ios数据存储方式FMDB

       从网上下载FMDB的原码,将其拖入到项目中，然后在Link Binary With Libraries中添加libsqlite3.dylib,就可以用了

  

  实现如下：

  

#import "ViewController.h"
#import "FMDatabase.h"
#import "FMDatabaseAdditions.h"
#import "FMDatabaseQueue.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.
}

- (void)dealloc {
    [_nameText release];
    [_ageText release];
    [_sexText release];
    [_showLabel release];
    [super dealloc];
}
- (void)viewDidUnload {
    [self setNameText:nil];
    [self setAgeText:nil];
    [self setSexText:nil];
    [self setShowLabel:nil];
    [super viewDidUnload];
}
//保存
- (IBAction)saveBtn:(id)sender {
    FMDatabase* database=[FMDatabase databaseWithPath:[self databasePath]];
    if (![database open]) {
        NSLog(@"Open database failed");
        return;
    }
    if (![database tableExists:@"user"]) {
        [database executeUpdate:@"create table user (id integer primary key autoincrement not null,name text,age integer,sex text)"];
    }
    BOOL insert=[database executeUpdate:@"insert into user (name,age,sex) values (?,?,?)",_nameText.text,[NSNumber numberWithInteger:[_ageText.text integerValue]],_sexText.text];
    //下面注释的也能实现数据的插入,只不过它是传入了字典
//    NSMutableDictionary* argsDict=[NSMutableDictionary dictionary];
//    [argsDict setObject:_nameText.text forKey:@"name"];
//    [argsDict setObject:_ageText.text forKey:@"age"];
//    [argsDict setObject:_sexText.text forKey:@"sex"];
//    BOOL insert=[database executeUpdate:@"insert into user (name,age,sex) values (:name,:age,:sex)" withParameterDictionary:argsDict];
    if (insert) {
        UIAlertView* alert=[[UIAlertView alloc] initWithTitle:@"提示" message:@"保存成功" delegate:nil cancelButtonTitle:nil otherButtonTitles:@"确定",nil];
        [alert show];
        [alert release];
    }else{
        NSLog(@"insert failed");
    }
    [database close];
    //下面注释的这一段也是创建表只不过它是多线程安全的，而上面的在多线程中是不安全的
//    FMDatabaseQueue* queue=[FMDatabaseQueue databaseQueueWithPath:[self databasePath]];
//    [queue inDatabase:^(FMDatabase* database){
//        if (![database tableExists:@"user"]) {
//            [database executeUpdate:@"create table user (id integer primary key autoincrement not null,name text,age integer,sex text)"];
//        }
//        BOOL insert=[database executeUpdate:@"insert into user (name,age,sex) values (?,?,?)",_nameText.text,[NSNumber numberWithInteger:[_ageText.text integerValue]],_sexText.text];
//        if (insert) {
//            UIAlertView* alert=[[UIAlertView alloc] initWithTitle:@"提示" message:@"保存成功" delegate:nil cancelButtonTitle:nil otherButtonTitles:@"确定",nil];
//            [alert show];
//            [alert release];
//        }else{
//            NSLog(@"insert failed");
//        }
//
//    }];
//    [queue close];
    
    
    
}
//显示所有数据库中的数据
- (IBAction)showBtn:(id)sender {
    FMDatabase* database=[FMDatabase databaseWithPath:[self databasePath]];
    if (![database open]) {
        return;
    }
    //注意 此处的FMResultSet可以不用关闭，因为数据库关闭的时候FMResultSet自动关闭
    FMResultSet* resultSet=[database executeQuery:@"select* from user"];
    NSString* str=@"";
    while ([resultSet next]) {
        NSString* name=[resultSet stringForColumn:@"name"];
        NSInteger age=[resultSet intForColumn:@"age"];
        NSString* sex=[resultSet stringForColumn:@"sex"];
        str=[str stringByAppendingFormat:@"Name:%@,Age:%d,Sex:%@\n",name,age,sex];
        NSLog(@"Name:%@,Age:%d,Sex:%@\n",name,age,sex);
    }
    _showLabel.text=str;
    [database close];
}
//查询
- (IBAction)checkBtn:(id)sender {
    FMDatabase* database=[FMDatabase databaseWithPath:[self databasePath]];
    if (![database open]) {
        return;
    }
    FMResultSet* resultSet=[database executeQuery:@"select* from user where name = ?",@"chen"];
    NSString* str=@"";
    while ([resultSet next]) {
        NSString* name=[resultSet stringForColumn:@"name"];
        NSInteger age=[resultSet intForColumn:@"age"];
        NSString* sex=[resultSet stringForColumn:@"sex"];
        str=[str stringByAppendingFormat:@"Name:%@,Age:%d,Sex:%@\n",name,age,sex];
    }
    _showLabel.text=str;
    [database close];
}
//删除
- (IBAction)deleteBtn:(id)sender {
    FMDatabase* database=[FMDatabase databaseWithPath:[self databasePath]];
    if (![database open]) {
        return;
    }
    BOOL delete=[database executeUpdate:@"delete from user where name = ?",@"chen"];
    if (delete) {
        UIAlertView* alert=[[UIAlertView alloc] initWithTitle:@"提示" message:@"删除成功" delegate:nil cancelButtonTitle:nil otherButtonTitles:@"确定",nil];
        [alert show];
        [alert release];
    }
    [database close];
}
//更新
- (IBAction)updateBtn:(id)sender {
    FMDatabase* database=[FMDatabase databaseWithPath:[self databasePath]];
    if (![database open]) {
        return;
    }
    BOOL update=[database executeUpdate:@"update user set age = ? where name= ?",[NSNumber numberWithInt:20],@"chen"];
    if (update) {
        UIAlertView* alert=[[UIAlertView alloc] initWithTitle:@"提示" message:@"更新成功" delegate:nil cancelButtonTitle:nil otherButtonTitles:@"确定",nil];
        [alert show];
        [alert release];
    }
    [database close];
}

-(NSString* )databasePath
{
    NSString* path=[NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0];
    NSString* dbPath=[path stringByAppendingPathComponent:@"user.db"];
    return dbPath;
    
}
@end