2: using System.Data;

   3: using System.Data.SqlClient;

   4:  

   5:  

   6: namespace QxtIntface

   7: {

   8:     class DBCom

   9:     {

  10:         // 获取与数据库的连接

  11:         public static SqlConnection GetSqlConnection()

  12:         {

  13:             try

  14:             {

  15:                 SqlConnection scon = new SqlConnection(Global.sConStr);

  16:                 return scon;

  17:             }

  18:             catch(Exception ex)

  19:             { 

  20:                 System.Windows.Forms.MessageBox.Show("数据库连接错误！"+ex.Message);

  21:                 return null;

  22:             }

  23:         }

  24:         public static SqlConnection GetSqlConnection(string sConStr)

  25:         {

  26:             try

  27:             {

  28:                 SqlConnection scon = new SqlConnection(sConStr);

  29:                 return scon;

  30:             }

  31:             catch (Exception ex)

  32:             {

  33:                 System.Windows.Forms.MessageBox.Show("数据库连接错误！" + ex.Message);

  34:                 return null;

  35:             }

  36:         }

  37:         

  38:         // 返回指定数据库的数据集

  39:         public static DataSet GetExeQuery(string selectCmd)

  40:         {

  41:             SqlConnection con = GetSqlConnection();

  42:             con.Open();

  43:             DataSet ds = new DataSet();

  44:             SqlDataAdapter da = new SqlDataAdapter(selectCmd, con);

  45:             da.Fill(ds);

  46:             con.Close();

  47:             return ds;

  48:         }

  49:  

  50:         // 执行非查询命令

  51:         public static int ExeNoneQuery(string sCmd)

  52:         {

  53:             int nResult;

  54:             SqlConnection con = GetSqlConnection();

  55:             con.Open();

  56:             SqlCommand cmd = new SqlCommand(sCmd, con);

  57:             nResult = cmd.ExecuteNonQuery();

  58:             return nResult;

  59:         }

  60:  

  61:         //返回数据查询的第一个字段值(查询指定表的数据行数)

  62:         public static int ExeScalar(string selectTableName)

  63:         {

  64:             string selectCmd = "select count * from " + selectTableName;

  65:             SqlConnection con = GetSqlConnection();

  66:             con.Open();

  67:             SqlCommand cmd = new SqlCommand(selectCmd, con);

  68:             return Convert.ToInt32(cmd.ExecuteScalar());

  69:         }

  70:     }

  71: }