ASP.NET中SQL Server数据库访问通用类(7)

    /// 执行一个查询，并返回结果集
    /// </summary>
    /// <param name="sql">要查询的SQL文本命令</param>
    /// <param name="commandType">查询语句类型，存储过程或SQL文本命令</param>
    /// <returns>查询结果集</returns>
    public DataTable ExecuteDataTable(string sql, CommandType commandType)
    {
        return ExecuteDataTable(sql, commandType, null);
    }

    /// <summary>
    /// 执行一个查询，并返回结果集
    /// </summary>
    /// <param name="sql">要查询的SQL文本命令</param>
    /// <param name="commandType">查询语句类型，存储过程或SQL文本命令</param>
    /// <param name="parameters">T-SQL语句或存储过程的参数组</param>
    /// <returns>查询结果集</returns>
    public DataTable ExecuteDataTable(string sql, CommandType commandType, SqlParameter[] parameters)
    {
        //实例化DataTable，用于装载查询结果集
        DataTable data = new DataTable();
        using (SqlConnection connection = new SqlConnection(connectionString))
        {
            using (SqlCommand command = new SqlCommand(sql, connection))
            {
                //指定CommandType
                command.CommandType = commandType;
                if (parameters != null)
                {
                    foreach (SqlParameter parameter in parameters)
                    {
                        command.Parameters.Add(parameter);
                    }
                }
                //实例化SqlDataAdapter