通过DataSet更新、插入数据库

方法一：
 //与SQL Server的连接字符串设置
 private string _connString;
 private string _strSql;
 private SqlCommandBuilder sqlCmdBuilder;
 private DataSet ds = new DataSet();
 private SqlDataAdapter da;
 public sqlAccess(string connString,string strSql)
 {
      this._connString=connString;
 }
 private SqlConnection GetConn() 
 { 
      try 
      { 
           SqlConnection Connection = new SqlConnection(this._connString); 
           Connection.Open(); 
           return Connection; 
      } 
      catch (Exception ex) 
      { 
           MessageBox.Show(ex.Message,"数据库连接失败");
           throw;
      } 
 }
 //根据输入的SQL语句检索数据库数据
 public DataSet SelectDb(string strSql,string strTableName)
 { 
      try
      {
          this._strSql = strSql;
          this.da = new SqlDataAdapter(this._strSql,this.GetConn());
          this.ds.Clear();
          this.da.Fill(ds,strTableName);
          return ds;//返回填充了数据的DataSet，其中数据表以strTableName给出的字符串命名
      }
      catch (Exception ex) 
      { 
           MessageBox.Show(ex.Message,"数据库操作失败");
           throw;
      } 
 }
 //数据库数据更新(传DataSet和DataTable的对象)
 public DataSet UpdateDs(DataSet changedDs,string tableName)
 {
      try
      {
          this.da = new SqlDataAdapter(this._strSql,this.GetConn());
          this.sqlCmdBuilder = new SqlCommandBuilder(da);
          this.da.Update(changedDs,tableName);
          changedDs.AcceptChanges();
          return changedDs;//返回更新了的数据库表
      }
      catch (Exception ex) 
      { 
           MessageBox.Show(ex.Message,"数据库更新失败");
           throw;
      } 
}
 
 
1. GetConn方法创建一个数据库连接，返回SqlConnection。 
2.使用的select命令中必须包含主键，这点大家都知道的! 
3. this.da.Fill(ds,strTableName) 填充数据集 
4.构造CommandBuilder对象时,将DataAdapter对象作为构造函数参数传入: 
  this.sqlCmdBuilder = new SqlCommandBuilder(da); 
5. 在调用UpdateDs()更新数据库前，请检查changedDs是否已经被更新过，用changedDs.[tableName] GetChanges() != null; 
6.用this.da.Update(changedDs,tableName)方法更新数据,然后调用changedDs.AcceptChanges()才能真正的更新数据库，调用 changedDs.RejectChanges() 取消更新。 

方法二：
该方法可能存在性能问题
            int tab1Count = ds.Tables["ruledetail_setup"].Rows.Count;
            for (int i = 0; i < tab1Count; i++)
            {
                string sql = "select count(*) from ruledetail_setup where type = " + type + " and ID = ";
                    sql += ds.Tables["ruledetail_setup"].Rows[i]["ID"];
                if (Convert.ToInt32(SqlHelper.ExecuteScalar(CommandType.Text, sql, null)) != 0)
                {
                    string sqlUpdata = "updata ruledetail_setup set errorLimit={0},scoreInterval={1},detailRule={2},gradeTime={3} ";
                    sqlUpdata += "where type = " + type + " and ID = " + ds.Tables["ruledetail_setup"].Rows[i]["ID"];
                    String.Format(sqlUpdata,
                        ds.Tables["ruledetail_setup"].Rows[i]["errorLimit"],
                        ds.Tables["ruledetail_setup"].Rows[i]["scoreInterval"],
                        ds.Tables["ruledetail_setup"].Rows[i]["detailRule"],
                        ds.Tables["ruledetail_setup"].Rows[i]["gradeTime"]);
                    SqlHelper.ExecuteNonQuery(CommandType.Text, sqlUpdata, null);
                }
                else
                {
                    string sqlIns = "insert into ruledetail_setup (Type,ID,errorLimit,scoreInterval,detailRule,gradeTime) ";
                        sqlIns += "values ("+type+",{0},{1},{2},{3},{4})";
                    String.Format(sqlIns,
                        ds.Tables["ruledetail_setup"].Rows[i]["ID"],
                        ds.Tables["ruledetail_setup"].Rows[i]["errorLimit"],
                        ds.Tables["ruledetail_setup"].Rows[i]["scoreInterval"],
                        ds.Tables["ruledetail_setup"].Rows[i]["detailRule"],
                        ds.Tables["ruledetail_setup"].Rows[i]["gradeTime"]);
                    SqlHelper.ExecuteNonQuery(CommandType.Text, sqlIns, null);
                }
            }