从C#到Objective-C，循序渐进学习苹果开发(7)--使用FMDB对Sqlite数据库进行操作

FMDatabase *db= [FMDatabase databaseWithPath:dbPath] ;  
if (![db open]) {  
NSLog(@"无法打开数据库");  
return ;  
}  

- (BOOL) deleteByCondition:(NSString *) condition {
    NSString *query = [NSString stringWithFormat:@"Delete FROM %@ Where %@ ", self.tableName, condition];
    BOOL result = [self.database executeUpdate:query];
    return result;
}

[db executeUpdate:@"INSERT INTO User (Name,Age) VALUES (?,?)",@"张三",[NSNumber numberWithInt:30]]  

- (BOOL) deleteById:(id) key
{
    NSDictionary *argsDict = [NSDictionary dictionaryWithObjectsAndKeys:key, @"id", nil];
    NSString *query = [NSString stringWithFormat:@"Delete FROM %@ Where %@ =:id", self.tableName, self.primaryKey];
    BOOL result = [self.database executeUpdate:query withParameterDictionary:argsDict];
    return result;
}

FMResultSet *rs=[db executeQuery:@"SELECT * FROM User"];
rs=[db executeQuery:@"SELECT * FROM User WHERE Age = ?",@"20"];
while ([rs next]){
NSLog(@"%@ %@",[rs stringForColumn:@"Name"],[rs stringForColumn:@"Age"]);
}

 NSString *sqlQuery = @"SELECT * FROM User";
    sqlite3_stmt * statement;
    
    if (sqlite3_prepare_v2(db, [sqlQuery UTF8String], -1, &statement, nil) == SQLITE_OK) {
        while (sqlite3_step(statement) == SQLITE_ROW) {
            char *name = (char*)sqlite3_column_text(statement, 1);
            NSString *nsNameStr = [[NSString alloc]initWithUTF8String:name];
            int age = sqlite3_column_int(statement, 2);
            char *address = (char*)sqlite3_column_text(statement, 3);
            NSString *nsAddressStr = [[NSString alloc]initWithUTF8String:address];
            
            NSLog(@"name:%@  age:%d  address:%@",nsNameStr,age, nsAddressStr);
        }
    }
    sqlite3_close(db);

//
//  BaseEntity.h
//  MyDatabaseProject
//
//  Created by 伍华聪 on 14-4-2.
//  Copyright (c) 2014年 伍华聪. All rights reserved.
//

#import <Foundation/Foundation.h>

@interface BaseEntity : NSObject

@end

//
//  UserInfo.h
//  MyDatabaseProject
//
//  Created by 伍华聪 on 14-3-30.
//  Copyright (c) 2014年 伍华聪. All rights reserved.
//

#import <Foundation/Foundation.h>
#import "BaseEntity.h"

@interface UserInfo : BaseEntity

@property(nonatomic, copy) NSString *ID;
@property(nonatomic, copy) NSString *name;
@property(nonatomic, copy) NSString *fullName;

@end

//
//  BaseDAL.h
//  MyDatabaseProject
//
//  Created by 伍华聪 on 14-3-30.
//  Copyright (c) 2014年 伍华聪. All rights reserved.
//

#import <Foundation/Foundation.h>
#import "FMDatabase.h"
#import "BaseEntity.h"

@interface BaseDAL : NSObject
{
    NSString *pathToDatabase;
}

#pragma 数据库相关属性

@property (nonatomic, strong) NSString *pathToDatabase;
@property (nonatomic, readonly) FMDatabase *database;  // 数据库操作对象
@property (nonatomic, strong) NSString *tableName;//表名称
@property (nonatomic, strong) NSString *primaryKey;//主键
@property (nonatomic, strong) NSString *sortField;//排序，默认为主键
@property (nonatomic, assign, getter=isDescending) BOOL descending;//是否降序查询


//将DataReader的属性值转化为实体类的属性值，返回实体类(子类必须重写）
-(id) rsToEntity:(FMResultSet *)rs;

//将实体对象的属性值转化为字典列表对应的键值(子类必须重写）
-(NSDictionary *) dictByEntity:(BaseEntity *) info;


#pragma 基础操作接口

//根据指定对象的ID,从数据库中删除指定对象
- (BOOL) deleteById:(id) key;

//根据指定条件,从数据库中删除指定对象
- (BOOL) deleteByCondition:(NSString *) condition;

//更新对象属性到数据库中
-(BOOL) update:(BaseEntity *) info byKey:(id) key;

//插入指定对象到数据库中
-(BOOL) insert:(BaseEntity *) info;

//插入指定对象到数据库中,并返回最后插入的ID
-(NSInteger) insert2:(BaseEntity *) info;

//查询数据库,检查是否存在指定ID的对象
- (BaseEntity *) findById:(id) key;

//根据条件查询数据库,如果存在返回第一个对象
-(BaseEntity *) findSingle:(NSString *) condition;


//根据条件查询数据库,如果存在返回第一个对象
-(BaseEntity *) findSingle:(NSString *) condition orderBy:(NSString *) orderBy;

//根据条件查询数据库,并返回对象集合
- (NSArray *) find:(NSString *) condition;

//根据条件查询数据库,并返回对象集合
- (NSArray *) find:(NSString *) condition orderBy:(NSString *) orderBy;

//获取表的全部数据
- (NSArray *) getAll;

//获取表的全部数据
- (NSArray *) getAll:(NSString *) orderBy;

//获取某字段数据字典列表
-(NSArray *) getFieldList:(NSString *) fieldName;

//获取表的所有记录数量
-(int) getRecordCount;

//根据条件，获取表查询的记录数量
-(int) getRecordCount:(NSString *) condition;

//根据条件，判断是否存在记录
-(BOOL) isExistRecord:(NSString *)condition;

//查询数据库,检查是否存在指定键值的对象
-(BOOL) isExist:(NSString *)fieldName value:(id) value;

//根据主键和字段名称，获取对应字段的内容
-(NSString *) getFieldValue:(NSString *)key fieldName:(NSString *)fieldName;

//执行SQL查询语句，返回查询结果的所有记录的第一个字段,用逗号分隔。
-(NSString *) sqlValueList:(NSString *)query;

#pragma 数据库初始化函数及关闭操作

//根据SQLite数据库地址初始化数据库
-(id) initWithPath:(NSString *)filePath;

//根据SQLite数据库名称初始化数据库
-(id) initWithFileName:(NSString *)fileName;

// 关闭连接
-(void) close;

@end

- (NSArray *) find:(NSString *) condition orderBy:(NSString *) orderBy {
    NSString *query = [NSString stringWithFormat:@"SELECT * FROM %@ ", self.tableName];
    if (condition != nil) {
        query = [query stringByAppendingFormat:@" where %@ ", condition];
    }
    
    if (orderBy != nil) {
        query = [query stringByAppendingString:orderBy];
    }
    else {
        query = [query stringByAppendingFormat:@" ORDER BY %@ %@ ", self.sortField, self.isDescending ? @"DESC" : @"ASC"];
    }
    
    FMResultSet *rs = [self.database executeQuery:query];
    NSMutableArray *array = [NSMutableArray arrayWithCapacity:[rs columnCount]];
    
    BaseEntity *info = nil; //默认初始化为空
    while ([rs next]) {
        info = [self rsToEntity:rs];
        [array addObject:info];
    }
    [rs close];
    
    return array;
}

info = [self rsToEntity:rs];

//
//  UserDAL.h
//  MyDatabaseProject
//
//  Created by 伍华聪 on 14-3-30.
//  Copyright (c) 2014年 伍华聪. All rights reserved.
//

#import <Foundation/Foundation.h>
#import "FMDatabase.h"
#import "BaseDAL.h"
#import "UserInfo.h"

@interface UserDAL : BaseDAL
{
}

//单例模式
+(UserDAL *) defaultDAL;

@end