How to filter between a dates from string and datetimepicker

Question

I am trying to filter through things by date. I have 2 DateTimePicker called FromDate and ToDate. I have an array and within one of the array (str[10]) is a date, I tried converting the string into a datetime format but I still get the error:

System.FormatException: 'String was not recognized as a valid DateTime.'

The string within str[10]:

str[10] = "9/22/2017 18:24";

My current code:

string[] date = str[10].Split(' ');                            
DateTime dateSpec = DateTime.ParseExact(date[0], "MM/dd/yyyy", CultureInfo.CurrentCulture);
if (dateSpec >= FromDate.Value && dateSpec <= ToDate.Value) 
{ 
   //Do Something
}

I am not so sure what to do as most forums suggest more or less the same thing. I'm not sure where the error is. I checked the array and the string does not have any spaces as well, thinking that it may have been the reason as to why there was an error

but the thing is, I just wanted to filter it by date unless it is a must with the time as well? bc the array date[0] is just the date "9/22/2017" — Allysha April
– Allysha April, Commented Apr 8, 2022 at 7:35
Why are you using strings instead of DateTime object in the first place? If you absolutely have to use strings, use they ISO8601 format, YYYY-MM-DD. It's the only unambiguous format and is recognized by DateTime.Parse — Panagiotis Kanavos
– Panagiotis Kanavos, Commented Apr 8, 2022 at 8:14
Using string instead bc the data of the dates are in an excel file that I had imported into a listbox filtered with only the things i need to see (other data eg: name, etc..), so I wanted to filter it further — Allysha April
– Allysha April, Commented Apr 8, 2022 at 8:26

Lance U. Matthews · Accepted Answer · 2022-04-08 08:13:05Z

2

The MM in "MM/dd/yyyy" means the month component will be padded with a 0, if necessary, to make it two digits long. Your input, "9/22/2017", uses only a single-digit month and so doesn't match that format. If you change the format to "M/dd/yyyy" it parses successfully.

Also, you don't need to truncate the time portion yourself; if the time format is consistent (HH : mm) then just parse it and use the Date property to get a DateTime for midnight of the same day...

DateTime dateSpec = DateTime.ParseExact(str[10], "M/dd/yyyy HH:mm", CultureInfo.CurrentCulture);
if (dateSpec.Date >= FromDate.Value && dateSpec.Date <= ToDate.Value) 
{ 
    //Do Something
}

Depending on how str is populated (e.g. user input) also consider using DateTime.TryParseExact(), which returns false upon failure rather than throwing a FormatException...

if (DateTime.TryParseExact(str[10], "M/dd/yyyy HH:mm", CultureInfo.CurrentCulture, DateTimeStyles.None, out DateTime dateSpec))
{
    // Handle parsing success

    if (dateSpec.Date >= FromDate.Value && dateSpec.Date <= ToDate.Value) 
    { 
        //Do Something
    }
}
else
{
    // Handle parsing failure
}

dateSpec is declared at the point it is passed as an out parameter, which is possible since C# 7.0.

edited Apr 8, 2022 at 8:13

answered Apr 8, 2022 at 7:40

Lance U. Matthews

16.8k6 gold badges52 silver badges71 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Allysha April Over a year ago

I am not sure as to why it still isn't working. I tried changing the format to M/d/yyyy H:mm because I looked back onto the list of dates that I have but it still has the same error as an invalid format

Lance U. Matthews Over a year ago

What input string(s) is it failing on? "9/22/2017 18:24" parses for me with "M/d/yyyy H:mm". Did you change the first argument passed to ParseExact() from date[0] to str[10]? What is the value of CultureInfo.CurrentCulture.DisplayName?

Allysha April · Accepted Answer · 2022-04-08 09:35:13Z

-2

I managed to get it working by adding this block of code from another coder's suggestion on another platform

string[] formats = { "M/d/yyyy HH:mm", "M/dd/yyyy HH:mm", "MM/d/yyyy HH:mm", "MM/dd/yyyy HH:mm" };
DateTime dateSpec = DateTime.Now;
if (DateTime.TryParseExact(str[10].ToString(), formats, System.Globalization.CultureInfo.CurrentCulture, System.Globalization.DateTimeStyles.None, out dateSpec))
{
    if (dateSpec.Date >= FromDate.Value.Date && dateSpec.Date <= ToDate.Value.Date)
        {
            //Do Something
        }
}
else
{
    MessageBox.Show("Error");
}

answered Apr 8, 2022 at 9:35

Allysha April

234 bronze badges

1 Comment

Lance U. Matthews Over a year ago

This is effectively the same as the second code snippet in my answer except you're passing (guessing at?) four formats instead of one. I have confirmed that, in the invariant and en-US cultures, M/d/yyyy HH:mm successfully parses all four combinations of one- and two-digit months and days; MM fails to parse a single-digit month (9) so your last 2, if not 3, formats here seem unnecessary. It's hard to see how this answer will be useful to anyone but yourself when you provided only one sample input and didn't respond to my clarifying questions in response to your comment on my answer.

Collectives™ on Stack Overflow

How to filter between a dates from string and datetimepicker

2 Answers 2

2 Comments

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

2 Comments

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related