開源類庫之二 （FMDataBase）

FMDataBase是iOS平臺中一個非常強大的數據庫類庫，其將sqlite面向過程的接口以面向對象的方法展現出來，提供了極高的可用性。

其使用很簡單，將sqlite 庫添加到項目中，然後將FMDataBase類庫文件添加到項目中，下面是對筆者對FMDataBase進行的一個二次封裝，處理的數據庫很簡單，只有一張表，兩個列，存儲的都是一些key-value對，讀者可以根據自身需要對此類進行修改。

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

@interface DBController : NSObject {
}

@property (nonatomic, assign) FMDatabase *dataBase;

+(BOOL)databaseExit;

-(BOOL)initDatabase;

-(void)closeDatabase;

-(BOOL)deleteTable;

-(BOOL)InsertTable:(NSString *)key_type value:(NSString *)key_value;

-(BOOL)UpdataTable:(NSString *) valueStr key:(NSString *)keyStr;

-(NSMutableDictionary *)querryTable;

+(BOOL) deleteDataBase;

@end

@synthesize dataBase = _dataBase;

- (id)init{

    if(self = [super init]){
        _dataBase = [FMDatabase databaseWithPath: [DBController getPath]];
        if (![_dataBase open]) {
            NSLog(@"Create/Open dataBase %@ Failed!", [DBController getPath]);
        }
    }
    return self;
}

//數據庫是否存在
+(BOOL)databaseExit
{
    return [[NSFileManager defaultManager] fileExistsAtPath: [self getPath]];
}


//初始化數據庫
-(BOOL)initDatabase{
    if ([DBController databaseExit]) {
        return [self createTable];
    }
    return NO;
}



//創建數據庫
-(BOOL)createTable
{
    return [self.dataBase executeUpdate: @"create table if not exists personTable(id integer primary key autoincrement, key text,value text);"];
}

//刪除數據表
-(BOOL)deleteTable{
    if ([DBController databaseExit]) {
        return [self.dataBase executeUpdate: [NSString stringWithFormat:@"drop table %@;",_PERSONINFO]];
    }
    return NO;
}



//關閉數據庫
- (void) closeDatabase
{
    [self.dataBase close];
}

//插入數據
-(BOOL)InsertTable:(NSString *)key value:(NSString *)value
{
    if ([DBController databaseExit]) {
        BOOL result = NO;
        [self.dataBase beginTransaction];
        result = [self.dataBase executeUpdate:@"INSERT INTO personTable (key,value) VALUES (?,?)", key, value];
        [self.dataBase commit];
        return result;
    }
    return NO;
}

//更新數據
-(BOOL)UpdataTable:(NSString *) valueStr key:(NSString *)keyStr
{
    if ([DBController databaseExit]) {
        BOOL result = NO;
        [self.dataBase beginTransaction];
        result = [self.dataBase executeUpdate:@"UPDATE personTable SET value=? WHERE key=?", valueStr, keyStr];
        [self.dataBase commit];
        return result;
    }
    return NO;
}

//查詢整個表
-(NSMutableDictionary *)querryTable
{
    NSMutableDictionary* resultDic = [[NSMutableDictionary alloc] init];

    FMResultSet *rs = [self.dataBase executeQuery:@"select * from personTable"];
    while ([rs next]) {
        [resultDic setObject: [rs stringForColumn: @"value"] forKey: [rs stringForColumn: @"key"]];
    }
    return [resultDic autorelease];
}

+(BOOL) deleteDataBase
{
    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);

    NSString *documentsDirectory = [paths objectAtIndex:0];

    NSString *path = [documentsDirectory stringByAppendingPathComponent:_DBNAME];//設置數據庫得路徑

    NSFileManager *fileManager = [NSFileManager defaultManager];

    BOOL find = [fileManager fileExistsAtPath:path];

    if (find) {

        [fileManager removeItemAtPath: path error: nil];

    }
    return find;
}


- (void)dealloc {
    [_dataBase close];
    _dataBase = nil;
    [super dealloc];
}

+ (NSString*) getPath {
    // 打開的數據庫
    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);

    NSString *documentsDirectory = [paths objectAtIndex:0];

    return [documentsDirectory stringByAppendingPathComponent:_DBNAME];//設置數據庫得路徑
}


@end