IOS开发－本地持久化存储sqlite应用

1. 前言
2. 需求描述
3. 开发测试环境
4. FMDB介绍
5. 创建工程

一、前言

上一章介绍了如何开发一个IOS应用的入门案例教程：

                    我的第一个IOS开发应用 

　　本章主要将介绍如何使用sqlite，来进行本地持久化存储数据。

二、需求描述

在游戏开始一段时间后，我们需要存储角色的基础信息，以便我休息之后继续进行上次的旅途。

三、开发环境介绍

OS X EI Captian：10.11.4

Xcode： 7.3

ios：9.3

机型：iphone 6s／iphone 6s plus

四、FMDB介绍

iOS中的数据持久化方式，基本上有以下四种：

1. 属性列表
2. 对象归档
3. SQLite3
4. Core Data

本文主要介绍如何使用“SQLite3” 持久化方式。

SQLite：是一个开源的嵌入式关系数据库，它在2000年由D. Richard Hipp发布，它的减少应用程序管理数据的开销，
        SQLite可移植性好，很容易使用，很小，高效而且可靠。
        参考地址：http://www.sqlite.org/

FMDB：iOS、macOS开源的第三方库对SQLite的操作进行了封装。
      参考地址：https://github.com/ccgus/fmdb.git

五、创建工程

Xcode 英文版：

1.“Create a new Xcode project”

2.“Choose a template for your new project”>  iOS > Application > Single View Application

3. “Choose options for your new project”

Bundle Identifier：cn.oshine.ios.Lesson02，

Language : Objective-C ,

Devices: iPhone ,

Use Core Data: No,

include Unit Tests:  No,

include UI Tests: No

4. "Select Folder To Create"

下载FMDB，FMDB的目录结构

把fmdb.xcodeproj拖动到工作区中。

Lesson02 TARGETS  ：

Build Pharses:

Target Dependencies > FMDB iOS(fmdb)

Link Binary With Libraries > libsqlite3.0.tbd

Link Binary With Libraries > libFMDB-iOS.a

引入头文件：

#import <Foundation/Foundation.h>

#import "fmdb/FMDB.h"

#import <sqlite3.h>

创建数据库：

FMDatabase *db = [FMDatabase databaseWithPath:@"/tmp/tmp.db"];

if (![db open]) {

         NSLog(@"OPEN FAIL");

        return;

}

关闭数据库：

[db close];

创建表：

 [db executeUpdate:@"CREATE TABLE IF NOT EXISTS profile(name text,val text)"];

插入记录：

  [db beginTransaction];

    [db executeUpdate:@"INSERT INTO profile(name,val) VALUES (?,?)",@"HP",@""];

    [db executeUpdate:@"INSERT INTO profile(name,val) VALUES (?,?)",@"MP",@""];

    [db executeUpdate:@"INSERT INTO profile(name,val) VALUES (?,?)",@"攻击",@""];

    [db executeUpdate:@"INSERT INTO profile(name,val) VALUES (?,?)",@"防御",@""];

    [db executeUpdate:@"INSERT INTO profile(name,val) VALUES (?,?)",@"攻速",@"0.3"];

    [db executeUpdate:@"INSERT INTO profile(name,val) VALUES (?,?)",@"移速",@""];

    [db commit];

读取记录：

 FMDatabase *db = [FMDatabase databaseWithPath:@"/tmp/tmp.db"];

    if (![db open]) {

        NSLog(@"OPEN FAIL");

        return;

    }

    NSMutableDictionary *dictionary = [NSMutableDictionary dictionary];

    FMResultSet *rs = [db executeQuery:@"SELECT name,val FROM profile"];

    while ([rs next]) {

        [dictionary setObject:[rs stringForColumn:@"val"] forKey:[rs stringForColumn:@"name"]];

    }

    [rs close];

    [db close];

案例界面：

案例代码：

运行结果：

ViewController.h

//
//  ViewController.h
//  Lesson02
//
//  Created by ouyangjunqiu on 16/4/7.
//  Copyright © 2016年 oshine. All rights reserved.
//

#import <UIKit/UIKit.h>
#import <Foundation/Foundation.h>
#import "fmdb/FMDB.h"
#import <sqlite3.h>

@interface ViewController : UIViewController

@property (weak, nonatomic) IBOutlet UILabel *label;

- (IBAction)createTable:(id)sender;

- (IBAction)initRole:(id)sender;

- (IBAction)readProfile:(id)sender;

@end

ViewController.m

//
//  ViewController.m
//  Lesson02
//
//  Created by ouyangjunqiu on 16/4/7.
//  Copyright © 2016年 oshine. All rights reserved.
//

#import "ViewController.h"

@interface ViewController ()

@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
}

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

- (IBAction)createTable:(id)sender {
    FMDatabase *db = [FMDatabase databaseWithPath:@"/tmp/tmp.db"];

    if (![db open]) {
         NSLog(@"OPEN FAIL");
        return;
    }

    [db executeUpdate:@"CREATE TABLE IF NOT EXISTS profile(name text,val text)"];
    [db close];
}

- (IBAction)initRole:(id)sender {
    FMDatabase *db = [FMDatabase databaseWithPath:@"/tmp/tmp.db"];

    if (![db open]) {
        NSLog(@"OPEN FAIL");
        return;
    }

    [db beginTransaction];
    [db executeUpdate:@"INSERT INTO profile(name,val) VALUES (?,?)",@"HP",@""];
    [db executeUpdate:@"INSERT INTO profile(name,val) VALUES (?,?)",@"MP",@""];
    [db executeUpdate:@"INSERT INTO profile(name,val) VALUES (?,?)",@"攻击",@""];
    [db executeUpdate:@"INSERT INTO profile(name,val) VALUES (?,?)",@"防御",@""];
    [db executeUpdate:@"INSERT INTO profile(name,val) VALUES (?,?)",@"攻速",@"0.3"];
    [db executeUpdate:@"INSERT INTO profile(name,val) VALUES (?,?)",@"移速",@""];
    [db commit];
    [db close];

}

- (IBAction)readProfile:(id)sender{
    FMDatabase *db = [FMDatabase databaseWithPath:@"/tmp/tmp.db"];

    if (![db open]) {
        NSLog(@"OPEN FAIL");
        return;
    }
    NSMutableDictionary *dictionary = [NSMutableDictionary dictionary];
    FMResultSet *rs = [db executeQuery:@"SELECT name,val FROM profile"];
    while ([rs next]) {
        [dictionary setObject:[rs stringForColumn:@"val"] forKey:[rs stringForColumn:@"name"]];
    }
    [rs close];
    [db close];

    [self show:dictionary];
}

-(void)show:(NSMutableDictionary *)dictionary {

    self.label.numberOfLines = ;

    NSString * text = [[NSString alloc] init];
    for(NSString *key in dictionary) {
        text = [NSString stringWithFormat:@"%@%@:%@\n",text,key,[dictionary objectForKey:key]];
    }
    self.label.text = text;
}

@end

案例结束

NSMutableDictionary Class Reference （key->value可增长数组）

https://developer.apple.com/library/ios/documentation/Cocoa/Reference/Foundation/Classes/NSMutableDictionary_Class/