.net中的事务

private void btnTransfer_Click(object sender, System.EventArgs e)

{

lblAccount1.Text=" ";

lblAccount2.Text=" ";

int CurrBalance; 

string strSQL = "Select Balance FROM Account where AccNo='"+txtFrom.Text+"'" ;

  

SqlConnection objSqlConnection = new SqlConnection("server=VIJAYK;uid=sa;pwd=playware;database=Account");

objSqlConnection.Open();

SqlDataReader objReader;

SqlCommand objSqlCommand = new SqlCommand(strSQL,objSqlConnection);

SqlTransaction objSqlTransaction =objSqlConnection.BeginTransaction();

objSqlCommand.Transaction=objSqlTransaction;

try

{

objReader = objSqlCommand.ExecuteReader();

objReader.Read();

CurrBalance = Convert.ToInt32(objReader.GetValue(0));

objReader.Close();

if (CurrBalance < Convert.ToInt32(txtAmount.Text))

{

throw(new Exception("转帐金额不足"));

}

strSQL = "Update Account set Balance = Balance - " + txtAmount.Text + " where AccNo = '" + Convert.ToInt32(txtFrom.Text) + "'";

objSqlCommand.CommandText=strSQL;

objSqlCommand.ExecuteNonQuery();  

lblAccount1.Text="帐户 " + txtFrom.Text +" 成功记入借方";

strSQL = "Update Account set Balance =  Balance + "+ txtAmount.Text + " where AccNo = '" + Convert.ToInt32(txtTo.Text) + "'";

objSqlCommand.CommandText = strSQL;

objSqlCommand.ExecuteNonQuery();

lblAccount2.Text="帐户 " + txtTo.Text +" 成功记入贷方";

objSqlTransaction.Commit();

lblException.Text = "成功将金额 " + txtAmount.Text + " 从帐户 " + txtFrom.Text + " 转帐到帐户 " + txtTo.Text + " 。";;

}

catch(Exception ex)

{

objSqlTransaction.Rollback();

lblException.Text = "错误：" + ex.Message;

}

finally

{

objSqlConnection.Close();

}

}