C# 创建Access数据库及数据表的增删改查

Posted 2020-09-06 ShawSir

 

//动态库引用
//Microsoft ActiveX Data Objects 6.0 Libraryy
//Microsoft ADO Ext. 6.0 for DDL and Securty
//可以在动态库管理器的COM中找到,但实际上就是ADODB.DLL和ADOX.DLL

using System.Data.OleDb;
using ADOX;

 

  1     class ADOXer
  2     {
  3         /// <summary>
  4         /// 激活Access数据库(创建或打开)
  5         /// </summary>
  6         /// <param name="dbName">数据库全路径</param>
  7         /// <param name="pwd">密码</param>
  8         /// <returns>数据库</returns>
  9         private static Catalog ActivateDB(string dbName, string pwd, out string msg)
 10         {
 11             msg = "";
 12             Catalog catalog = null;
 13 
 14             string conn = "";
 15             if (string.IsNullOrEmpty(pwd))
 16                 conn = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + dbName;
 17             else
 18                 conn = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + dbName + ";Jet OLEDB:Database Password=" + pwd + ";Jet OLEDB:Engine Type=5";
 19 
 20             try
 21             {
 22                 catalog = new Catalog();
 23                 if (File.Exists(dbName))
 24                 {
 25                     catalog.let_ActiveConnection(conn); /*绑定连接,获取对象*/
 26                 }
 27                 else
 28                     catalog.Create(conn); /*绑定连接,创建对象*/
 29             }
 30             catch (Exception ex)
 31             { msg = "数据库激活失败:" + ex.Message; }
 32 
 33             return catalog;
 34         }
 35         /// <summary>
 36         /// 创建Access数据表
 37         /// </summary>
 38         /// <param name="dbName">数据库实例名(即数据库文件)</param>
 39         /// <param name="pwd">数据库密码</param>
 40         /// <param name="tbName">数据表名</param>
 41         /// <param name="columnNames">数据表列名序列</param>
 42         /// <returns></returns>
 43         public static string CreateTB(string dbName, string pwd, string tbName, params string[] columnNames)
 44         {
 45             string msg = "";
 46             if (columnNames.Length <= 1) return "数据列不足";
 47             Catalog catalog = ActivateDB(dbName, pwd, out msg);
 48             if (!string.IsNullOrEmpty(msg)) return msg;
 49 
 50             if (catalog.Tables.Count>0)
 51                 foreach (ADOX.Table t in catalog.Tables)
 52                 {
 53                     if (t.Name.Equals(tbName))
 54                         return "数据表已存在";
 55                 }
 56              
 57             ADODB.Connection cnn = new ADODB.Connection();
 58             cnn=catalog.ActiveConnection;
 59 
 60             ADOX.Table tb = new ADOX.Table();
 61             tb.Name = tbName;
 62             //主键列
 63             ADOX.Column keyCol = new ADOX.Column();
 64             keyCol.ParentCatalog = catalog;
 65             keyCol.Name = "ID"; 
 66             keyCol.Type = ADOX.DataTypeEnum.adInteger;
 67             keyCol.DefinedSize = 9;
 68             keyCol.Properties["AutoIncrement"].Value = true;
 69             //添加主键
 70             tb.Columns.Append(keyCol, ADOX.DataTypeEnum.adInteger, 0);
 71             tb.Keys.Append("PrimatyKey", ADOX.KeyTypeEnum.adKeyPrimary, "ID", "", "");
 72 
 73             foreach (string colName in columnNames)
 74             {
 75                 tb.Columns.Append(colName, DataTypeEnum.adVarWChar, 64);//DataTypeEnum.adDate;
 76             }
 77             try { catalog.Tables.Append(tb); }
 78             catch (Exception ex) { msg = ex.Message; }
 79             finally { cnn.Close(); catalog = null; tb = null; }
 80 
 81             return msg;
 82         }
 83         /// <summary>
 84         /// ADOX,ADODB修改数据表(失败)
 85         /// </summary>
 86         /// <param name="dbName"></param>
 87         /// <param name="pwd"></param>
 88         /// <param name="tbName"></param>
 89         /// <param name="sql"></param>
 90         /// <returns></returns>
 91         public static string ExecuteSql2Db(string dbName, string pwd, string tbName, string sql)
 92         {
 93             string msg = "";
 94             #region 通过获取实例的表,直接对表进行数据操作,失败;这已经超出了ADOX的范围,应该用OleDB操作
 95             //Catalog catalog = ActivateDB(dbName, pwd, out msg);
 96             //if (!string.IsNullOrEmpty(msg)) return msg;
 97 
 98             //ADOX.Table tb = null;
 99             //if (catalog.Tables.Count <= 0)
100             //    return "数据库实例尚无数据表";
101             //else
102             //    foreach (ADOX.Table t in catalog.Tables)
103             //    {
104             //        if (t.Name.Equals(tbName))
105             //        { tb = t; break; }
106             //    }
107             //if (tb == null) return "未初始化数据表:" + tbName;
108             #endregion
109             //OleDb操作
110 
111             return msg;
112         }
113         /// <summary>
114         /// 修改Access数据库实例密码
115         /// </summary>
116         /// <param name="dbName">数据库实例名(数据库文件)</param>
117         /// <param name="oldPwd">原密码</param>
118         /// <param name="newPwd">新密码</param>
119         /// <returns></returns>
120         public static string ChangePwd(string dbName, string oldPwd, string newPwd)
121         {
122             string conn = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + dbName + ";Jet OLEDB:Database password=" + oldPwd;
123             string sql = "ALTER DATABASE PASSWORD " + newPwd + " " + oldPwd;
124             string msg = "";
125             ADODB.Connection cn = null;
126             try
127             {
128                 cn = new ADODB.Connection();
129                 cn.Mode = ADODB.ConnectModeEnum.adModeShareExclusive;
130                 cn.Open(conn, null, null, -1);
131                 // 执行 SQL 语句以更改密码。
132                 object num;
133                 cn.Execute(sql, out num, -1);
134             }
135             catch (Exception ex) { msg = ex.Message; }
136             finally { cn.Close(); }
137             return msg;
138         }
139     }

操作数据库

 

  1     class OleDBer
  2     {
  3         private static string conStr = "";
  4         private static OleDbConnection _cnn = null;
  5 
  6         private static OleDbConnection OleCnn
  7         {
  8             get
  9             {
 10                 if (_cnn == null)
 11                 {
 12                     _cnn = new OleDbConnection(conStr);
 13                     _cnn.Open();
 14                 }
 15                 else if (_cnn.State == System.Data.ConnectionState.Closed)
 16                 {
 17                     _cnn.Open();
 18                 }
 19                 else if (_cnn.State == System.Data.ConnectionState.Broken)
 20                 {
 21                     _cnn.Close();
 22                     _cnn.Open();
 23                 }
 24                 return _cnn;
 25             }
 26         }
 27         /// <summary>
 28         /// 据Sql修改数据表
 29         /// </summary>
 30         /// <param name="dbName"></param>
 31         /// <param name="pwd"></param>
 32         /// <param name="sql"></param>
 33         /// <returns></returns>
 34         public static string ExecuteSql(string dbName, string pwd, string sql)
 35         {
 36             string msg = "";
 37             conStr=string.IsNullOrEmpty(pwd)?"Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + dbName + ";Persist Security Info=False":
 38                 "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + dbName + ";Persist Security Info=False;Jet OLEDB:Database password=" + pwd;
 39 
 40             using (OleDbCommand oCmd = new OleDbCommand(sql,OleCnn))
 41             {
 42                 try
 43                 {
 44                     oCmd.ExecuteNonQuery();
 45                 }
 46                 catch (Exception ex) { msg = ex.Message; }
 47             }
 48             return msg;
 49         }
 50 
 51         public static DataTable GetDataTable(string dbName, string pwd, string sql,ref string msg)
 52         {
 53             msg = "";
 54             conStr = string.IsNullOrEmpty(pwd) ? "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + dbName + ";Persist Security Info=False" :
 55                 "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + dbName + ";Persist Security Info=False;Jet OLEDB:Database password=" + pwd;
 56 
 57             try
 58             {
 59                 DataSet dataset = new DataSet();
 60                 using (OleDbCommand com = new OleDbCommand(sql, OleCnn))
 61                 {
 62                     OleDbDataAdapter da = new OleDbDataAdapter(com);
 63                     da.Fill(dataset);
 64                 }
 65                 return dataset.Tables[0];
 66             }
 67             catch (Exception ex) { msg = ex.Message; return null; }
 68         }
 69 
 70         public static bool CheckExists(string dbName, string pwd, string sql)
 71         {
 72             string msg="";
 73             DataTable dt = GetDataTable(dbName, pwd, sql, ref msg);
 74             if (dt != null && dt.Rows.Count > 0) return true;
 75             else return false;
 76         }
 77         public static object GetDataValue(string dbName, string pwd, string sql)
 78         {
 79             string msg = "";
 80             DataTable dt = GetDataTable(dbName, pwd, sql, ref msg);
 81             if (dt != null && dt.Rows.Count > 0) return dt.Rows[0][0];
 82             else return DBNull.Value;
 83         }
 84 
 85         public string AddData(string fileName, string pwd)
 86         {
 87             string msg = "";
 88             string strConnection = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=" + fileName + ";Persist Security Info=False;Jet OLEDB:Database password=" + pwd;
 89 
 90             OleDbConnection conn = new OleDbConnection(strConnection);
 91             string strSql = "select * from AdPlayList";
 92             OleDbDataAdapter da = new OleDbDataAdapter(strSql, conn);
 93             DataSet ds = new DataSet();
 94             try
 95             {
 96                 conn.Open();
 97                 da.Fill(ds, "AdPlayList");
 98                 DataRow dr = ds.Tables["AdPlayList"].NewRow();
 99                 dr["FileName"] = "A.wmv";
100                 dr["FileDate"] = DateTime.Now.ToShortDateString();
101                 dr["FileSize"] = 25;
102                 dr["OrderID"] = 1;
103                 dr["Sha1"] = "2q34lkadsflaoiulkj34";
104                 ds.Tables["AdPlayList"].Rows.Add(dr);
105                 OleDbCommandBuilder cb = new OleDbCommandBuilder(da);
106                 da.Update(ds, "AdPlayList");
107                 ds.AcceptChanges();
108             }
109             catch (Exception ex)
110             {
111                 //MessageBox.Show(ex.Message);
112                 msg = ex.Message;
113             }
114             finally
115             {
116                 da.Dispose();
117                 conn.Dispose();
118                 conn.Close();
119             }
120             return msg;
121         }
122 
123     }

操作数据表