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        C# 創(chuàng)建MDB數(shù)據(jù)庫、并存放表格數(shù)據(jù)的案例

         更新時間:2021年01月14日 10:43:17   作者:南方北先生  
        這篇文章主要介紹了C# 創(chuàng)建MDB數(shù)據(jù)庫、并存放表格數(shù)據(jù)的案例,具有很好的參考價值,希望對大家有所幫助。一起跟隨小編過來看看吧

        下面是近期學(xué)習(xí)C#連接MDB數(shù)據(jù)庫,通過路徑創(chuàng)建MDB數(shù)據(jù)庫,根據(jù)名字創(chuàng)建創(chuàng)建對用MDB數(shù)據(jù)庫中的表格,再通過DataTable創(chuàng)建一致的表并將數(shù)據(jù)放入,這是一個類,用完之后記得用Close()方法。

        添加引用:

        目的是//創(chuàng)建Catalog目錄類

        ADOX.CatalogClass catalog = new ADOX.CatalogClass();

        using System;
        using System.Collections.Generic;
        using System.Linq;
        using System.Text;
        using System.Data;
        using System.Data.OleDb;
        using System.Data.SqlClient;
        using System.IO;
        using System.Windows.Forms;
        namespace PartOfJRSpace.DataHelper
        {
         public class mdbHelper
         {
          private OleDbConnection myConn;
          protected string test1;
          /// <summary>
          /// 初始化連接數(shù)據(jù)庫
          /// </summary>
          /// <param name="address"></param>
          public mdbHelper(string address)
          {
           try
           {
            //創(chuàng)建一個 OleDbConnection對象
            string strCon = " Provider = Microsoft.Jet.OLEDB.4.0 ; Data Source =" + address;
            myConn = new OleDbConnection(strCon);
            myConn.Open();
           }
           catch (Exception ex)
           {
            ex.ToString();
           }
          }
          /// <summary>
          /// 關(guān)閉數(shù)據(jù)連接
          /// </summary>
          public void CloseConnection()
          {
           myConn.Close();
          }
          /// <summary>
          /// 創(chuàng)建一個類型和datatable一致的空表
          /// </summary>
          /// <param name="tableName"></param>
          public void CreateTable(string tableName,DataTable dt)
          {
           try
           {
            string sql = "create table " + tableName;
            string tableAttribute = "";
            //for (int i = 0; i < dt.Columns.Count; i++)
            //{
            // tableAttribute = tableAttribute + dt.Columns[i].ColumnName + " " + GetType(dt.Columns[i].DataType.ToString()) + ",";
            //}
            //sql = sql + "(Num AUTOINCREMENT," + tableAttribute + "CONSTRAINT table_PK PRIMARYKEY(Num));";
            for (int i=0;i<dt.Columns.Count;i++)
            {
             tableAttribute = tableAttribute + dt.Columns[i].ColumnName + " " + GetType(dt.Columns[i].DataType.ToString());
             if (i < dt.Columns.Count - 1)
             {
              tableAttribute = tableAttribute + ",";
             }
            }
            sql = sql + "(" + tableAttribute + ");";
            OleDbCommand cmd = new OleDbCommand(sql, myConn);
            cmd.ExecuteNonQuery();
           }
           catch(Exception ex)
           {
            throw;
           }
          }
          /// <summary>
          /// 將datatable導(dǎo)入對應(yīng)名字的表中
          /// </summary>
          /// <param name="path"></param>
          /// <param name="name"></param>
          /// <param name="dt"></param>
          public void DatatableToMdb(string name,DataTable dt)
          {
           try
           {
            
            string strCom = string.Format("select * from {0}", name);
            OleDbDataAdapter da = new OleDbDataAdapter(strCom, myConn);
            //****
            OleDbCommandBuilder cb = new OleDbCommandBuilder(da);//這里的CommandBuilder對象一定不要忘了,一般就是寫在DataAdapter定義的后面
            cb.QuotePrefix = "[";
            cb.QuoteSuffix = "]";
            DataSet midData = new DataSet();
            da.Fill(midData, name);
            foreach (DataRow dR in dt.Rows)
            {
             DataRow dr = midData.Tables[name].NewRow();
             dr.ItemArray = dR.ItemArray;//行復(fù)制
             midData.Tables[name].Rows.Add(dr);
            }
            da.Update(midData,name);
            
           }
           catch (Exception ex)
           {
            throw;
           }
          }
          /// <summary>
          /// 獲取創(chuàng)建mdb表格的屬性字段類型
          /// </summary>
          /// <param name="datatype"></param>
          /// <returns></returns>
          private string GetType(string datatype)
          {
           switch (datatype)//匹配類型選擇
           {
            case "System.String":
             return "TEXT(50)";
            case "System.DateTime":
             return "DateTime";
            case "System.Double":
             return "Double";
            case "System.Int32":
            case "System.Int16":
            case "System.Int64":
             return "Int";
            default:
             return "TEXT(50)";  
           }
          }
          /// <summary>
          /// 創(chuàng)建Access數(shù)據(jù)庫
          /// </summary>
          /// <param name="path">文件和文件路徑</param>
          /// <returns>真為創(chuàng)建成功,假為創(chuàng)建失敗或是文件已存在</returns>
          public static bool CreateAccessDatabase(string path)
          {
           //如果文件存在反回假
           if (File.Exists(path))
           {
            MessageBox.Show("文件已存在!");
            return false;
           }
           try
           {
            //如果目錄不存在,則創(chuàng)建目錄
            string dirName = Path.GetDirectoryName(path);
            if (!Directory.Exists(dirName))
            {
             Directory.CreateDirectory(dirName);
            }
            //創(chuàng)建Catalog目錄類
            ADOX.CatalogClass catalog = new ADOX.CatalogClass();
            string _connectionStr = "Provider=Microsoft.Jet.OLEDB.4.0;" + "Data Source=" + path
                   + ";";
            //根據(jù)聯(lián)結(jié)字符串使用Jet數(shù)據(jù)庫引擎創(chuàng)建數(shù)據(jù)庫
            catalog.Create(_connectionStr);
            catalog = null;
            return true;
           }
           catch (Exception)
           {
            throw new Exception("數(shù)據(jù)庫創(chuàng)建失敗!");
           }
          }
         }
         
        }
        

        補(bǔ)充:c#操作Access,對MDB數(shù)據(jù)的table進(jìn)行操作,包括新增,讀取

        文介紹C#訪問操作Access數(shù)據(jù)庫的基礎(chǔ)知識,并提供一個相關(guān)的例程。C#的ADO.NET還不能通過編程方式創(chuàng)建全新的ACCESS(MDB)數(shù)據(jù)庫,所以還只能使用ADOX這個來自COM的鏈接庫來操作。

        主要知識點(diǎn)如下:

        using System.Data.OleDb;
        using System.Data;

        連接字符串:

        String connectionString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=product.mdb";

        建立連接:

        OleDbConnection connection = new OleDbConnection(connectionString);

        使用OleDbCommand類來執(zhí)行Sql語句:

        OleDbCommand cmd = new OleDbCommand(sql, connection);
        connection.Open();
        cmd.ExecuteNonQuery();

        1.創(chuàng)建mdb庫,例程如下:

        需要注意的是:參數(shù)mdbPath是mdb的完整路徑(不包含表的名稱)。例如:D://test.mdb

        //創(chuàng)建mdb 
          public static bool CreateMDBDataBase(string mdbPath)
          {
           try
           {
            ADOX.CatalogClass cat = new ADOX.CatalogClass();
            cat.Create("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + mdbPath + ";");
            cat = null;
            return true;
           }
           catch { return false; }
          }

        2.創(chuàng)建具體的表,例程如下:

        通常一個mdb的可以包含n個表。下面的程序主要是創(chuàng)建一個table。

        //新建mdb的表 
          //mdbHead是一個ArrayList,存儲的是table表中的具體列名。 
          public static bool CreateMDBTable(string mdbPath,string tableName, ArrayList mdbHead)
          {
           try
           {
            ADOX.CatalogClass cat = new ADOX.CatalogClass();
            string sAccessConnection
             = @"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + mdbPath;
            ADODB.Connection cn = new ADODB.Connection();
            cn.Open(sAccessConnection, null, null, -1);
            cat.ActiveConnection = cn;
         
            //新建一個表 
            ADOX.TableClass tbl = new ADOX.TableClass();
            tbl.ParentCatalog = cat;
            tbl.Name = tableName;
         
            int size = mdbHead.Count;
            for (int i = 0; i < size; i++)
            {
             //增加一個文本字段 
             ADOX.ColumnClass col2 = new ADOX.ColumnClass();
             col2.ParentCatalog = cat;
             col2.Name = mdbHead[i].ToString();//列的名稱 
             col2.Properties["Jet OLEDB:Allow Zero Length"].Value = false;
             tbl.Columns.Append(col2, ADOX.DataTypeEnum.adVarWChar, 500);
            }
            cat.Tables.Append(tbl); //這句把表加入數(shù)據(jù)庫(非常重要) 
            tbl = null;
            cat = null;
            cn.Close();
            return true;
           }
           catch { return false; }
          }

        3.讀取mdb內(nèi)容(完全讀取),例程如下:

        本例程返回的是一個DataTable,如需其他格式可以自行轉(zhuǎn)換。

        // 讀取mdb數(shù)據(jù) 
          public static DataTable ReadAllData(string tableName, string mdbPath,ref bool success)
          {
           DataTable dt = new DataTable();
           try
           {
            DataRow dr;
            //1、建立連接 
            string strConn
             = @"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + mdbPath + ";Jet OLEDB:Database Password=haoren";
            OleDbConnection odcConnection = new OleDbConnection(strConn);
            //2、打開連接 
            odcConnection.Open();
            //建立SQL查詢 
            OleDbCommand odCommand = odcConnection.CreateCommand();
            //3、輸入查詢語句 
            odCommand.CommandText = "select * from " + tableName;
            //建立讀取 
            OleDbDataReader odrReader = odCommand.ExecuteReader();
            //查詢并顯示數(shù)據(jù) 
            int size = odrReader.FieldCount;
            for (int i = 0; i < size; i++)
            {
             DataColumn dc;
             dc = new DataColumn(odrReader.GetName(i));
             dt.Columns.Add(dc);
            }
            while (odrReader.Read())
            {
             dr = dt.NewRow();
             for (int i = 0; i < size; i++)
             {
              dr[odrReader.GetName(i)] = odrReader[odrReader.GetName(i)].ToString();
             }
             dt.Rows.Add(dr);
            }
            //關(guān)閉連接 
            odrReader.Close();
            odcConnection.Close();
            success = true;
            return dt;
           }
           catch
           {
            success = false;
            return dt;
           }
          }

        4.讀取mdb內(nèi)容(按列讀?。倘缦拢?/h3>

        columns數(shù)組存儲的是你要查詢的列名稱(必須確保mdb表中存在你要的列)

        // 讀取mdb數(shù)據(jù) 
          public static DataTable ReadDataByColumns(string mdbPaht,string tableName, string[] columns, ref bool success)
          {
           DataTable dt = new DataTable();
           try
           {
            DataRow dr;
            //1、建立連接 
            string strConn
             = @"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + mdbPath + ";Jet OLEDB:Database Password=haoren";
            OleDbConnection odcConnection = new OleDbConnection(strConn);
            //2、打開連接 
            odcConnection.Open();
            //建立SQL查詢 
            OleDbCommand odCommand = odcConnection.CreateCommand();
            //3、輸入查詢語句 
            string strColumn = "";
            for (int i = 0; i < columns.Length; i++)
            {
             strColumn += columns[i].ToString() + ",";
            }
            strColumn = strColumn.TrimEnd(',');
            odCommand.CommandText = "select "+strColumn+" from " + tableName;
            //建立讀取 
            OleDbDataReader odrReader = odCommand.ExecuteReader();
            //查詢并顯示數(shù)據(jù) 
            int size = odrReader.FieldCount;
            for (int i = 0; i < size; i++)
            {
             DataColumn dc;
             dc = new DataColumn(odrReader.GetName(i));
             dt.Columns.Add(dc);
            }
         
            while (odrReader.Read())
            {
             dr = dt.NewRow();
             for (int i = 0; i < size; i++)
             {
              dr[odrReader.GetName(i)] = odrReader[odrReader.GetName(i)].ToString();
             }
             dt.Rows.Add(dr);
            }
            //關(guān)閉連接 
            odrReader.Close();
            odcConnection.Close();
            success = true;
            return dt;
           }
           catch
           {
            success = false;
            return dt;
           }
          }

        以上為個人經(jīng)驗(yàn),希望能給大家一個參考,也希望大家多多支持腳本之家。如有錯誤或未考慮完全的地方,望不吝賜教。

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