数据连接类

数据连接类 using System; using System.Data; using System.Data.OleDb; using System.IO; namespace Too.CommonLibrary { public class LinkDataBase { private string strSQL; //与SQL Server的连接字符串设置 public string connectionString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=HuaYunProjectManagementDB.mdb"; //与数据库的连接 private OleDbConnection myConnection; private OleDbCommandBuilder oleCmdBld; private DataSet ds = new DataSet(); private OleDbDataAdapter da; public LinkDataBase() { this.connectionString = string.Format("Provider=Microsoft.Jet.OLEDB.4.0;Data Source={0}", Path.Combine(System.Environment.CurrentDirectory, "HuaYunProjectManagementDB.mdb")); } //根据输入的SQL语句检索数据库数据 public DataSet SelectDataBase(string tempStrSQL, string tempTableName) { this.strSQL = tempStrSQL; this.myConnection = new OleDbConnection(connectionString); this.da = new OleDbDataAdapter(this.strSQL, this.myConnection); this.ds.Clear(); this.da.Fill(ds, tempTableName); return ds;//返回填充了数据的DataSet，其中数据以tempTableName给出 的字符串命名 } //数据库数据更新(传DataSet和DataTable表名对象) public DataSet UpdateDataBase(DataSet changedDataSet, string tableName) { this.myConnection = new OleDbConnection(connectionString); this.da = new OleDbDataAdapter(this.strSQL, this.myConnection); this.oleCmdBld = new OleDbCommandBuilder(da); this.da.Update(changedDataSet, tableName); return changedDataSet;//返回更新了的数据库表 } //检索数据库数据(传字符串,直接操作数据库) public DataTable SelectDataBase(string tempStrSQL) { this.myConnection = new OleDbConnection(connectionString); DataSet tempDataSet = new DataSet(); this.da = new OleDbDataAdapter(tempStrSQL, this.myConnection); this.da.Fill(tempDataSet); return tempDataSet.Tables[0]; } //数据库数据更新(传字符串，直接操作数据库) public int UpdateDataBase(string tempStrSQL) { this.myConnection = new OleDbConnection(connectionString); //使用Command之前一定要先打开连接,后关闭连接,而DataAdapter则会 自动打开关闭连接 myConnection.Open(); OleDbCommand tempOleCommand = new OleDbCommand(tempStrSQL, this.myConnection); int intNumber = tempOleCommand.ExecuteNonQuery();//返回数据库中影响 的行数 myConnection.Close(); return intNumber; } } }