Access

using System;
using System.Data.OleDb;
using System.Data;
using System.Windows.Forms;
using System.IO;
using ADODB;
using ADOX;


namespace DB
{
    
    
    class AccessDBUtil
    {
    
    
        private static string fileName = "";

        static string str_url = "";
        private static String connectionString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + str_url;

        private AccessDBUtil()
        {
    
    

        }
        //判断数据库是否存在，如果不存在则创建数据库
        public static void checkDBExists()
        {
    
    
            if (!File.Exists(str_url))
            {
    
    

                Catalog catalog = new Catalog();
                try
                {
    
    
                    catalog.Create(connectionString);

                    //连接数据库
                    ADODB.Connection cn = new ADODB.Connection();
                    cn.Open(connectionString, null, null, -1);
                    catalog.ActiveConnection = cn;
                    CreateParaOpDB(catalog,"tableName");
             
                    catalog = null;
                    cn.Close();
                }
                catch(Exception ex)
                {
    
    

                    WriteLogToFile.WriteLog(ex);
                }
            }
        }

        
 
  
        private static void CreateParaOpDB(Catalog catalog,string tableName)
        {
    
    

            Table table = new Table();
            table.Name = tableName;

            Column column = new Column();
            column.ParentCatalog = catalog;
            column.Type = ADOX.DataTypeEnum.adInteger; // 必须先设置字段类型
            column.Name = "ID";
            column.DefinedSize = 8;
            column.Properties["AutoIncrement"].Value = true;
            table.Columns.Append(column, ADOX.DataTypeEnum.adInteger, 0);
          
            table.Columns.Append("Num", ADOX.DataTypeEnum.adVarWChar, 120);
            table.Columns.Append("DateTime", ADOX.DataTypeEnum.adVarWChar, 120);
    


            try
            {
    
    
                catalog.Tables.Append(table);
            }
            catch (Exception ex)
            {
    
    
                Console.WriteLine(ex);
           
            }
            //此处一定要关闭连接，否则添加数据时候会出错
            table = null;
            Application.DoEvents();
        }

      
        public static DataSet ExecuteQuery(string sql)
        {
    
    
            return ExecuteQuery(sql, null);
        }
        //执行查询语句，返回dataset
        public static DataSet ExecuteQuery(string sql, OleDbParameter[] parameters)
        {
    
    
            //Debug.WriteLine(sql);
            using (OleDbConnection connection = new OleDbConnection(connectionString))
            {
    
    
                DataSet ds = new DataSet();
                try
                {
    
    
                    connection.Open();

                    OleDbDataAdapter da = new OleDbDataAdapter(sql, connection);
                    if (parameters != null) da.SelectCommand.Parameters.AddRange(parameters);
                    da.Fill(ds, "ds");
                }
                catch (Exception ex)
                {
    
    
                      Console.WriteLine(ex);
                }
                return ds;
            }
        }
        public static int ExecuteInsert(string sql)
        {
    
    
            return ExecuteInsert(sql, null);
        }
        //执行单条插入语句，并返回id，不需要返回id的用ExceuteNonQuery执行。
        public static int ExecuteInsert(string sql, OleDbParameter[] parameters)
        {
    
    
            Console.WriteLine(sql);

            using (OleDbConnection connection = new OleDbConnection(connectionString))
            {
    
    
                OleDbCommand cmd = new OleDbCommand(sql, connection);
                try
                {
    
    
                    connection.Open();
                    if (parameters != null) cmd.Parameters.AddRange(parameters);
                    cmd.ExecuteNonQuery();
                    cmd.CommandText = @"select @@identity";
                    int value = Int32.Parse(cmd.ExecuteScalar().ToString());
                    return value;
                }
                catch (Exception e)
                {
    
    
                          Console.WriteLine(ex);
                    throw e;
                }
            }
        }

    }
}