DateConvert library

derez

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• Jan 28, 2010

• #1

The attached library is converting dates from Gregorian or Julian calendars to Hebrew calendar, and vice versa.

It operates on dates from 100 AD.

It operates on desktop and Device.

Requires .NET 2.0

Includes a MoonPhase method, as I found that this functionality of the Hebrew calendar is useful with GPS programs (more than the dates...).

I hope it will be useful to someone. I plan to use it in my Family tree program and in the double calendar program.

Edit: updated to ver 1.1, includes two methods for finding if a year is a Leap year.
Edit: version 1.2 to "immune" against different system regional formats of Date and Time.
Edit: updated to ver 1.3 which can accept dd/mm/yyy or mm/dd/yyyy formats, no matter which regional setting you have.
Edit: ver 1.4 now its done automatically, no need to declare it in New1.

 

Attachments

• DateConvert1.4.zip

  18.3 KB · Views: 76

Last edited: Feb 1, 2010

derez

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• Jan 28, 2010

• #2

Ver 1.1 , addition of two methods.

 

derez

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• Jan 28, 2010

• #3

I have a frustrating problem with this library.
When I run an application that use it on my laptop - by the IDE or after compilation, everything works fine.

When I run the same application on my Desktop - it fails whenever it uses the library.

both computers run windows XP. :sign0085:

 

Last edited: Jan 28, 2010

Erel

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• Jan 28, 2010

• #4

You are implicitly using the local computer regional settings (with DateTime.Parse(date) and maybe other methods as well)
Maybe one computer has different settings than the other.

 

W

wm.chatman

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• Jan 28, 2010

• #5

Hello derez

code is still hard to understand, for me. But, I Love your MoonPhase method.

William

 

derez

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• Jan 28, 2010

• #6

Erel
I am trying to change the format of the date but it does not help.

Can you please check if it runs for you ?

William

I think the code is simple. What isn't clear to you ? I'll be glad to explain.

 

Erel

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• Jan 28, 2010

• #7

It is failing here because currently my computer default date format is mm/dd/yy and not dd/mm/yy.

 

derez

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• Jan 28, 2010

• #8

Erel
I found this in the .net:

public static DateTimeFormatInfo InvariantInfo { get;}
belongs to system.Globalization

But I don't have a clue what to do with it.
It is supposed to make the dateTime formats invariant to the culture.

I found this http://primates.ximian.com/~lupus/corlib-cov/class-System.Globalization.DateTimeFormatInfo.html file of the Globalization namespace.

 

Last edited: Jan 28, 2010

derez

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• Jan 28, 2010

• #9

Erel
I changed in my computer the regional settings to Hebrew, so the short date format (which was like yours) changed to dd/mm/yyyy and immediately the program runs like a speedboat.

Now can you help me define the library to become invariant to the format ??

Of course I can change the library to the other format but than it will cause problems to other computers.

Thanks.:BangHead:

 

Last edited: Jan 28, 2010

derez

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• Jan 28, 2010

• #10

:sign0060::sign0060::sign0060:

I added this line:
IFormatProvider culture = new System.Globalization.CultureInfo("fr-FR", true);

and now it does not matter if I use English us (mm/dd/yyyy) or united kingdom (dd/mm/yyyy) or hebrew (dd/mm/yyyy) - it works.

I am updating the library.

 

Last edited: Jan 28, 2010

derez

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• Jan 29, 2010

• #11

I was glad too early, found out this:

The value of the DateTimeFormat property and the NumberFormat property is not calculated until you access the property. If you use the Control Panel to change the current culture to a new culture while your application is running then access the DateTimeFormat or NumberFormat property, your application will get the defaults for the new culture not the overrides for the original culture

Click to expand...

If the application is already open in the IDE, the change in the control panel\regional settings does not affect it !

So I still need a way to make the library insensitive to the date format.:sign0085:

In the meantime, if anyone (?) wants to code an application with this library, make the regional settings compatible to dd/mm/yyyy.

 

Last edited: Jan 29, 2010

agraham

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• Jan 30, 2010

• #12

I think you have misunderstood what a CultureInfo does. You have created a "fr-FR" CultureInfo but you never actually use it! You need to specify it when you are parsing something otherwise the System settings are used.

DateTime dt = DateTime.Parse(date, culture)

 

derez

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• Jan 30, 2010

• #13

Thank you Andrew, I already understood it the hard way.

But I managed to work around this problem, starting always with a neutral date (like 1.1.2000) and adding the days, months and years.

I updated the library, with true or false in the New1 it can accept either dd/mm/yyyy or mm/dd/yyyy formats.

 

derez

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• Feb 1, 2010

• #14

I found the way to get the used format and change the library behaviour accordingly.

Updated in ver 1.4, the New1 is now without an argument.

 

W

wm.chatman

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• Feb 1, 2010

• #15

derez said:

Erel
I am trying to change the format of the date but it does not help.

Can you please check if it runs for you ?

William

I think the code is simple. What isn't clear to you ? I'll be glad to explain.

Click to expand...

Sorry I just now got to answer you derez. Post #7 help me. Now I understand why your sample did not work.

Take care.

William