几次装机，Notes已烟消云散，近日因为Node.js死活搞不定，无奈装机，备份好的东东，没想到磁盘扇区出现异常，可能是PE启动盘的病毒，只好将磁盘全部重新分区，恢复数据也懒得恢复了,日积月累关乎将来的开发效率，还好处于懵懂阶段。笔记一大堆，记忆力又不怎么好，所以web+log=blog;
SqlHelper类
using System;
using System.Collections.Generic;
using System.Configuration;
using System.Data;
using System.Data.SqlClient;
using System.Linq;
using System.Text;
using System.Threading.Tasks;namespace DAL
{/// <summary>
/// SqlHelper类 by zy 2016-3-11
/// </summary>
public class SqlHelper
{
//如果项目中只连接了一个数据库 那么可以在此定义一个固定的连接字符串 public static string ConnectionStr { get; } =
ConfigurationManager.ConnectionStrings["connStr"].ConnectionString; public static string ConnStr()
{
return ConfigurationManager.ConnectionStrings["connStr"].ConnectionString;
}
#region ExecuteNonQuery /// <summary>
/// 执行sql语句 返回受影响行数
/// </summary>
/// <param name="connectionString">连接字符串</param>
/// <param name="cmdType">command类型</param>
/// <param name="cmdText">sql语句</param>
/// <param name="commandParameters">参数</param>
/// <returns></returns>
public static int ExecuteNonQuery(string connectionString, CommandType cmdType, string cmdText,
params SqlParameter[] commandParameters)
{
SqlCommand cmd = new SqlCommand(); using (SqlConnection conn = new SqlConnection(connectionString))
{
PrepareCommand(cmd, conn, null, cmdType, cmdText, commandParameters);
int val = cmd.ExecuteNonQuery();
cmd.Parameters.Clear();
return val;
}
} /// <summary>
/// 执行sql语句 返回当前插入的记录id(其实是ExecuteScalar转换成id返回)
/// </summary>
/// <param name="connectionString">连接字符串</param>
/// <param name="cmdType">command类型</param>
/// <param name="cmdText">sql语句</param>
/// <param name="returnID">返回id</param>
/// <param name="commandParameters">参数</param>
/// <returns></returns>
public static int ExecuteNonQuery(string connectionString, CommandType cmdType, string cmdText,
out int returnID, params SqlParameter[] commandParameters)
{
SqlCommand cmd = new SqlCommand(); using (SqlConnection conn = new SqlConnection(connectionString))
{
returnID = 0;
PrepareCommand(cmd, conn, null, cmdType, cmdText, commandParameters);
returnID = (Int32) cmd.ExecuteScalar();
cmd.Parameters.Clear();
return returnID;
}
} /// <summary>
/// 执行sql语句 返回受影响行数(数据库连接SqlConnection)
/// </summary>
/// <param name="connection">SqlConnection连接</param>
/// <param name="cmdType">command类型</param>
/// <param name="cmdText">sql语句</param>
/// <param name="commandParameters">参数</param>
/// <returns></returns>
public static int ExecuteNonQuery(SqlConnection connection, CommandType cmdType, string cmdText,
params SqlParameter[] commandParameters)
{
SqlCommand cmd = new SqlCommand(); PrepareCommand(cmd, connection, null, cmdType, cmdText, commandParameters);
int val = cmd.ExecuteNonQuery();
cmd.Parameters.Clear();
return val;
} /// <summary>
/// 执行sql语句 返回受影响行数(事务SqlTransaction)
/// </summary>
/// <param name="trans">SqlTransaction事务</param>
/// <param name="cmdType">command类型</param>
/// <param name="cmdText">sql语句</param>
/// <param name="commandParameters">参数</param>
/// <returns></returns>
public static int ExecuteNonQuery(SqlTransaction trans, CommandType cmdType, string cmdText,
params SqlParameter[] commandParameters)
{
SqlCommand cmd = new SqlCommand();
PrepareCommand(cmd, trans.Connection, trans, cmdType, cmdText, commandParameters);
int val = cmd.ExecuteNonQuery();
cmd.Parameters.Clear();
return val;
} #endregion
#region ExecuteScalar
/// <summary>
/// 执行sql语句 返回结果集第一行第一列
/// </summary>
/// <param name="connectionString">连接字符串</param>
/// <param name="cmdType">Command类型</param>
/// <param name="cmdText">sql语句</param>
/// <param name="commandParameters">参数</param>
/// <returns></returns>
public static object ExecuteScalar(string connectionString, CommandType cmdType, string cmdText,
params SqlParameter[] commandParameters)
{
SqlCommand cmd = new SqlCommand(); using (SqlConnection connection = new SqlConnection(connectionString))
{
PrepareCommand(cmd, connection, null, cmdType, cmdText, commandParameters);
object val = cmd.ExecuteScalar();
cmd.Parameters.Clear();
return val;
}
} /// <summary>
/// 执行sql语句 返回结果集第一行第一列(事务)
/// </summary>
/// <param name="trans">SqlTransaction事务</param>
/// <param name="cmdType">Command类型</param>
/// <param name="cmdText">sql语句</param>
/// <param name="commandParameters">参数</param>
/// <returns></returns>
public static object ExecuteScalar(SqlTransaction trans, CommandType cmdType, string cmdText,
params SqlParameter[] commandParameters)
{
SqlCommand cmd = new SqlCommand();
PrepareCommand(cmd, trans.Connection, trans, cmdType, cmdText, commandParameters);
object val = cmd.ExecuteScalar();
cmd.Parameters.Clear();
return val;
} /// <summary>
/// 执行sql语句 返回结果集第一行第一列(数据库连接)
/// </summary>
/// <param name="connection">SqlConnection连接</param>
/// <param name="cmdType">Command类型</param>
/// <param name="cmdText">sql语句</param>
/// <param name="commandParameters">参数</param>
/// <returns></returns>
public static object ExecuteScalar(SqlConnection connection, CommandType cmdType, string cmdText,
params SqlParameter[] commandParameters)
{
SqlCommand cmd = new SqlCommand(); PrepareCommand(cmd, connection, null, cmdType, cmdText, commandParameters);
object val = cmd.ExecuteScalar();
cmd.Parameters.Clear();
return val;
} #endregion
#region ExecuteReader
/// <summary>
/// 执行sql语句 返回reader
/// </summary>
/// <param name="connectionString">连接字符串</param>
/// <param name="cmdType">command类型</param>
/// <param name="cmdText">sql语句</param>
/// <param name="commandParameters">参数</param>
/// <returns></returns>
public static SqlDataReader ExecuteReader(string connectionString, CommandType cmdType, string cmdText,
params SqlParameter[] commandParameters)
{
SqlCommand cmd = new SqlCommand();
SqlConnection conn = new SqlConnection(connectionString);
try
{
PrepareCommand(cmd, conn, null, cmdType, cmdText, commandParameters);
SqlDataReader rdr = cmd.ExecuteReader(CommandBehavior.CloseConnection);
cmd.Parameters.Clear();
return rdr;
}
catch
{
conn.Close();
throw;
}
} #endregion
#region DataSet
/// <summary>
/// 执行sql语句 返回DataSet结果集(无参数)
/// </summary>
/// <param name="connectionString">连接字符串</param>
/// <param name="commandType">command类型</param>
/// <param name="commandText">sql语句</param>
/// <returns></returns>
public static DataSet ExecuteDataset(string connectionString, CommandType commandType, string commandText)
{
return ExecuteDataset(connectionString, commandType, commandText, (SqlParameter[]) null);
} /// <summary>
/// 执行sql语句 返回DataSet结果集
/// </summary>
/// <param name="connectionString">连接字符串</param>
/// <param name="commandType">command类型</param>
/// <param name="commandText">sql语句</param>
/// <param name="commandParameters">参数</param>
/// <returns></returns>
public static DataSet ExecuteDataset(string connectionString, CommandType commandType, string commandText,
params SqlParameter[] commandParameters)
{
//创建数据库连接 完成后dispose
using (SqlConnection cn = new SqlConnection(connectionString))
{
cn.Open(); //根据数据库连接 调用具体方法
return ExecuteDataset(cn, commandType, commandText, commandParameters);
}
} /// <summary>
/// 执行sql语句 返回DataSet结果集(数据库连接SqlConnection)
/// </summary>
/// <param name="connection">SqlConnection连接</param>
/// <param name="commandType">command类型</param>
/// <param name="commandText">sql语句</param>
/// <param name="commandParameters">参数</param>
/// <returns></returns>
public static DataSet ExecuteDataset(SqlConnection connection, CommandType commandType, string commandText,
params SqlParameter[] commandParameters)
{
//创建command
SqlCommand cmd = new SqlCommand();
//准备command对象
PrepareCommand(cmd, connection, (SqlTransaction) null, commandType, commandText, commandParameters); //创建SqlDataAdapter和DataSet
SqlDataAdapter da = new SqlDataAdapter(cmd);
DataSet ds = new DataSet(); //把结果集装进dataset
da.Fill(ds); //返回
return ds;
} #endregion DataSet
#region DataTable
/// <summary>
/// 执行sql语句 返回DataTable结果集(无参数)
/// </summary>
/// <param name="connectionString">连接字符串</param>
/// <param name="commandType">command类型</param>
/// <param name="commandText">sql语句</param>
/// <returns></returns>
public static DataTable ExecuteDataTable(string connectionString, CommandType commandType, string commandText)
{
return ExecuteDataTable(connectionString, commandType, commandText, (SqlParameter[])null);
} /// <summary>
/// 执行sql语句 返回DataTable结果集
/// </summary>
/// <param name="connectionString">连接字符串</param>
/// <param name="commandType">command类型</param>
/// <param name="commandText">sql语句</param>
/// <param name="commandParameters">参数</param>
/// <returns></returns>
public static DataTable ExecuteDataTable(string connectionString, CommandType commandType, string commandText,
params SqlParameter[] commandParameters)
{
using (SqlConnection cn = new SqlConnection(connectionString))
{
cn.Open();
return ExecuteDataTable(cn, commandType, commandText, commandParameters);
}
} /// <summary>
/// 执行sql语句 返回DataTable结果集
/// </summary>
/// <param name="connection">SqlConnection连接</param>
/// <param name="commandType">command类型</param>
/// <param name="commandText">sql语句</param>
/// <param name="commandParameters">参数</param>
/// <returns></returns>
public static DataTable ExecuteDataTable(SqlConnection connection, CommandType commandType, string commandText,
params SqlParameter[] commandParameters)
{
SqlCommand cmd = new SqlCommand();
PrepareCommand(cmd, connection, (SqlTransaction) null, commandType, commandText, commandParameters); SqlDataAdapter da = new SqlDataAdapter(cmd);
DataTable dt = new DataTable(); da.Fill(dt);
return dt;
} #endregion DataTable
#region PrepareCommand
/// <summary>
/// 准备Command对象
/// </summary>
/// <param name="cmd">SqlCommand 对象</param>
/// <param name="conn">SqlConnection 对象</param>
/// <param name="trans">SqlTransaction 对象</param>
/// <param name="cmdType">Command 类型</param>
/// <param name="cmdText">sql语句</param>
/// <param name="cmdParms">参数</param>
private static void PrepareCommand(SqlCommand cmd, SqlConnection conn, SqlTransaction trans,
CommandType cmdType, string cmdText, SqlParameter[] cmdParms)
{
//打开SqlConnection连接
if (conn.State != ConnectionState.Open)
conn.Open();
//给Command的Connection CommandText设置值
cmd.Connection = conn;
cmd.CommandText = cmdText;
//如果是事务 设置事务
if (trans != null)
cmd.Transaction = trans;
//Command类型
cmd.CommandType = cmdType;
//Command参数
if (cmdParms != null)
{
foreach (SqlParameter parm in cmdParms)
{
//在此可以操作参数 比如把参数值里的英文逗号全部改为中文逗号 或者其他操作
switch (parm.SqlDbType)
{
case SqlDbType.Char:
case SqlDbType.NChar:
case SqlDbType.NText:
case SqlDbType.NVarChar:
case SqlDbType.Text:
case SqlDbType.VarChar:
if (parm.Value != null && parm.Value != DBNull.Value && parm.ParameterName != "@SQLClause")
{
string tmp = parm.Value.ToString();
tmp = tmp.Replace(",", "，");
tmp = tmp.Replace("'", "＇");
parm.Value = tmp;
}
break;
}//把参数添加到Command中的Parameters中
cmd.Parameters.Add(parm);
}
}
}#endregion
}}
原文地址不得，忘记哪里CV的了。