C#

Member 10564850 wrote:

My query can't executed successfully please help ??

OriginalGriff wrote:[^]

Just remember in future - the better the info you give us, the quicker we can give you a solution!

string s = "INSERT INTO [Students Records] (Name, Age, Class, Gender, [Guardian's Name], [Contact.No], Address, [Email-Address]) VALUES(@Name, @Age, @Class, @Gender, @GuardiansName, @ContactNo, @Address, @EmailAddress)";

Name, Age, Class, Gender, GuardianName, ContactPhone, Address, EmailAddress

Dim databaseUtcTime = dateTimeFromDatabase

' Make sure the DateTime returned by the database is in UTC.
databaseUtcTime = databaseUtcTime.SpecifyKind(DateTimeKind.Utc)

' Dump the current time...
Debug.WriteLine(String.Format("UtcTime:   {0}", databaseUtcTime.ToString()))
Debug.WriteLine(String.Format("LocalTime: {0}", databaseUtcTime.ToLocalTime().ToString()))

Marco Bertschi wrote:

since System.DateTime's ParseExact method tends to have problems dealing with a variable amount of microseconds, and does not provide any field to store the UTC Offset.

V. wrote:

Variable microseconds can be handled with a few lines of business logic I think

V. wrote:

for the UTC Offset you could create a new DateTime Object that inherits from the DateTime class? (just a quick thought)

Marco Bertschi wrote:

Can I achieve the same with System.DateTime?

using System;

namespace Feb4_2014_InheritFromTupleT1T2T3
{
    public class DateTimeEx: Tuple<DateTime, long, Int32>
    {
        private const string msPrefix = ":Z";
        private const string tzPlus = "+";

        private string tzPre;

        public DateTime dateTime { set; get; }

        public long milliSeconds { set; get; }

        public Int32 utcOffset { set; get; }

        public DateTimeEx(DateTime datetime, long millisec, Int32 utcoff) : base(datetime, millisec, utcoff)
        {
            dateTime = datetime;
            milliSeconds = millisec;
            utcOffset = utcoff;
        }

        public override string ToString()
        {
            tzPre = (milliSeconds < 0) ? "" : tzPlus;

            return string.Format("{0}-{1}-{2}T{3}:{4}:{5}.{6}Z{7}{8}", Item1.Year, Item1.Month, Item1.Day, Item1.Hour, Item1.Minute, Item1.Second, milliSeconds, tzPre, utcOffset);
        }
    }
}

DateTime rightNow = DateTime.Now;

DateTimeEx dEx1 = new DateTimeEx(rightNow, 0, 7);
DateTimeEx dEx2 = new DateTimeEx(rightNow, 0, 7);
DateTimeEx dEx3 = new DateTimeEx(rightNow, 230, 4);

Console.WriteLine(dEx1); // => 2014-2-4T21:35:19.0Z+7
Console.WriteLine(dEx3); // => 2014-2-4T21:38:1.230Z+4

Console.WriteLine(dEx1.Equals(dEx2)); // => true
Console.WriteLine(dEx1.Equals(dEx3)); // => false

BillWoodruff wrote:

Based on the observation that all of your Properties, except milliseconds, are 'get only, I would say "yes," if you were willing to accept the limitations of inheriting from a data-structure like a Tuple<T1,T2,T3> ... given the fact that Tuple instances are immutable.

BillWoodruff wrote:

would hope what you would get from this is being able to use Parse, and ParseExact on the DateTime component,

Marco Bertschi wrote:

What I have done so far is that I consider System.DateTime being unuseable as timestamp,

jschell wrote:

On the C# (application side) the input/output is a DateTime.

jschell wrote:

On the syslog interface side it is a string.

Quote:

TIMESTAMP = NILVALUE / FULL-DATE "T" FULL-TIME
FULL-DATE = DATE-FULLYEAR "-" DATE-MONTH "-" DATE-MDAY
DATE-FULLYEAR = 4DIGIT
DATE-MONTH = 2DIGIT ; 01-12
DATE-MDAY = 2DIGIT ; 01-28, 01-29, 01-30, 01-31 based on
; month/year
FULL-TIME = PARTIAL-TIME TIME-OFFSET
PARTIAL-TIME = TIME-HOUR ":" TIME-MINUTE ":" TIME-SECOND
[TIME-SECFRAC]
TIME-HOUR = 2DIGIT ; 00-23
TIME-MINUTE = 2DIGIT ; 00-59
TIME-SECOND = 2DIGIT ; 00-59
TIME-SECFRAC = "." 1*6DIGIT
TIME-OFFSET = "Z" / TIME-NUMOFFSET
TIME-NUMOFFSET = ("+" / "-") TIME-HOUR ":" TIME-MINUTE

TnTinMn wrote:

In your lounge post[^] you say that you imposing RFC5424[^] as the criteria. Based on the following format that I found online, you will not be able to properly store a RFC5424 timestamp in a DateTime structure due to the possibility of the TIME-SECFRAC being allowed to have up six digits. The DateTime structure can only accommodate milliseconds (3 digits).

TnTinMn wrote:

You also have shown TimeStamp examples[^] that you say are valid. However these have decimal TIME-NUMOFFSET values instead of "Hours:Minutes"; again this conflicts with the specification. Is it your intent to allow these deviations?

TnTinMn wrote:

Just courious, is there a reason that you have implemented your own GetDayMaxDaysOfMonth and Is LeapYear versus using those from the DateTimeStructure (DateTime.DaysInMonth[^], DateTime.IsLeapYear[^])?

TnTinMn wrote:

You could use DateTime.TryParseExact with this format string: "yyyy-MM-dd\THH:mm:ss"

If that succeeds then, then you would need to extract the fractional second component (if it exists) as microseconds (upto 6 digits) and convert the microseconds to Ticks. Then you you can use the DateTime.AddTicks method on the DateTime value returned from the TryParseExact method.

TnTinMn wrote:

I have put together a class to parse a TimeStamp string using this methodolgy and can make a copy of the code available if you are interested in it.

using System;
using System.Collections.Generic;
using System.Globalization;
using System.Linq;
using System.Text;
using System.Text.RegularExpressions;

namespace Springlog.Com.Messaging
{
    /// <summary>
    /// Represents the Timestamp of a <see cref="SyslogMessageHeader"/>
    /// Author: Marco Bertschi, (C) 2014 Marco Bertschi
    /// </summary>
    public class SyslogTimestamp
    {
        #region Properties
        /// <summary>
        /// Returns the count of the days for a specific month in a specific year.
        /// </summary>
        /// <param name="month">month  </param>
        /// <param name="year">year</param>
        /// <returns></returns>
        static short GetDayMaxDaysOfMonth(int month, int year)
        {
            if (month != 2)
            {
                //  January       March         May           July          August        October        December
                if (month == 1 || month == 3 || month == 5 || month == 7 || month == 8 || month == 10 || month == 12)
                {
                    return 31;
                }
                else // April, June, September, November
                {
                    return 30;
                }
            }
            else //February
            {
                if (IsLeapYear(year))
                {
                    return 29;
                }
                return 28;
            }
        }
        /// <summary>
        /// Returns true if the argument is a leap year
        /// </summary>
        /// <param name="year">The year number to check</param>
        /// <returns></returns>
        private static bool IsLeapYear(int year)
        {
            if (year % 4 == 0)
            {
                if (year % 100 == 0)
                {
                    if (year % 400 == 0)
                    {
                        return true;
                    }
                    return false;
                }
                return true;
            }
            return false;
        }

        /// <summary>
        /// The part of the Timestamp which represents the year.
        /// </summary>
        int year;
        /// <summary>
        /// Gets the year part of the Timestamp.
        /// </summary>
        public int Year
        {
            get { return year; }
        }
        /// <summary>
        /// The part of the Timestamp which represents the month.
        /// </summary>
        int month;
        /// <summary>
        /// Gets the month part of the Timestamp.
        /// </summary>
        public int Month
        {
            get { return month; }
        }
        /// <summary>
        /// The part of the Timestamp which represents the day of the month.
        /// </summary>
        int dayOfMonth;
        /// <summary>
        /// Gets the days part of the Timestamp.
        /// </summary>
        public int DayOfMonth
        {
            get { return dayOfMonth; }
        }
        /// <summary>
        /// The part of the Timestamp which represents the hours.
        /// </summary>
        int hours;
        /// <summary>
        /// Gets the hours part of the Timestamp.
        /// </summary>
        public int Hours
        {
            get { return hours; }
        }
        /// <summary>
        /// The part of the Timestamp which represents the minutes.
        /// </summary>
        int minutes;
        /// <summary>
        /// Gets the minutes part of the Timestamp.
        /// </summary>
        public int Minutes
        {
            get { return minutes; }
        }
        /// <summary>
        /// The part of the Timestamp which represents the seconds.
        /// </summary>
        int seconds;
        /// <summary>
        /// Gets the seconds part of the Timestamp.
        /// </summary>
        public int Seconds
        {
            get { return seconds; }
        }
        /// <summary>
        /// The part of the Timestamp which represents the year.
        /// </summary>
        int miliseconds;
        /// <summary>
        /// Gets the milliseconds part of the Timestamp.
        /// </summary>
        public int Miliseconds
        {
            get { return miliseconds; }
        }
        /// <summary>
        /// The offset from the UTC timezone
        /// </summary>
        double utcOffset;
        /// <summary>
        /// Gets or sets the offset from the UTC timezone.
        /// </summary>
        public double UtcOffset
        {
            get { return utcOffset; }
            set { utcOffset = value; }
        }
        #endregion

        public SyslogTimestamp()
        {
            Reset();
        }

        public SyslogTimestamp(string timestamp)
        {
            Reset();
            FromString(timestamp);
        }

        public SyslogTimestamp(DateTime timestamp)
        {
            Reset();
            FromDateTime(timestamp);
        }

        /// <summary>
        /// Resets all fields to their default values;
        /// </summary>
        private void Reset()
        {
            miliseconds = 0;
            seconds = 0;
            minutes = 0;
            hours = 0;
            dayOfMonth = 0;
            month = 0;
            year = 0;
            utcOffset = 0;
        }

        /// <summary>
        /// Parses a string into a Syslog timestamp.
        /// </summary>
        /// <param name="dateTime">string which is going to be parsed</param>
        /// <returns>true = success | false = invalid string</returns>
        public bool FromString(string dateTime)
        {
            Reset();// All fields must be resetted - Otherwise the parsing will give a wrong value!
            Regex splitRegex = new Regex(@"(\d{4})-(0?[1-9]|1[0-2])-([0-2]?\d|3[0-1])T?([0-1]?\d|2[0-3]):([0-5]?\d):([0-5]?\d)\.?(\d{0,6})?Z?([+-]?\d\.?\d?|\d{2}?|[0]?1[0-2]\.?\d?|\d{2}?)?", RegexOptions.IgnoreCase);
            Match timestamp = splitRegex.Match(dateTime);

            if (timestamp.Groups.Count == 9)
            {
                AddYears(Int32.Parse(timestamp.Groups[1].Value));
                AddMonths(Int32.Parse(timestamp.Groups[2].Value));
                AddDays(Int32.Parse(timestamp.Groups[3].Value));
                AddHours(Int32.Parse(timestamp.Groups[4].Value));
                AddMinutes(Int32.Parse(timestamp.Groups[5].Value));
                AddSeconds(Int32.Parse(timestamp.Groups[6].Value));
                if (!string.IsNullOrWhiteSpace(timestamp.Groups[7].Value))
                {
                    AddMilliseconds(Int32.Parse(timestamp.Groups[7].Value));
                }
                if (!string.IsNullOrWhiteSpace(timestamp.Groups[8].Value))
                {
                    utcOffset = Double.Parse(timestamp.Groups[8].Value, CultureInfo.InvariantCulture);
                }
                return true;
            }
            else
            {
                return false;
            }
        }
        /// <summary>
        /// Returns a fully formatted Syslog timestamp, as string.
        /// </summary>
        /// <returns>Syslog timestamp, as string</returns>
        public string ToFormattedString()
        {
            string timezonePreSign = "Z";
            if (utcOffset < 0)
            {
                timezonePreSign = "";
            }
            return string.Format("{0}-{1}-{2}T{3}:{4}:{5}.{6}{7}{8}", year, month, dayOfMonth, hours, minutes, seconds, miliseconds, timezonePreSign, utcOffset.ToString().Replace(',','.'));
        }

        public DateTime ToDateTime()
        {
            DateTimeKind dateTimeKind;
            if(utcOffset == 0)
            {
                dateTimeKind = DateTimeKind.Utc;
            }
            else
            {
                dateTimeKind = DateTimeKind.Local;
            }
            return new DateTime(year, month, dayOfMonth, hours, minutes, seconds, miliseconds, dateTimeKind);
        }

        /// <summary>
        /// Overriden ToString() method - Displays the same as ToFormattedString().
        /// </summary>
        /// <returns></returns>
        public override string ToString()
        {
            return this.ToFormattedString();
        }
        /// <summary>
        /// Parses a <see cref="System.DateTime"/> type to a <see cref="SyslogTimestamp"/>. It is assumed that the
        /// DateTime type must be converted to UTC if the second argument is left out.
        /// </summary>
        /// <remarks>
        /// The FromDateTime method recognizes only the current daylight saving time adjustment rule for the local time zone.
        /// As a result, it is guaranteed to accurately return the UTC offset of a local time only during the period in which the
        /// latest adjustment rule is in effect. It may return inaccurate results if time is a historic date and time value
        /// that was subject to a previous adjustment rule.
        /// </remarks>
        /// <param name="timestamp">The <see cref="System.DateTime"/> type which will be parsed</param>
        public void FromDateTime(DateTime timestamp)
        {
            TimeSpan utcOffset = TimeZone.CurrentTimeZone.GetUtcOffset(timestamp);
            this.utcOffset = utcOffset.Hours + (utcOffset.Minutes / 100);

            AddMilliseconds(timestamp.Millisecond);
            AddSeconds(timestamp.Second);
            AddMinutes(timestamp.Minute);
            AddHours(timestamp.Hour);
            AddDays(timestamp.Day);
            AddMonths(timestamp.Month);
            AddYears(timestamp.Year);
        }

        /// <summary>
        /// Adds a <see cref="System.TimeSpan"/> to the timestamp
        /// </summary>
        /// <param name="timeSpan">The time span which is added to the Timestamp</param>
        public void Add(TimeSpan timeSpan)
        {
            AddMilliseconds(timeSpan.Milliseconds);
            AddSeconds(timeSpan.Seconds);
            AddMinutes(timeSpan.Minutes);
            AddHours(timeSpan.Hours);
            AddDays(timeSpan.Days);
        }
        /// <summary>
        /// Adds the passed millisecond value to the timestamp
        /// </summary>
        /// <param name="val">Added milliseconds</param>
        public void AddMilliseconds(int val)
        {
            if (val + miliseconds >= 1000)
            {
                AddSeconds( val / 1000);
                miliseconds = (val % 1000);
            }
            else
            {
                miliseconds += val;
            }
        }
        /// <summary>
        /// Adds the passed second value to the timestamp
        /// </summary>
        /// <param name="val">Added seconds</param>
        private void AddSeconds(int val)
        {
            if (seconds + val >= 60)
            {
                AddMinutes(val / 60);
                seconds = (val % 60);
            }
            else
            {
                seconds += val;
            }
        }
        /// <summary>
        /// Adds the passed minute value to the timestamp
        /// </summary>
        /// <param name="val">Added minutes</param>
        private void AddMinutes(int val)
        {
            if (minutes + val >= 60)
            {
                AddMinutes(val / 60);
                minutes = (val % 60);
            }
            else
            {
                minutes += val;
            }
        }
        /// <summary>
        /// Adds the passed hour value to the timestamp
        /// </summary>
        /// <param name="val">Added hours</param>
        private void AddHours(int val)
        {
            if (hours + val >= 24)
            {
                AddDays (val / 24);
                hours = (val % 24);
            }
            else
            {
                hours += val;
            }
        }
        /// <summary>
        /// Adds the passed days value to the timestamp
        /// </summary>
        /// <param name="val">Added days</param>
        private void AddDays(int val)
        {
            short dayCount = GetDayMaxDaysOfMonth(month, year);
            if (dayOfMonth + val > dayCount)
            {
                AddMonths(val / dayCount);
                dayOfMonth = (val % dayCount);
            }
            else
            {
                dayOfMonth += val;
            }
        }
        /// <summary>
        /// Adds the passed month value to the timestamp
        /// </summary>
        /// <param name="val">Added months</param>
        private void AddMonths(int val)
        {
            if (month + val > 12)
            {
                AddYears(val / 12);
                month = (val % 12);
            }
            else
            {
                month += val;
            }
        }
        /// <summary>
        /// Adds the passed value to the year part of the time stamp
        /// </summary>
        /// <param name="val">Years to be added</param>
        private void AddYears(int val)
        {
            year += val;
        }

        /// <summary>
        /// Returns true if the the parameter matches this instance.
        /// </summary>
        /// <remarks>
        /// See <see cref="DoMatch"/>
        /// </remarks>
        /// <param name="other">The parameter to compare</param>
        /// <returns>true|false</returns>
        public override bool Equals(object o)
        {
            if (o is SyslogTimestamp)
            {
                return DoMatch((SyslogTimestamp)o, this);
            }
            else
            {
                return false;
            }
        }
        /// <summary>
        /// Returns true if a & b match, else false.
        /// </summary>
        /// <remarks>
        /// Match criteria:
        /// (a.year == b.Year)
        /// && (a.month == b.Month)
        /// && (a.dayOfMonth == b.DayOfMonth)
        /// && (a.hours == b.Hours)
        /// && (a.minutes == b.Minutes)
        /// && (a.seconds == b.Seconds)
        /// && (a.miliseconds == b.Miliseconds)
        /// && (a.utcOffset == b.UtcOffset);
        /// </remarks>
        public static bool DoMatch(SyslogTimestamp a, SyslogTimestamp b)
        {
            bool doMatch = (a.year == b.Year)
                && (a.month == b.Month)
                && (a.dayOfMonth == b.DayOfMonth)
                && (a.hours == b.Hours)
                && (a.minutes == b.Minutes)
                && (a.seconds == b.Seconds)
                && (a.miliseconds == b.Miliseconds)
                && (a.utcOffset == b.UtcOffset);

            return doMatch;
        }
        /// <summary>
        /// The overloaded == operator
        /// </summary>
        /// <remarks>
        /// see http://msdn.microsoft.com/en-us/library/ms173147(v=vs.80).aspx
        /// </remarks>
        public static bool operator ==(SyslogTimestamp a, SyslogTimestamp b)
        {
            // If both are null, or both are same instance, return true.
            if (System.Object.ReferenceEquals(a, b))
            {
                return true;
            }

            // If one is null, but not both, return false.
            if (((object)a == null) || ((object)b == null))
            {
                return false;
            }

            return DoMatch(a, b);
        }
        /// <summary>
        /// The overloaded != operator.
        /// </summary>
        /// <remarks>
        /// see http://msdn.microsoft.com/en-us/library/ms173147(v=vs.80).aspx
        /// </remarks>
        public static bool operator !=(SyslogTimestamp a, SyslogTimestamp b)
        {
            return !(a == b);
        }
        /// <summary>
        /// The smaller than Operator
        /// compares every date|time related field with
        /// the other and returns true if the left hand side of
        /// the assignement is smaller than the right hand side
        /// </summary>
        /// <param name="a"></param>
        /// <param name="b"></param>
        /// <returns></returns>
        public static bool operator <(SyslogTimestamp a, SyslogTimestamp b)
        {
            if (a.Year < b.Year) { return true; }
            if (a.Year > b.Year) { return false; }

            if (a.Month < b.Month) { return true; }
            if (a.Month > b.Month) { return false; }

            if (a.DayOfMonth < b.DayOfMonth) { return true; }
            if (a.DayOfMonth > b.DayOfMonth) { return false; }

            if ((a.Hours + a.UtcOffset) < (b.Hours + b.UtcOffset)) { return true; }
            if ((a.Hours + a.UtcOffset) > (b.Hours + b.UtcOffset)) { return false; }

            if (a.Minutes < b.Minutes) { return true; }
            if (a.Minutes > b.Minutes) { return false; }

            if (a.Seconds < b.Seconds) { return true; }
            if (a.Seconds > b.Seconds) { return false; }

            if (a.Miliseconds < b.Miliseconds) { return true; }
            if (a.Miliseconds > b.Miliseconds) { return false; }

            return false;
        }
        /// <summary>
        /// The greater than Operator
        /// compares every date|time related field with
        /// the other and returns true if the left hand side of
        /// the assignement is greater than the right hand side
        /// </summary>
        /// <param name="a"></param>
        /// <param name="b"></param>
        /// <returns></returns>
        public static bool operator >(SyslogTimestamp a, SyslogTimestamp b)
        {
            if (a.Year > b.Year) { return true; }
            if (a.Year < b.Year) { return false; }

            if (a.Month > b.Month) { return true; }
            if (a.Month < b.Month) { return false; }

            if (a.DayOfMonth > b.DayOfMonth) { return true; }
            if (a.DayOfMonth < b.DayOfMonth) { return false; }

            if ((a.Hours + a.UtcOffset) > (b.Hours + b.UtcOffset)) { return true; }
            if ((a.Hours + a.UtcOffset) < (b.Hours + b.UtcOffset)) { return false; }

            if (a.Minutes > b.Minutes) { return true; }
            if (a.Minutes < b.Minutes) { return false; }

            if (a.Seconds > b.Seconds) { return true; }
            if (a.Seconds < b.Seconds) { return false; }

            if (a.Miliseconds > b.Miliseconds) { return true; }
            if (a.Miliseconds < b.Miliseconds) { return false; }

            return false;
        }
        /// <summary>
        /// greater or equal Operator
        /// </summary>
        /// <param name="a"></param>
        /// <param name="b"></param>
        /// <returns>(a > b) || DoMatch(a, b)</returns>
        public static bool operator >=(SyslogTimestamp a, SyslogTimestamp b)
        {
            return (a > b) || DoMatch(a, b);
        }
        /// <summary>
        /// smaller or equal Operator
        /// </summary>
        /// <param name="a"></param>
        /// <param name="b"></param>
        /// <returns><code>(a { b) || DoMatch(a, b)</code></returns>
        public static bool operator <=(SyslogTimestamp a, SyslogTimestamp b)
        {
            return (a < b) || DoMatch(a, b);
        }

        /// <summary>
        /// Returns the Hash code of the object
        /// </summary>
        /// <returns>Hash code</returns>
        public override int GetHashCode()
        {
            return base.GetHashCode();
        }
    }
}

string[] formats = { "yyyy-MM-dd\\THH:mm:ss\\Z", 
                     "yyyy-MM-dd\\THH:mm:ss.f\\Z", 
                     "yyyy-MM-dd\\THH:mm:ss.ff\\Z", 
                     "yyyy-MM-dd\\THH:mm:ss.fff\\Z", 
                     "yyyy-MM-dd\\THH:mm:ss.ffff\\Z", 
                     "yyyy-MM-dd\\THH:mm:ss.fffff\\Z", 
                     "yyyy-MM-dd\\THH:mm:ss.ffffff\\Z", 
                     "yyyy-MM-dd\\THH:mm:sszzz", 
                     "yyyy-MM-dd\\THH:mm:ss.fzzz", 
                     "yyyy-MM-dd\\THH:mm:ss.ffzzz", 
                     "yyyy-MM-dd\\THH:mm:ss.fffzzz", 
                     "yyyy-MM-dd\\THH:mm:ss.ffffzzz", 
                     "yyyy-MM-dd\\THH:mm:ss.fffffzzz", 
                     "yyyy-MM-dd\\THH:mm:ss.ffffffzzz" 
                   };

DateTime dt1 = default(DateTime);
bool res1 = System.DateTime.TryParseExact("1985-04-12T20:20:59.100000-00:15", 
                                           formats, System.Globalization.CultureInfo.InvariantCulture, 
                                           System.Globalization.DateTimeStyles.AdjustToUniversal, 
                                           out dt1);

DateTime dt2 = default(DateTime);
bool res2 = System.DateTime.TryParseExact("1985-04-12T20:20:59.100001-00:15", 
                                          formats, System.Globalization.CultureInfo.InvariantCulture, 
                                          System.Globalization.DateTimeStyles.AdjustToUniversal,
                                          out dt2);

Console.WriteLine(dt1.Kind.ToString()); // yep UTC
Console.WriteLine(dt1.ToString("u"));
Console.WriteLine((dt1 < dt2).ToString()); // 1 µsec less

DateTimeOffset dto1 = new DateTimeOffset();
bool res1b = System.DateTimeOffset.TryParseExact("1985-04-12T20:20:59.100000-00:15", 
                                                 formats, 
                                                 System.Globalization.CultureInfo.InvariantCulture, 
                                                 System.Globalization.DateTimeStyles.AssumeLocal, 
                                                 out dto1);

Bernhard Hiller wrote:

get its data into appropriate objects