• sqlHelper


    /// <summary>
    /// The SqlHelper class is intended to encapsulate high performance,
    /// scalable best practices for Tools uses of SqlClient.
    /// </summary>
    public abstract class SqlHelper
    {

    //Database connection strings
    //public static readonly string DbIP = ConfigurationManager.AppSettings["ServerIP"];
    //public static readonly string DbName = ConfigurationManager.AppSettings["DbName"];
    //public static readonly string DbString = "Data Source={0};Initial Catalog={1};Persist Security Info=True;User ID=sa;PASSWORD=sa2005;";
    //public static string ConnectionString = string.Empty;
    //public static string ConnectionString = ConfigurationManager.ConnectionStrings["SqlConnString"].ConnectionString;

    public static string ConnectionString = ConfigurationManager.ConnectionStrings["DefaultConnection"].ConnectionString;
    // Hashtable to store cached parameters
    private static Hashtable parmCache = Hashtable.Synchronized(new Hashtable());

    /// <summary>
    /// Execute a SqlCommand (that returns no resultset) against the database specified in the connection string
    /// using the provided parameters.
    /// </summary>
    /// <remarks>
    /// e.g.:
    /// int result = ExecuteNonQuery(connString, CommandType.StoredProcedure, "PublishOrders", new SqlParameter("@prodid", 24));
    /// </remarks>
    /// <param name="connectionString">a valid connection string for a SqlConnection</param>
    /// <param name="commandType">the CommandType (stored procedure, text, etc.)</param>
    /// <param name="commandText">the stored procedure name or T-SQL command</param>
    /// <param name="commandParameters">an array of SqlParamters used to execute the command</param>
    /// <returns>an int representing the number of rows affected by the command</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>
    /// Execute a SqlCommand (that returns no resultset) against an existing database connection
    /// using the provided parameters.
    /// </summary>
    /// <remarks>
    /// e.g.:
    /// int result = ExecuteNonQuery(connString, CommandType.StoredProcedure, "PublishOrders", new SqlParameter("@prodid", 24));
    /// </remarks>
    /// <param name="conn">an existing database connection</param>
    /// <param name="commandType">the CommandType (stored procedure, text, etc.)</param>
    /// <param name="commandText">the stored procedure name or T-SQL command</param>
    /// <param name="commandParameters">an array of SqlParamters used to execute the command</param>
    /// <returns>an int representing the number of rows affected by the command</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>
    /// Execute a SqlCommand (that returns no resultset) using an existing SQL Transaction
    /// using the provided parameters.
    /// </summary>
    /// <remarks>
    /// e.g.:
    /// int result = ExecuteNonQuery(connString, CommandType.StoredProcedure, "PublishOrders", new SqlParameter("@prodid", 24));
    /// </remarks>
    /// <param name="trans">an existing sql transaction</param>
    /// <param name="commandType">the CommandType (stored procedure, text, etc.)</param>
    /// <param name="commandText">the stored procedure name or T-SQL command</param>
    /// <param name="commandParameters">an array of SqlParamters used to execute the command</param>
    /// <returns>an int representing the number of rows affected by the command</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;
    }

    /// <summary>
    /// Execute a SqlCommand that returns a resultset against the database specified in the connection string
    /// using the provided parameters.
    /// </summary>
    /// <remarks>
    /// e.g.:
    /// SqlDataReader r = ExecuteReader(connString, CommandType.StoredProcedure, "PublishOrders", new SqlParameter("@prodid", 24));
    /// </remarks>
    /// <param name="connectionString">a valid connection string for a SqlConnection</param>
    /// <param name="commandType">the CommandType (stored procedure, text, etc.)</param>
    /// <param name="commandText">the stored procedure name or T-SQL command</param>
    /// <param name="commandParameters">an array of SqlParamters used to execute the command</param>
    /// <returns>A SqlDataReader containing the results</returns>
    public static SqlDataReader ExecuteReader(string connectionString, CommandType cmdType, string cmdText, params SqlParameter[] commandParameters)
    {
    SqlCommand cmd = new SqlCommand();
    SqlConnection conn = new SqlConnection(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);
    SqlDataReader rdr = cmd.ExecuteReader(CommandBehavior.CloseConnection);
    cmd.Parameters.Clear();
    return rdr;
    }
    catch
    {
    conn.Close();
    throw;
    }
    }

    /// <summary>
    /// Execute a SqlCommand that returns the first column of the first record against the database specified in the connection string
    /// using the provided parameters.
    /// </summary>
    /// <remarks>
    /// e.g.:
    /// Object obj = ExecuteScalar(connString, CommandType.StoredProcedure, "PublishOrders", new SqlParameter("@prodid", 24));
    /// </remarks>
    /// <param name="connectionString">a valid connection string for a SqlConnection</param>
    /// <param name="commandType">the CommandType (stored procedure, text, etc.)</param>
    /// <param name="commandText">the stored procedure name or T-SQL command</param>
    /// <param name="commandParameters">an array of SqlParamters used to execute the command</param>
    /// <returns>An object that should be converted to the expected type using Convert.To{Type}</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>
    /// Execute a SqlCommand that returns the first column of the first record against an existing database connection
    /// using the provided parameters.
    /// </summary>
    /// <remarks>
    /// e.g.:
    /// Object obj = ExecuteScalar(connString, CommandType.StoredProcedure, "PublishOrders", new SqlParameter("@prodid", 24));
    /// </remarks>
    /// <param name="conn">an existing database connection</param>
    /// <param name="commandType">the CommandType (stored procedure, text, etc.)</param>
    /// <param name="commandText">the stored procedure name or T-SQL command</param>
    /// <param name="commandParameters">an array of SqlParamters used to execute the command</param>
    /// <returns>An object that should be converted to the expected type using Convert.To{Type}</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;
    }

    /// <summary>
    /// add parameter array to the cache
    /// </summary>
    /// <param name="cacheKey">Key to the parameter cache</param>
    /// <param name="cmdParms">an array of SqlParamters to be cached</param>
    public static void CacheParameters(string cacheKey, params SqlParameter[] commandParameters)
    {
    parmCache[cacheKey] = commandParameters;
    }

    /// <summary>
    /// Retrieve cached parameters
    /// </summary>
    /// <param name="cacheKey">key used to lookup parameters</param>
    /// <returns>Cached SqlParamters array</returns>
    public static SqlParameter[] GetCachedParameters(string cacheKey)
    {
    SqlParameter[] cachedParms = (SqlParameter[])parmCache[cacheKey];

    if (cachedParms == null)
    return null;

    SqlParameter[] clonedParms = new SqlParameter[cachedParms.Length];

    for (int i = 0, j = cachedParms.Length; i < j; i++)
    clonedParms[i] = (SqlParameter)((ICloneable)cachedParms[i]).Clone();

    return clonedParms;
    }

    /// <summary>
    /// Prepare a command for execution
    /// </summary>
    /// <param name="cmd">SqlCommand object</param>
    /// <param name="conn">SqlConnection object</param>
    /// <param name="trans">SqlTransaction object</param>
    /// <param name="cmdType">Cmd type e.g. stored procedure or text</param>
    /// <param name="cmdText">Command text, e.g. Select * from Products</param>
    /// <param name="cmdParms">SqlParameters to use in the command</param>
    private static void PrepareCommand(SqlCommand cmd, SqlConnection conn, SqlTransaction trans, CommandType cmdType, string cmdText, SqlParameter[] 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 (SqlParameter parm in cmdParms)
    cmd.Parameters.Add(parm);
    }
    }


    /// <summary>
    /// Query data from Procedure
    /// </summary>
    /// <param name="cmdText">Procedure name</param>
    /// <param name="paramName">Param name</param>
    /// <param name="paramValue">Param value</param>
    /// <returns>DataView</returns>
    public static DataTable ExecuteProceDataTable(string connectionString, CommandType cmdType, string cmdText, params SqlParameter[] commandParameters)
    {
    DataTable dt = new DataTable();

    // Create a new Sql command
    SqlCommand cmd = new SqlCommand();

    //Create a connection
    using (SqlConnection connection = new SqlConnection(connectionString))
    {
    //Open the connection if required
    if (connection.State != ConnectionState.Open)
    connection.Open();

    cmd.Connection = connection;
    cmd.CommandType = cmdType;
    cmd.CommandText = cmdText;

    if (commandParameters != null)
    {
    foreach (SqlParameter param in commandParameters)
    {
    cmd.Parameters.Add(param);
    }
    }

    SqlDataAdapter adr = new SqlDataAdapter(cmd);

    try
    {
    adr.Fill(dt);
    }
    catch
    { }

    return dt;

    }

    }

    #region ExecuteDataSet

    /// <summary>
    /// Execute a SqlCommand (that returns a resultset and takes no parameters) against the database specified in
    /// the connection string.
    /// </summary>
    /// <remarks>
    /// e.g.:
    /// DataSet ds = ExecuteDataset(connString, CommandType.StoredProcedure, "GetOrders");
    /// </remarks>
    public static DataSet ExecuteDataset(string connectionString, CommandType commandType, string commandText)
    {
    //pass through the call providing null for the set of SqlParameters
    return ExecuteDataset(connectionString, commandType, commandText, (SqlParameter[])null);
    }


    /// <summary>
    /// Execute a SqlCommand (that returns a resultset) against the database specified in the connection string
    /// using the provided parameters.
    /// </summary>
    /// <remarks>
    /// e.g.:
    /// DataSet ds = ExecuteDataset(connString, CommandType.StoredProcedure, "GetOrders", new SqlParameter("@prodid", 24));
    /// </remarks>
    /// <param name="connectionString">a valid connection string for a SqlConnection</param>
    /// <param name="commandType">the CommandType (stored procedure, text, etc.)</param>
    /// <param name="commandText">the stored procedure name or PL/SQL command</param>
    /// <param name="commandParameters">an array of SqlParamters used to execute the command</param>
    /// <returns>a dataset containing the resultset generated by the command</returns>
    public static DataSet ExecuteDataset(string connectionString, CommandType commandType, string commandText, params SqlParameter[] commandParameters)
    {
    //create & open a SqlConnection, and dispose of it after we are done.
    using (SqlConnection cn = new SqlConnection(connectionString))
    {
    cn.Open();

    //call the overload that takes a connection in place of the connection string
    return ExecuteDataset(cn, commandType, commandText, commandParameters);
    }
    }

    /// <summary>
    /// Execute a SqlCommand (that returns a resultset and takes no parameters) against the provided SqlConnection.
    /// </summary>
    /// <remarks>
    /// e.g.:
    /// DataSet ds = ExecuteDataset(conn, CommandType.StoredProcedure, "GetOrders");
    /// </remarks>
    /// <param name="connection">a valid SqlConnection</param>
    /// <param name="commandType">the CommandType (stored procedure, text, etc.)</param>
    /// <param name="commandText">the stored procedure name or PL/SQL command</param>
    /// <returns>a dataset containing the resultset generated by the command</returns>
    public static DataSet ExecuteDataset(SqlConnection connection, CommandType commandType, string commandText)
    {
    //pass through the call providing null for the set of SqlParameters
    return ExecuteDataset(connection, commandType, commandText, (SqlParameter[])null);
    }

    /// <summary>
    /// Execute a SqlCommand (that returns a resultset and takes no parameters) against the provided SqlTransaction.
    /// </summary>
    /// <remarks>
    /// e.g.:
    /// DataSet ds = ExecuteDataset(trans, CommandType.StoredProcedure, "GetOrders");
    /// </remarks>
    /// <param name="transaction">a valid SqlTransaction</param>
    /// <param name="commandType">the CommandType (stored procedure, text, etc.)</param>
    /// <param name="commandText">the stored procedure name or PL/SQL command</param>
    /// <returns>a dataset containing the resultset generated by the command</returns>
    public static DataSet ExecuteDataset(SqlTransaction transaction, CommandType commandType, string commandText)
    {
    //pass through the call providing null for the set of SqlParameters
    return ExecuteDataset(transaction, commandType, commandText, (SqlParameter[])null);
    }


    /// <summary>
    /// Execute a SqlCommand (that returns a resultset) against the specified SqlConnection
    /// using the provided parameters.
    /// </summary>
    /// <remarks>
    /// e.g.:
    /// DataSet ds = ExecuteDataset(conn, CommandType.StoredProcedure, "GetOrders", new SqlParameter("@prodid", 24));
    /// </remarks>
    /// <param name="connection">a valid SqlConnection</param>
    /// <param name="commandType">the CommandType (stored procedure, text, etc.)</param>
    /// <param name="commandText">the stored procedure name or PL/SQL command</param>
    /// <param name="commandParameters">an array of SqlParamters used to execute the command</param>
    /// <returns>a dataset containing the resultset generated by the command</returns>
    public static DataSet ExecuteDataset(SqlConnection connection, CommandType commandType, string commandText, params SqlParameter[] commandParameters)
    {
    //create a command and prepare it for execution
    SqlCommand cmd = new SqlCommand();
    PrepareCommand(cmd, connection, (SqlTransaction)null, commandType, commandText, commandParameters);

    //create the DataAdapter & DataSet
    SqlDataAdapter da = new SqlDataAdapter(cmd);
    DataSet ds = new DataSet();

    //fill the DataSet using default values for DataTable names, etc.
    da.Fill(ds);

    // detach the SqlParameters from the command object, so they can be used again.
    cmd.Parameters.Clear();

    //return the dataset
    return ds;
    }


    /// <summary>
    /// Execute a SqlCommand (that returns a resultset) against the specified SqlTransaction
    /// using the provided parameters.
    /// </summary>
    /// <remarks>
    /// e.g.:
    /// DataSet ds = ExecuteDataset(trans, CommandType.StoredProcedure, "GetOrders", new SqlParameter("@prodid", 24));
    /// </remarks>
    /// <param name="transaction">a valid SqlTransaction</param>
    /// <param name="commandType">the CommandType (stored procedure, text, etc.)</param>
    /// <param name="commandText">the stored procedure name or PL/SQL command</param>
    /// <param name="commandParameters">an array of SqlParamters used to execute the command</param>
    /// <returns>a dataset containing the resultset generated by the command</returns>
    ///
    public static DataSet ExecuteDataset(SqlTransaction transaction, CommandType commandType, string commandText, params SqlParameter[] commandParameters)
    {
    //create a command and prepare it for execution
    SqlCommand cmd = new SqlCommand();
    PrepareCommand(cmd, transaction.Connection, transaction, commandType, commandText, commandParameters);

    //create the DataAdapter & DataSet
    SqlDataAdapter da = new SqlDataAdapter(cmd);
    DataSet ds = new DataSet();

    //fill the DataSet using default values for DataTable names, etc.
    da.Fill(ds);

    // detach the SqlParameters from the command object, so they can be used again.
    cmd.Parameters.Clear();

    //return the dataset
    return ds;
    }

    /// <summary>
    /// DataSet操作範例
    /// </summary>
    /// <param name="connectionString"></param>
    /// <param name="SQLString"></param>
    /// <returns></returns>
    public static DataSet Query(string connectionString, string SQLString)
    {
    using (SqlConnection connection = new SqlConnection(connectionString))
    {
    DataSet ds = new DataSet();
    try
    {
    connection.Open();
    SqlDataAdapter command = new SqlDataAdapter(SQLString, connection);
    command.Fill(ds, "ds");
    }
    catch (System.Data.SqlClient.SqlException ex)
    {
    throw new Exception(ex.Message);
    }
    finally
    {
    connection.Close();
    }
    return ds;
    }
    }


    #endregion ExecuteDataSet
    }

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  • 原文地址:https://www.cnblogs.com/zhang102137/p/8572793.html
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