[SQLite]---database
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注意： 1.使用该方法时注意要给项目中添加database.h和database.m文件以及PlausibleDatabase.framework框架。 2.在框架中导入libsqlite3.dylib框架。 3.把你的sqlite文件添加到项目中
4.在database.m文件中修改以下内容。 5.正式开始-------------------------------------------------------------------------------- 启动数据库并进行查询操作 -(void)refreshArray{ PLSqliteDatabase *db = [DataBasesetup]; NSString *sql = [NSStringstringWithFormat:@"select * from %@",attribute]; id<PLResultSet>rs = [dbexecuteQuery:sql]; while ([rsnext]) { NSMutableDictionary *myDict = [[NSMutableDictionaryalloc]init]; NSString *list = [rsstringForColumn:@"list"]; [myDict setObject:listforKey:@"list"]; // NSLog(@"list ---- %@",list); NSString *words = [rsstringForColumn:@"words"]; [myDict setObject:wordsforKey:@"words"]; // NSLog(@"words ---- %@",words); NSData *picData = [rsdataForColumn:@"picture"]; // NSLog(@"picData ---- %@",picData); [myDict setObject:picDataforKey:@"picture"]; [myArrayaddObject:myDict]; [myDict release]; } }
向sqlite数据库插入和读取二进制图片数据 (for ios) 假定数据库中存在表 test_table(name,image),下面代码将图片文件test.png的二进制数据写到sqlite数据库： UIImage *image = [UIImageimageNamed:@"tree.png"]; NSData *data = UIImagePNGRepresentation(image); NSString *sql = [NSStringstringWithFormat:@"insert into test_tablevalues('%@')",data]; PLSqliteDatabase *db = [DataBasesetup]; [db executeUpdate:sql];
下面代码从数据库中读取图片二进制数据，然后转换成图片image格式： NSString *sql =@"select picture from test_table where mnumber=1"; PLSqliteDatabase *db = [DataBasesetup]; id<PLResultSet>rs = [dbexecuteQuery:sql]; while ([rsnext]) { NSData *data = [rsdataForColumn:@"picture"]; UIImage *image = [UIImageimageWithData:data];//此即为读出的图片，然后按你自己的需求使用即可 }
下面代码将图片文件test.png的二进制数据写到sqlite数据库： char *name = "test"; NSString * nameString = [NSString stringWithCString:name encoding:NSUTF8StringEncoding]; NSString * filePath = [[NSBundle mainBundle] pathForResource:nameString ofType:@"png"]; if ([[NSFileManager defaultManager] fileExistsAtPath:filePath]) { NSData * imgData = UIImagePNGRepresentation([UIImage imageWithContentsOfFile:filePath]); const char * sequel = "insert into test_table(name,image) values(?,?)"; sqlite3_stmt * update; if (sqlite3_prepare_v2(database,sequel,-1,&update,NULL) == SQLITE_OK) { sqlite3_bind_text(update,1,name,NULL); sqlite3_bind_blob(update,2,[imgData bytes],[imgData length],NULL); if( sqlite3_step(update) == SQLITE_DONE) { NSLog(@"已经写入数据"); } sqlite3_finalize(update); } } else { System Italic 27.0 NSLog(@"文件不存在"); } 下面代码从数据库中读取图片二进制数据，然后显示图片： const char * sequel = "select image from test_table where name=?"; sqlite3_stmt * getimg; if (sqlite3_prepare_v2(database,&getimg,NULL) == SQLITE_OK) { char *name = "test"; sqlite3_bind_text(update,NULL); if(sqlite3_step(getimg) == SQLITE_ROW) { int bytes = sqlite3_column_bytes(getimg,0); Byte * value = (Byte*)sqlite3_column_blob(getimg,1); if (bytes !=0 && value != NULL) { NSData * data = [NSData dataWithBytes:value length:bytes]; UIImage * img = [UIImage imageWithData:data]; UIImageView * aview =[[UIImageView alloc] initWithFrame:CGRectMake(0.0,0.0,IMAGE_WIDTH,IMAGE_HEIGHT)]; aview.image = img; [self.view addSubview:aview]; [aview release]; } } sqlite3_finalize(getimg); } （编辑：李大同） 【声明】本站内容均来自网络，其相关言论仅代表作者个人观点，不代表本站立场。若无意侵犯到您的权利，请及时与联系站长删除相关内容! |