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  • OC中数据库操作(类方法)

    1.创建表格

    +(sqlite3 *)getMySQL{

        sqlite3 *mySQL;

        //打开数据库,如果没有就创建

      //拼接路径

            NSString *docPath = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) lastObject];

            NSString *filePath = [docPath stringByAppendingPathComponent:@"Worker.SQL"];

            NSLog(@"%@",filePath);

            //调用open方法

            if (sqlite3_open([filePath UTF8String], &mySQL) != SQLITE_OK) {

                NSLog(@"open error");

                return 0;

            }

            NSLog(@"open OK");

            //3.创建表的sql语句

            NSString *createTableSql = @"create table if not exists Workers (id integer primary key autoincrement,name varchar(30),address varchar(40),image blob)";

            char *errMsg = NULL;

      //写入数据库

            if (sqlite3_exec(mySQL, [createTableSql UTF8String], NULL, NULL, &errMsg)) {

                NSLog(@"%s",errMsg);

                return 0;

            }

            NSLog(@"create table ok");

        return mySQL;

    }

     2.表格里插入语句

    +(void)insertSqlWithName:(NSString *)name Address:(NSString *)address Image:(UIImage *)image{

        sqlite3 *database = [SQLFactory getMySQL];

        NSString *insertSql = @"insert into Workers(name,address,image) values(?,?,?)";

        sqlite3_stmt *statement;

        if (sqlite3_prepare_v2(database, [insertSql UTF8String], -1, &statement, NULL) != SQLITE_OK) {

            NSLog(@"insert prepare error");

            return;

        }else{

            NSLog(@"insert prepare OK");

            NSData *imgData = UIImagePNGRepresentation(image);

            sqlite3_bind_text(statement, 1, [name UTF8String], -1, NULL);

            sqlite3_bind_text(statement, 2, [address UTF8String], -1, NULL);

            sqlite3_bind_blob(statement, 3, [imgData bytes], (int)imgData.length, NULL);

            if (sqlite3_step(statement) != SQLITE_DONE) {

                NSLog(@"执行插入语句失败");

            }else{

                NSLog(@"执行插入语句成功");

            }

        }

    }

     3,读取数据

    +(NSMutableArray *)showSqlWithSeletType:(NSString *)selectType{

        NSMutableArray *workerModelsArray = [NSMutableArray array];

        sqlite3 *sql = [SQLFactory getMySQL];

        sqlite3_stmt *statement;

        if (sqlite3_prepare_v2(sql, [selectType UTF8String], -1, &statement, NULL) != SQLITE_OK) {

            NSLog(@"read prepare error");

            return 0;

        }else{

            NSLog(@"read prepare OK");

            while (sqlite3_step(statement) == SQLITE_ROW) {

                WorkerModel *model = [[WorkerModel alloc]init];

                char *name = (char *)sqlite3_column_text(statement, 1);

                model.workerName = [NSString stringWithUTF8String:name];

                

                char *address = (char *)sqlite3_column_text(statement, 2);

                model.workerAddress = [NSString stringWithUTF8String:address];

                

                Byte *bytes = (Byte *)sqlite3_column_blob(statement, 3);

                int length = sqlite3_column_bytes(statement, 3);

                

                NSData *imgData = [NSData dataWithBytes:bytes length:length];

                UIImage *img = [UIImage imageWithData:imgData];

                model.workerIconImage = img;

                [workerModelsArray addObject:model];

            }

        }

        return workerModelsArray;

    }

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  • 原文地址:https://www.cnblogs.com/yangqinglong/p/5367136.html
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