代码:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Text;
using System.Data;
using System.Collections;
using MySql.Data.MySqlClient;
using MySql.Data.Types;
using System.Configuration;
using System.IO; namespace ADT.TuDou.DALProfile
{
public class MySqlDBHelper
{
//Get the database connectionstring, which are static variables and readonly, all project documents can be used directly, but can not modify it
//the database connectionString
//public static string ConnectionStringManager
//{
// get { return connectionStringManager; }
//} //This connectionString for the local test
//public static readonly string connectionStringManager = System.Configuration.ConfigurationManager.ConnectionStrings["MySQLConnString"].ConnectionString;
//ConfigurationManager.ConnectionStrings["MySQLConnString"].ConnectionString; //hashtable to store the parameter information, the hash table can store any type of argument
//Here the hashtable is static types of static variables, since it is static, that is a definition of global use.
//All parameters are using this hash table, how to ensure that others in the change does not affect their time to read it
//Before ,the method can use the lock method to lock the table, does not allow others to modify.when it has readed then unlocked table.
//Now .NET provides a HashTable's Synchronized methods to achieve the same function, no need to manually lock, completed directly by the system framework
private static Hashtable parmCache = Hashtable.Synchronized(new Hashtable()); /// <summary>
/// Execute a SqlCommand command that does not return value, by appointed and specified connectionstring
/// The parameter list using parameters that in array forms
/// </summary>
/// <remarks>
/// Usage example:
/// int result = ExecuteNonQuery(connString, CommandType.StoredProcedure,
/// "PublishOrders", new MySqlParameter("@prodid", 24));
/// </remarks>
/// <param name="connectionString">a valid database connectionstring</param>
/// <param name="cmdType">MySqlCommand command type (stored procedures, T-SQL statement, and so on.) </param>
/// <param name="cmdText">stored procedure name or T-SQL statement</param>
/// <param name="commandParameters">MySqlCommand to provide an array of parameters used in the list</param>
/// <returns>Returns a value that means number of rows affected/returns>
public static int ExecuteNonQuery(string connectionString, CommandType cmdType, string cmdText, params MySqlParameter[] commandParameters)
{
MySqlCommand cmd = new MySqlCommand(); using (MySqlConnection conn = new MySqlConnection(connectionString))
{
PrepareCommand(cmd, conn, null, cmdType, cmdText, commandParameters);
int val = cmd.ExecuteNonQuery();
cmd.Parameters.Clear();
return val;
}
} /// <summary>
/// Execute a SqlCommand command that does not return value, by appointed and specified connectionstring
/// The parameter list using parameters that in array forms
/// </summary>
/// <remarks>
/// Usage example:
/// int result = ExecuteNonQuery(connString, CommandType.StoredProcedure,
/// "PublishOrders", new MySqlParameter("@prodid", 24));
/// </remarks>
/// <param name="cmdType">MySqlCommand command type (stored procedures, T-SQL statement, and so on.) </param>
/// <param name="connectionString">a valid database connectionstring</param>
/// <param name="cmdText">stored procedure name or T-SQL statement</param>
/// <param name="commandParameters">MySqlCommand to provide an array of parameters used in the list</param>
/// <returns>Returns true or false </returns>
public static bool ExecuteNonQuery(CommandType cmdType, string connectionString, string cmdText, params MySqlParameter[] commandParameters)
{
MySqlCommand cmd = new MySqlCommand(); using (MySqlConnection conn = new MySqlConnection(connectionString))
{
PrepareCommand(cmd, conn, null, cmdType, cmdText, commandParameters);
try
{
int val = cmd.ExecuteNonQuery();
return true;
}
catch
{
return false;
}
finally
{
cmd.Parameters.Clear();
}
}
}
/// <summary>
/// Execute a SqlCommand command that does not return value, by appointed and specified connectionstring
/// Array of form parameters using the parameter list
/// </summary>
/// <param name="conn">connection</param>
/// <param name="cmdType">MySqlCommand command type (stored procedures, T-SQL statement, and so on.)</param>
/// <param name="cmdText">stored procedure name or T-SQL statement</param>
/// <param name="commandParameters">MySqlCommand to provide an array of parameters used in the list</param>
/// <returns>Returns a value that means number of rows affected</returns>
public static int ExecuteNonQuery(MySqlConnection conn, CommandType cmdType, string cmdText, params MySqlParameter[] commandParameters)
{
MySqlCommand cmd = new MySqlCommand();
PrepareCommand(cmd, conn, null, cmdType, cmdText, commandParameters);
int val = cmd.ExecuteNonQuery();
cmd.Parameters.Clear();
return val;
} /// <summary>
/// Execute a SqlCommand command that does not return value, by appointed and specified connectionstring
/// Array of form parameters using the parameter list
/// </summary>
/// <param name="conn">sql Connection that has transaction</param>
/// <param name="cmdType">SqlCommand command type (stored procedures, T-SQL statement, and so on.)</param>
/// <param name="cmdText">stored procedure name or T-SQL statement</param>
/// <param name="commandParameters">MySqlCommand to provide an array of parameters used in the list</param>
/// <returns>Returns a value that means number of rows affected </returns>
public static int ExecuteNonQuery(MySqlTransaction trans, CommandType cmdType, string cmdText, params MySqlParameter[] commandParameters)
{
MySqlCommand cmd = new MySqlCommand();
PrepareCommand(cmd, trans.Connection, trans, cmdType, cmdText, commandParameters);
int val = cmd.ExecuteNonQuery();
cmd.Parameters.Clear();
return val;
} /// <summary>
/// Call method of sqldatareader to read data
/// </summary>
/// <param name="connectionString">connectionstring</param>
/// <param name="cmdType">command type, such as using stored procedures: CommandType.StoredProcedure</param>
/// <param name="cmdText">stored procedure name or T-SQL statement</param>
/// <param name="commandParameters">parameters</param>
/// <returns>SqlDataReader type of data collection</returns>
public static MySqlDataReader ExecuteReader(string connectionString, CommandType cmdType, string cmdText, params MySqlParameter[] commandParameters)
{
MySqlCommand cmd = new MySqlCommand();
MySqlConnection conn = new MySqlConnection(connectionString); // we use a try/catch here because if the method throws an exception we want to
// close the connection throw code, because no datareader will exist, hence the
// commandBehaviour.CloseConnection will not work
try
{
PrepareCommand(cmd, conn, null, cmdType, cmdText, commandParameters);
MySqlDataReader rdr = cmd.ExecuteReader(CommandBehavior.CloseConnection);
cmd.Parameters.Clear();
return rdr;
}
catch
{
conn.Close();
throw;
}
} /// <summary>
/// use the ExectueScalar to read a single result
/// </summary>
/// <param name="connectionString">connectionstring</param>
/// <param name="cmdType">command type, such as using stored procedures: CommandType.StoredProcedure</param>
/// <param name="cmdText">stored procedure name or T-SQL statement</param>
/// <param name="commandParameters">parameters</param>
/// <returns>a value in object type</returns>
public static object ExecuteScalar(string connectionString, CommandType cmdType, string cmdText, params MySqlParameter[] commandParameters)
{
MySqlCommand cmd = new MySqlCommand(); using (MySqlConnection connection = new MySqlConnection(connectionString))
{
PrepareCommand(cmd, connection, null, cmdType, cmdText, commandParameters);
object val = cmd.ExecuteScalar();
cmd.Parameters.Clear();
return val;
}
}
public static DataTable ExecuteDataTable(string connectionString, string cmdText, params MySqlParameter[] commandParameters)
{
DataSet retSet = new DataSet();
using (MySqlDataAdapter msda = new MySqlDataAdapter(cmdText, connectionString))
{
msda.Fill(retSet);
}
if (retSet != null && retSet.Tables.Count > )
{
return retSet.Tables[];
}
return null;
}
public static DataTable ExecuteDataTable(string connectionString, CommandType cmdType, string cmdText, params MySqlParameter[] commandParameters)
{
DataSet retSet = new DataSet();
MySqlCommand cmd = new MySqlCommand();
using (MySqlConnection connection = new MySqlConnection(connectionString))
{
PrepareCommand(cmd, connection, null, cmdType, cmdText, commandParameters);
using (MySqlDataAdapter msda = new MySqlDataAdapter(cmd))
{
msda.Fill(retSet);
}
}
if (retSet != null && retSet.Tables.Count > )
{
return retSet.Tables[];
}
return null;
}
public static DataSet GetDataSet(string connectionString, string cmdText, params MySqlParameter[] commandParameters)
{
DataSet retSet = new DataSet();
using (MySqlDataAdapter msda = new MySqlDataAdapter(cmdText, connectionString))
{
msda.Fill(retSet);
}
return retSet;
} /// <summary>
/// cache the parameters in the HashTable
/// </summary>
/// <param name="cacheKey">hashtable key name</param>
/// <param name="commandParameters">the parameters that need to cached</param>
public static void CacheParameters(string cacheKey, params MySqlParameter[] commandParameters)
{
parmCache[cacheKey] = commandParameters;
} /// <summary>
/// get parameters in hashtable by cacheKey
/// </summary>
/// <param name="cacheKey">hashtable key name</param>
/// <returns>the parameters</returns>
public static MySqlParameter[] GetCachedParameters(string cacheKey)
{
MySqlParameter[] cachedParms = (MySqlParameter[])parmCache[cacheKey]; if (cachedParms == null)
return null; MySqlParameter[] clonedParms = new MySqlParameter[cachedParms.Length]; for (int i = , j = cachedParms.Length; i < j; i++)
clonedParms[i] = (MySqlParameter)((ICloneable)cachedParms[i]).Clone(); return clonedParms;
} /// <summary>
///Prepare parameters for the implementation of the command
/// </summary>
/// <param name="cmd">mySqlCommand command</param>
/// <param name="conn">database connection that is existing</param>
/// <param name="trans">database transaction processing </param>
/// <param name="cmdType">SqlCommand command type (stored procedures, T-SQL statement, and so on.) </param>
/// <param name="cmdText">Command text, T-SQL statements such as Select * from Products</param>
/// <param name="cmdParms">return the command that has parameters</param>
private static void PrepareCommand(MySqlCommand cmd, MySqlConnection conn, MySqlTransaction trans, CommandType cmdType, string cmdText, MySqlParameter[] cmdParms)
{
if (conn.State != ConnectionState.Open)
conn.Open(); cmd.Connection = conn;
cmd.CommandText = cmdText; if (trans != null)
cmd.Transaction = trans; cmd.CommandType = cmdType; if (cmdParms != null)
foreach (MySqlParameter parm in cmdParms)
cmd.Parameters.Add(parm);
}
#region parameters
/// <summary>
/// Set parameters
/// </summary>
/// <param name="ParamName">parameter name</param>
/// <param name="DbType">data type</param>
/// <param name="Size">type size</param>
/// <param name="Direction">input or output</param>
/// <param name="Value">set the value</param>
/// <returns>Return parameters that has been assigned</returns>
public static MySqlParameter CreateParam(string ParamName, MySqlDbType DbType, Int32 Size, ParameterDirection Direction, object Value)
{
MySqlParameter param; if (Size > )
{
param = new MySqlParameter(ParamName, DbType, Size);
}
else
{ param = new MySqlParameter(ParamName, DbType);
} param.Direction = Direction;
if (!(Direction == ParameterDirection.Output && Value == null))
{
param.Value = Value;
} return param;
} /// <summary>
/// set Input parameters
/// </summary>
/// <param name="ParamName">parameter names, such as:@ id </param>
/// <param name="DbType">parameter types, such as: MySqlDbType.Int</param>
/// <param name="Size">size parameters, such as: the length of character type for the 100</param>
/// <param name="Value">parameter value to be assigned</param>
/// <returns>Parameters</returns>
public static MySqlParameter CreateInParam(string ParamName, MySqlDbType DbType, int Size, object Value)
{
return CreateParam(ParamName, DbType, Size, ParameterDirection.Input, Value);
} /// <summary>
/// Output parameters
/// </summary>
/// <param name="ParamName">parameter names, such as:@ id</param>
/// <param name="DbType">parameter types, such as: MySqlDbType.Int</param>
/// <param name="Size">size parameters, such as: the length of character type for the 100</param>
/// <param name="Value">parameter value to be assigned</param>
/// <returns>Parameters</returns>
public static MySqlParameter CreateOutParam(string ParamName, MySqlDbType DbType, int Size)
{
return CreateParam(ParamName, DbType, Size, ParameterDirection.Output, null);
} /// <summary>
/// Set return parameter value
/// </summary>
/// <param name="ParamName">parameter names, such as:@ id</param>
/// <param name="DbType">parameter types, such as: MySqlDbType.Int</param>
/// <param name="Size">size parameters, such as: the length of character type for the 100</param>
/// <param name="Value">parameter value to be assigned<</param>
/// <returns>Parameters</returns>
public static MySqlParameter CreateReturnParam(string ParamName, MySqlDbType DbType, int Size)
{
return CreateParam(ParamName, DbType, Size, ParameterDirection.ReturnValue, null);
} /// <summary>
/// Generate paging storedProcedure parameters
/// </summary>
/// <param name="CurrentIndex">CurrentPageIndex</param>
/// <param name="PageSize">pageSize</param>
/// <param name="WhereSql">query Condition</param>
/// <param name="TableName">tableName</param>
/// <param name="Columns">columns to query</param>
/// <param name="Sort">sort</param>
/// <returns>MySqlParameter collection</returns>
public static MySqlParameter[] GetPageParm(int CurrentIndex, int PageSize, string WhereSql, string TableName, string Columns, Hashtable Sort)
{
MySqlParameter[] parm = {
MySqlDBHelper.CreateInParam("@CurrentIndex", MySqlDbType.Int32, , CurrentIndex ),
MySqlDBHelper.CreateInParam("@PageSize", MySqlDbType.Int32, , PageSize ),
MySqlDBHelper.CreateInParam("@WhereSql", MySqlDbType.VarChar, , WhereSql ),
MySqlDBHelper.CreateInParam("@TableName", MySqlDbType.VarChar, , TableName ),
MySqlDBHelper.CreateInParam("@Column", MySqlDbType.VarChar, , Columns ),
MySqlDBHelper.CreateInParam("@Sort", MySqlDbType.VarChar, , GetSort(Sort) ),
MySqlDBHelper.CreateOutParam("@RecordCount", MySqlDbType.Int32, )
};
return parm;
}
/// <summary>
/// Statistics data that in table
/// </summary>
/// <param name="TableName">table name</param>
/// <param name="Columns">Statistics column</param>
/// <param name="WhereSql">conditions</param>
/// <returns>Set of parameters</returns>
public static MySqlParameter[] GetCountParm(string TableName, string Columns, string WhereSql)
{
MySqlParameter[] parm = {
MySqlDBHelper.CreateInParam("@TableName", MySqlDbType.VarChar, , TableName ),
MySqlDBHelper.CreateInParam("@CountColumn", MySqlDbType.VarChar, , Columns ),
MySqlDBHelper.CreateInParam("@WhereSql", MySqlDbType.VarChar, , WhereSql ),
MySqlDBHelper.CreateOutParam("@RecordCount", MySqlDbType.Int32, )
};
return parm;
}
/// <summary>
/// Get the sql that is Sorted
/// </summary>
/// <param name="sort"> sort column and values</param>
/// <returns>SQL sort string</returns>
private static string GetSort(Hashtable sort)
{
string str = "";
int i = ;
if (sort != null && sort.Count > )
{
foreach (DictionaryEntry de in sort)
{
i++;
str += de.Key + " " + de.Value;
if (i != sort.Count)
{
str += ",";
}
}
}
return str;
} /// <summary>
/// execute a trascation include one or more sql sentence(author:donne yin)
/// </summary>
/// <param name="connectionString"></param>
/// <param name="cmdType"></param>
/// <param name="cmdTexts"></param>
/// <param name="commandParameters"></param>
/// <returns>execute trascation result(success: true | fail: false)</returns>
public static bool ExecuteTransaction(string connectionString, CommandType cmdType, string[] cmdTexts, params MySqlParameter[][] commandParameters)
{
MySqlConnection myConnection = new MySqlConnection(connectionString); //get the connection object
myConnection.Open(); //open the connection
MySqlTransaction myTrans = myConnection.BeginTransaction(); //begin a trascation
MySqlCommand cmd = new MySqlCommand();
cmd.Connection = myConnection;
cmd.Transaction = myTrans; try
{
for (int i = ; i < cmdTexts.Length; i++)
{
PrepareCommand(cmd, myConnection, null, cmdType, cmdTexts[i], commandParameters[i]);
cmd.ExecuteNonQuery();
cmd.Parameters.Clear();
}
myTrans.Commit();
}
catch
{
myTrans.Rollback();
return false;
}
finally
{
myConnection.Close();
}
return true;
}
#endregion /// <summary>
/// 分页获得数据
/// </summary>
/// <param name="PageIndex">页码</param>
/// <param name="PageSize">每页显示数据量</param>
/// <param name="TableName">表名,可以是自定义查询集合</param>
/// <param name="_Where">条件语句,需要以where开头</param>
/// <param name="OrderStr">排序语句</param>
/// <param name="RecordCount">记录数 输出参数</param>
/// <param name="PageCount">总页数 输出参数</param>
/// <returns></returns>
public static DataTable GetDataTableByPage(string connectionString, int PageIndex, int PageSize, string TableName, string _Where, string OrderStr, out int RecordCount, out int PageCount)
{
string selectText = @"SELECT * FROM " + TableName + " " + _Where + " " + OrderStr + " LIMIT " + ((PageIndex - ) * PageSize).ToString() + "," + PageSize.ToString();
string countText = @"SELECT count(*) FROM " + TableName + " " + _Where; DataSet retSet = new DataSet();
using (MySqlDataAdapter msda = new MySqlDataAdapter(selectText, connectionString))
{
msda.Fill(retSet);
}
object objCount = ExecuteScalar(connectionString, CommandType.Text, countText, null); RecordCount = ;
PageCount = ;
if (objCount != null && objCount != DBNull.Value)
{
RecordCount = Convert.ToInt32(objCount);
PageCount = (RecordCount / PageSize) + ((RecordCount % PageSize) > ? : );
}
if (retSet != null && retSet.Tables.Count > )
{
return retSet.Tables[];
}
return null;
}
/// <summary>
/// 分页获得数据
/// </summary>
/// <param name="PageIndex">页码</param>
/// <param name="PageSize">每页显示数据量</param>
/// <param name="TableName">表名,可以是自定义查询集合</param>
/// <param name="Fields">字段名</param>
/// <param name="_Where">条件语句,需要以where开头</param>
/// <param name="OrderStr">排序语句</param>
/// <param name="RecordCount">记录数 输出参数</param>
/// <param name="PageCount">总页数 输出参数</param>
/// <returns></returns>
public static DataTable GetDataTableByPage(string connectionString, int PageIndex, int PageSize, string TableName, string Fields, string _Where, string OrderStr, out int RecordCount, out int PageCount)
{
string selectText = @"SELECT " + Fields + " FROM " + TableName + " " + _Where + " " + OrderStr + " LIMIT " + ((PageIndex - ) * PageSize).ToString() + "," + PageSize.ToString();
string countText = @"SELECT COUNT(*) FROM " + TableName + " " + _Where; DataSet retSet = new DataSet();
using (MySqlDataAdapter msda = new MySqlDataAdapter(selectText, connectionString))
{
msda.Fill(retSet);
}
object objCount = ExecuteScalar(connectionString, CommandType.Text, countText, null); RecordCount = ;
PageCount = ;
if (objCount != null && objCount != DBNull.Value)
{
RecordCount = Convert.ToInt32(objCount);
PageCount = (RecordCount / PageSize) + ((RecordCount % PageSize) > ? : );
}
if (retSet != null && retSet.Tables.Count > )
{
return retSet.Tables[];
}
return null;
} /// <summary>
/// 分页获得数据
/// </summary>
/// <param name="PageIndex">页码</param>
/// <param name="PageSize">每页显示数据量</param>
/// <param name="TableName">表名,可以是自定义查询集合</param>
/// <param name="Fields">字段名</param>
/// <param name="_Where">条件语句,需要以where开头</param>
/// <param name="OrderStr">排序语句</param>
/// <param name="RecordCount">记录数 输出参数</param>
/// <param name="PageCount">总页数 输出参数</param>
/// <returns></returns>
public static DataTable GetDataTableByPage(string connectionString, int PageIndex, int PageSize, string TableName, string Fields, string _Where, string OrderStr, out int RecordCount, out int PageCount, params MySqlParameter[] commandParameters)
{
string selectText = @"SELECT " + Fields + " FROM " + TableName + " " + _Where + " " + OrderStr + " LIMIT " + ((PageIndex - ) * PageSize).ToString() + "," + PageSize.ToString();
string countText = @"SELECT COUNT(*) FROM " + TableName + " " + _Where; DataSet retSet = new DataSet();
MySqlCommand cmd = new MySqlCommand();
using (MySqlConnection connection = new MySqlConnection(connectionString))
{
PrepareCommand(cmd, connection, null, CommandType.Text, selectText, commandParameters);
using (MySqlDataAdapter msda = new MySqlDataAdapter(cmd))
{
msda.Fill(retSet);
}
} object objCount = ExecuteScalar(connectionString, CommandType.Text, countText, commandParameters); RecordCount = ;
PageCount = ;
if (objCount != null && objCount != DBNull.Value)
{
RecordCount = Convert.ToInt32(objCount);
PageCount = (RecordCount / PageSize) + ((RecordCount % PageSize) > ? : );
}
if (retSet != null && retSet.Tables.Count > )
{
return retSet.Tables[];
}
return null;
}
}
}

需要下载一个MySql.Data.dll文件

连接字符串格式:<add name="MySQLConnString" connectionString="server=******; user id=******j; password=******; database=******"/>

注意:connectionString 不是 Data Source了,是server。

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