I have a textBox where the user enters a datetime using a calendar, I am checking for whether the text box is empty or not by
if ((string.IsNullOrEmpty(txt_SendAt.Text) == false)
How can I check whether the datetime entered is less or = to the current datetime
if ((string.IsNullOrEmpty(txt_SendAt.Text) == false
&& DateTime.Parse(txt_SendAt.Text) <= DateTime.Now )
DateTime enteredDateTime;
if (!DateTime.TryParse(txt_SendAt.Text, out enteredDateTime))
{
Debug.WriteLine("User entered date time in wrong format");
}else
{
if(enteredDateTime <= DateTime.Now)
{
// less or equal
}
}
Parse or TryParse the text to DateTime, then compare to DateTime.Now
A few steps here, first check something is entered, as you have done, secondly, check it is actually a date, and lastly check against the desired date, as such:
var input = DateTextBox.Text;
if (!string.IsNullOrEmpty(input))
{
DateTime date;
if (DateTime.TryParse(input, out date))
{
if (date <= DateTime.Now)
{
//bingo!
}
}
}
Notice the TryParse for checking proper formatting of the input string as a date - using only Parse is a sure way to make your app go BANG!
You can parse your string input to a DateTime using the DateTime.Parse method, then run your comparison in the normal way.
Remember, Parse methods will throw a FormatException if the input is not directly castable to the required type. It may make more sense to go for the TryParse method if you have, for example, a free-text input.
var inputDate = DateTime.Parse(txt_SendAt.Text);
if (inputDate > DateTime.Now)
{
Console.WriteLine("DateTime entered is after now.");
}
else if (inputDate < DateTime.Now)
{
Console.WriteLine("DateTime entered is before now.");
}
Use one of the Parse or TryParse static methods of the DateTime class to convert the string to a DateTime and compare it to the current DateTime.
DateTime input;
if(DateTime.TryParse(txt_SendAt.Text,
CultureInfo.InvariantCulture,
DateTimeStyles.None,
out input))
{
if(input <= DateTime.Now)
{
// your code here
}
}
else
{
//not a valid DateTime string
}
if (!(string.IsNullOrEmpty(txt_SendAt.Text) && Datetime.Parse(txt_SendAt.Text)<=Datetime.Now)
{
/*code */
}
else
{
/*code */
}
Related
I have a text box where user enters date in format "YYYY-MM-DD". I have to check whether the entered date is current date as per the server date. If both the date matches then only proceed further. I have to check only the date not date time.
<input type="text" class="form-control input_text" runat="server" id="englishDate9"/>
So how can I check this, is it possible to use asp validator or I have to do it from code behind?
#region date check section
string sysDt = englishDate9.Value;
DateTime oDate = DateTime.Parse(sysDt).Date;
DateTime sysdate = DateTime.Now.Date;
if(oDate == sysdate)
{
// show message
}
#endregion
I am using this code, but I am confused is this the correct code or not although for now it is giving correct result for me?
Hope this will help.
DateTime oDate;
if(DateTime.TryParse(englishDate9.Value, out oDate))
{
if(oDate != DateTime.Today)
{
return;
}
}
else
{
return;
}
You should do like this. because string any be anything thing other than the valid date and the required format.
string dateString = "2009-06-20";
DateTime dt;
bool isValid = DateTime.TryParseExact(dateString, "yyyy-MM-dd", CultureInfo.InvariantCulture, DateTimeStyles.None, out dt);
DateTime sysdate = DateTime.Now.Date;
if (isValid == true && DateTime.Now.Date == sysdate)
{
//Do something
}
This question already has answers here:
Parse string to DateTime in C#
(9 answers)
Checking Date format from a string in C#
(8 answers)
Closed 3 years ago.
I want to check if a string is in yyyyMMddHHmmss format in C#. What is the best way to do it.
Here I have tried with DateTime.TryParse, but it always return false.
string currentFileName = "Test_File_20190312122838";
string timestampValue = currentFileName.Substring(currentFileName.LastIndexOf('_')+ 1);
DateTime outDate = DateTime.Now;
if (DateTime.TryParse(timestampValue, out outDate)) // always return false
{
}
Note: Sometimes timestampValue may contain normal text instead of a timestamp value.
TryParse doesn't have overload to provide exact format, try using TryParseExact. Example:
// adjust IFormatProvider and DateTimeStyles if needed
if (DateTime.TryParseExact(
timestampValue,
"yyyyMMddHHmmss", //format
CultureInfo.CurrentCulture,
DateTimeStyles.None, out outDate))
{
//do work
}
Use TryParseExact
string currentFileName = "Test_File_20190312122838";
string timestampValue = currentFileName.Split('_')[2];
// if your naming convention is not always the same, you may want to leave the resolving of the timestampvalue as you did
// string timestampValue = currentFileName.Substring(currentFileName.LastIndexOf('_')+ 1);
DateTime outDate = DateTime.Now;
if (DateTime.TryParseExact(timestampValue, "yyyyMMddHHmmss",
CultureInfo.CurrentCulture, System.Globalization.DateTimeStyles.None, out outDate))
{
// whatever you want to do...
}
https://learn.microsoft.com/en-us/dotnet/api/system.datetime.tryparseexact?view=netframework-4.7.2
I hope this piece of code may help you
public static bool IsValidDateTime(string dateTime)
{
long lCheck;
dateTime = dateTime.Trim();
//check if its valid integers
bool status = long.TryParse(dateTime, out lCheck);
//if its not valid long value or length does not conforms the format throw an exception or return false
if (!status || dateTime.Length != 14)
throw new Exception("Input does not conforms yyyyMMddHHmmss fromat");
try
{
DateTime.ParseExact(dateTime.ToString(), "yyyyMMddHHmmss", System.Globalization.CultureInfo.InvariantCulture);
}
catch (Exception exp)
{
return false;
}
//everything is well lets return true
return true;
}
Please advise how I can check that current date (DateTime.Now) is in diapason of dates in format "dd/mm". For example - 01.01 <= DateTime.Now <= 01.03 - Current date more that 1st of January but less that 1st of March
Let dateStrFrom be the first input ie, the From Date and dateStrTo be the second input ie, the To date. Then you can use DateTime.TryParseExact to convert it into the required DateTime Object for processing your comparison.
I hope that you are looking for something like this :
string dateStrFrom = "01.01";
string dateStrTo = "01.03";
DateTime dateFrom, dateTo;
DateTime.TryParseExact(dateStrFrom, "dd.MM", CultureInfo.InvariantCulture, DateTimeStyles.None, out dateFrom);
DateTime.TryParseExact(dateStrTo, "dd.MM", CultureInfo.InvariantCulture, DateTimeStyles.None, out dateTo);
if (dateFrom <= DateTime.Now && dateTo <= DateTime.Now)
{
// code here this will be the true condition for you
}
DateTime dt1 = DateTime.ParseExact("01/01", "dd/MM",null);
DateTime dt2 = DateTime.ParseExact("28/11", "dd/MM", null);
if (dt1 <= DateTime.Now && DateTime.Now < dt2)
{
MessageBox.Show("hi");
}
if someone find the solution, thanks
Try this:
DateTime.Compare(DateTime.Now, DateTime.ParseExact("01.03", "dd.MM", null))
This returns a signed number indicating the relative values of t1 and t2.Value Type Condition Less than zero t1 is earlier than t2. Zero t1 is the same as t2. Greater than zero t1 is later than t2.
You can parse using DateTime.Parse(). For your case you can using the DateTime.Compare()
Sample code will help you.
// If you want to compare only date part of DateTime, not time part:
DateTime d1 = DateTime.Parse("10/11/2016");
DateTime d2 = DateTime.Parse("01/01/2016");
if (d1.Date > d2.Date)
{
// do the stuff
}
// For Converting it to String
DateTime.Now.ToString("MM/dd/yyyy");
DateTime.Today.ToString("MM/dd/yyyy");
// Comparison
int result = DateTime.Compare(today, otherdate);
if(result < 0)
MessageBox.Show("Today is earlier than the 'otherdate'");
elseif(result > 0)
MessageBox.Show("Today is later than the 'other date'");
else
MessageBox.Show("Dates are equal...");
// Will give you a DateTime typed object
var dateTime = DateTime.Parse("01/01/2016");
I am working on a calendar. And here I want to check if the users input is a date and if it's not showing an error. I heard about DateTime.TryParse. How can I use this here properly? Can maybe anyone explain it in simple words?
public void addMeeting()
{
string readAddMeeting;
var dateFormats = new[] {"dd.MM.yyyy", "dd-MM-yyyy", "dd/MM/yyyy"}; // I copied this
Console.WriteLine("Add a schedule for specific dates: ");
readAddMeeting = Console.ReadLine();
}
Use DateTime.TryParseExact in this way:
public void addMeeting()
{
var dateFormats = new[] {"dd.MM.yyyy", "dd-MM-yyyy", "dd/MM/yyyy"};
Console.WriteLine("Add a schedule for specific dates: ");
string readAddMeeting = Console.ReadLine();
DateTime scheduleDate;
bool validDate = DateTime.TryParseExact(
readAddMeeting,
dateFormats,
DateTimeFormatInfo.InvariantInfo,
DateTimeStyles.None,
out scheduleDate);
if(validDate)
Console.WriteLine("That's a valid schedule-date: {0}", scheduleDate.ToShortDateString());
else
Console.WriteLine("Not a valid date: {0}", readAddMeeting);
}
The method returns a bool indicating whether it could be parsed or not and you pass a DateTime variable as out parameter which will be initialized if the date was valid.
Note that i'm using DateTimeFormatInfo.InvariantInfo because you don't want to use the local DateTime format but one that works in any culture. Otherwise the / in dd/MM/yyyy would be replaced with your current culture's date separators. Read
Even if it sounds a bit brutal, but it seems ike you should do some readup on arrays/lists, foreach loops and DateTime.TryParse.
That aside you have different possible date formats and want to see if one of them is valid. If we take the example from the msdn homepage for tryparse https://msdn.microsoft.com/en-us/library/ch92fbc1(v=vs.110).aspx and use foreach it becomes quite easy:
public void addMeeting()
{
string readAddMeeting;
var dateFormats = new[] {"dd.MM.yyyy", "dd-MM-yyyy", "dd/MM/yyyy"}; // I copied this
bool isDateOk = false;
Console.WriteLine("Add a schedule for specific dates: ");
readAddMeeting = Console.ReadLine();
foreach (string myDateFormat in dateFormats)
{
DateTime dateValue;
if (DateTime.TryParse(readAddMeeting, dateValue))
{
isDateOk = true;
}
}
if (isDateOk == false)
{
Console.Writeline("Sorry this is not a valid date");
}
}
I have a textbox where i will enter date in mm/dd/yyyy format,i want to compare this textbox date with current date(sysdate) in javascript code in c#.How to do that??Example i enter 11/11/2011 which is future date and it must be checked with sysdate and print an message
example
DateTime.ParseExact(txtDate.Text, "mm/dd/yyyy",null) > DateTime.Today
DateTime dateValue;
string dateString = textBox.Text;
if (DateTime.TryParse(dateString, out dateValue))
{
// Use Date.CompareTo as you want to...
int result = DateTime.Compare(dateValue, DateTime.Today);
if (result > 0)
{
//Future Date
}
}