String connectionString = ConfigurationManager.ConnectionStrings["DB_Constr"].ToString();
SqlConnection conn = null;
SqlTransaction trans = null;
try {
 conn = new SqlConnection(connectionString);
 if (conn.State != ConnectionState.Open) conn.Open();
 //開啟事務(wù)，可以指定事無級別。默認(rèn)為提交才可以查詢
 trans = conn.BeginTransaction();
 //save(conn, trans);
 DbUtils.commit(trans);
} catch (Exception ex) {
 DbUtils.rollback(trans);
 ClientScript.RegisterStartupScript(this.GetType(), "錯誤提示", "<script>alert('" + StringUtil.toJsStr(ex.Message) + "');</script>");
} finally {
 DbUtils.closeQuietly(conn, trans);
}
String connectionString = ConfigurationManager.ConnectionStrings["DB_Constr"].ToString();
SqlConnection conn = null;
try {
 conn = new SqlConnection(connectionString);
 if (conn.State != ConnectionState.Open) conn.Open();
} catch (Exception ex) {
 ScriptManager.RegisterStartupScript(this, this.GetType(), "mess", "<script>alert('"+StringUtil.toJsStr(ex.Message)+"')</script>", false);
} finally {
 DbUtils.closeQuietly(conn);
}

using System;
using System.Collections.Generic;
using System.Text;
namespace Tools{
 public sealed class StringUtil {
  public static bool isEmpty(String str) {
   if (str == null) return true;
   if (str.Length == 0) return true;
   if (str == String.Empty) return true;
   return false;
  }
  public static bool isNotEmpty(String str) {
   return !isEmpty(str);
  }
  public static String toJsStr(String str) {
   str = str.Replace("'", "\\'");
   str = str.Replace("\r", "");
   str = str.Replace("\n", "\\n");
   return str;
  }
  public static void Main() {
   Console.Write(isNotEmpty(null));
   Console.Read();
  }
 }
}

using System;
using System.Collections.Generic;
using System.Text;
using System.Data.SqlClient;
using System.Data;
namespace Tools{
 public class DbUtils {
  public static SqlConnection getConnection(string connectstr) {
   SqlConnection conn = new SqlConnection(connectstr);
   if (conn.State != ConnectionState.Open) {
    conn.Open();
   }
   return conn;
  }
  public static void closeQuietly(SqlConnection conn) {
   try {
    close(conn);
   } catch { }
  }
  public static void closeQuietly(SqlTransaction trans) {
   try {
    close(trans);
   } catch { }
  }
  public static void close(SqlConnection conn) {
   if (conn != null) {
    conn.Close();
    conn.Dispose();
   }
  }
  public static void close(SqlTransaction trans) {
   if (trans != null) {
    trans.Dispose();
   }
  }
  public static void closeQuietly(SqlConnection conn, SqlTransaction trans) {
   closeQuietly(trans);
   closeQuietly(conn);
  }
  public static void commit(SqlTransaction trans) {
   try {
    if(trans!=null) trans.Commit();
   } catch{ }
  }
  public static void rollback(SqlTransaction trans) {
   try {
    if (trans != null) trans.Rollback();
   } catch { }
  }
 }
}