using System;using System.Data;using System.Data.SqlClient;namespace Whir.Software.Framework.Ultimate{    /// 
    ///     数据库访问助手    /// 
    public class DbHelper    {        #region 判断连接是否成功        /// 
        ///     判断连接是否成功！        /// 
        ///  链接字符串        /// 
    
     true 表示链接成功，false表示连接失败
            public static bool IsConnected(string con)        {            bool flag;            var conn = new SqlConnection(con);            try            {                conn.Open();                flag = true;            }            catch (Exception)            {                flag = false;            }            finally            {                conn.Close();            }            return flag;        }        #endregion        #region 执行不带参数sql语句        /// 
        ///     执行不带参数sql语句        /// 
        /// 增，删，改sql语句        ///         /// 
    
     返回所影响的行数
            public static bool Execute(string sql, string con)        {            var cmd = new SqlCommand();            var connection = new SqlConnection(con);            try            {                using (connection)                {                    cmd.Connection = connection;                    cmd.CommandText = sql;                    connection.Open();                    cmd.ExecuteNonQuery();                    return true;                }            }            catch (Exception)            {                return false;            }        }        #endregion        #region 执行SQL语句返回DataTable        /// 
        ///     执行SQL语句返回DataTable        /// 
        ///         ///         /// 
            public static DataTable ExcuteDataTable(string sql, string con)        {            var cmd = new SqlCommand();            var connection = new SqlConnection(con);            try            {                using (connection)                {                    cmd.Connection = connection;                    cmd.CommandText = sql;                    connection.Open();                    var da = new SqlDataAdapter(cmd);                    var ds = new DataSet();                    da.Fill(ds);                    return ds.Tables[0];                }            }            catch (Exception ex)            {                var dt = new DataTable();                dt.Columns.Add("异常信息");                DataRow row = dt.NewRow();                row["异常信息"] = ex.Message;                dt.Rows.Add(row);                return dt;            }        }        #endregion        #region 执行SQL语句查询单条记录        /// 
        ///     执行SQL语句查询单条记录        /// 
        ///         ///         /// 
            public static object ExecuteScalar(string sql, string con)        {            var cmd = new SqlCommand();            var connection = new SqlConnection(con);            try            {                using (connection)                {                    cmd.Connection = connection;                    cmd.CommandText = sql;                    connection.Open();                    return cmd.ExecuteScalar();                }            }            catch (Exception)            {                return string.Empty;            }        }        #endregion        #region 取得表最大Id        /// 
        ///     取得表最大Id        /// 
        ///         ///         ///         /// 
            public static int GetMaxId(string tableName, string fieldName, string con)        {            string sql = "SELECT NVL(MAX({0}),0)+1 FROM {1}";            try            {                sql = string.Format(sql, fieldName, tableName);                int result;                Int32.TryParse(ExecuteScalar(sql, con).ToString(), out result);                return result;            }            catch (Exception)            {                return -1;            }        }        #endregion    }}

作者：a497785609 发表于2014-6-1 15:06:22

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