subject];

}

-(void)setdescription:(NSString*)_description{

description=[NSString stringWithString:_description];

}

-(void)setpriority:(int)_priority{

priority=_priority;

}

-(void)SetDate:(NSDate*)_date{

date=[_date copy];

}

-(void)dealloc{

[super dealloc];

}

- (NSString*)description{

NSString* ns=[[NSString alloc]initWithFormat:@"subject is %@, description is %@, priority is %d,date is %@",subject,description,priority,date];

return ns;

}

@end

// Dolist.h

// todolist

// Created byzz

#import <Foundation/Foundation.h>

@class Todo;

@interface Dolist : NSObject

{

NSMutableArray* todoarray;

}

@property(nonatomic,copy)NSMutableArray* todoarray;

-(id)init;

-(void)Addtodo:(Todo*)atodo;

-(void)Removetodo:(NSInteger)index;

-(Todo *)todoatindex:(NSInteger)index;

-(NSUInteger)Count;

-(void)dealloc;

-(NSString*)description;

@end

// Dolist.m

// todolist

// Created by zz

#import "Dolist.h"

#import "Todo.h"

@implementation Dolist

@synthesize todoarray;

-(id)init{

self=[super init];

if(!self){

return nil;

}

todoarray=[[NSMutableArray alloc]init];

return self;

}

-(void)Addtodo:(Todo*)atodo{

[todoarray addObject:atodo];

}

-(void)Removetodo:(NSInteger)index{

[todoarray removeObjectAtIndex:index];

}

-(Todo *)todoatindex:(NSInteger)index{

return [todoarray objectAtIndex:index];

}

-(NSUInteger)Count{

return [todoarray count];

}

-(void)dealloc{

[super dealloc];

}

-(NSString*)description{

NSMutableString* ns=[[NSMutableString alloc]init];

for(id item in todoarray){

[ns appendFormat:@"%@\n",item];

}

return ns;

}

@end

// TodoDb.h

// todolist

// Created by zz

#import <Foundation/Foundation.h>

@class Dolist;

@class Todo;

@interface TodoDb : NSObject <NSCoding>

{

NSString* filename;

Dolist* todolist;

}

@property(nonatomic,copy)NSString* filename;

@property(nonatomic,copy)Dolist* todolist;

-(id)initwithfilename:(NSString*)filename;

-(void)Addtodo:(Todo*)atodo;

-(void)Removetodo:(NSInteger)index;

-(Todo *)todoatindex:(NSInteger)index;

-(NSUInteger)TodoDBCount;

-(void)dealloc;

-(void)save;

-(void)read;

-(NSString*)description;

-(void)encodeWithCoder:(NSCoder *)aCoder;

-(id)initWithCoder:(NSCoder *)aDecoder;

@end

// TodoDb.m

// todolist

// Created by zz

#import "TodoDb.h"

#import "Todo.h"

#import "Dolist.h"

@implementation TodoDb

@synthesize filename;

@synthesize todolist;

-(id)initwithfilename:(NSString*)_filename{

if(!_filename){

[self release];

return nil;

}

self.filename=[NSString stringWithString:_filename];

todolist=[[Dolist alloc]init];

return self;

}

-(void)Addtodo:(Todo*)atodo{

[todolist Addtodo:atodo];

}

-(void)Removetodo:(NSInteger)index{

[todolist Removetodo:index];

}

-(Todo *)todoatindex:(NSInteger)index{

return [todolist todoatindex:index];

}

-(NSUInteger)TodoDBCount{

return [todolist Count];

}

-(void)dealloc{

[super dealloc];

}

-(void)save{

[NSKeyedArchiver archiveRootObject:[self description] toFile:filename];

}

-(void)read{

todolist= [NSKeyedUnarchiver unarchiveObjectWithFile:filename];

NSLog(@"%@",todolist);

}

-(NSString*)description{

NSString* ns=[[NSString alloc]initWithFormat:@"%@",todolist];

return ns;

}

-(void)encodeWithCoder:(NSCoder *)aCoder{

[aCoder encodeObject:todolist forKey:@"todolist"];

[aCoder encodeObject: filename forKey:@"filename"];

}

-(id)initWithCoder:(NSCoder *)aDecoder{

if((self=[super init])){

self.todolist=[aDecoder decodeObjectForKey:@"todolist"];

self.filename=[aDecoder decodeObjectForKey:@"filename"];

}

return self;

}

@end