CultureInfo.DateTimeFormat Property

Gets or sets a DateTimeFormatInfo object that defines the culturally appropriate format for converting dates and times to strings.

Namespace:  System.Globalization
Assembly:  mscorlib (in mscorlib.dll)

Public Overridable Property DateTimeFormat As DateTimeFormatInfo

Property Value

Type: System.Globalization.DateTimeFormatInfo
An object that defines the culturally appropriate format for converting dates and times to strings.


The property is set to Nothing.


The DateTimeFormat property or any of the DateTimeFormatInfo properties is set, and the CultureInfo is read-only.

The user might choose to override some of the values associated with the current system culture. For example, the user might choose to display the date in a different format or to use a currency other than the default for the culture. The DateTimeFormatInfo object returned by the current culture's DateTimeFormat property reflects these overrides.

The values of the DateTimeFormat property and the NumberFormat property are not populated until the property is accessed. If the application changes the current culture to a new culture while the application is running and then the application accesses the DateTimeFormat or NumberFormat property, the application retrieves the defaults for the new culture instead of the overrides for the original culture. To preserve the overrides for the original current culture, the application should access the DateTimeFormat and NumberFormat properties before changing the current culture.

Notes to Callers

If DateTimeFormatInfo.Calendar is the TaiwanCalendar but the Thread.CurrentCulture is not "zh-TW", then DateTimeFormatInfo.GetEraName and DateTimeFormatInfo.GetAbbreviatedEraName return an empty string ("").

The following example shows that the Clone method also clones the DateTimeFormatInfo and NumberFormatInfo instances associated with the CultureInfo object.

Imports System.Globalization

Public Class Example
   Public Shared Sub Demo(ByVal outputBlock As System.Windows.Controls.TextBlock)
      ' Creates and initializes a CultureInfo object.
      Dim myCI As New CultureInfo("en-US")

      ' Clones myCI and modifies the DTFI and NFI instances associated with the clone.
      Dim myCIclone As CultureInfo = CType(myCI.Clone(), CultureInfo)
      myCIclone.DateTimeFormat.AMDesignator = "a.m."
      myCIclone.NumberFormat.CurrencySymbol = "USD"
      myCIclone.NumberFormat.NumberDecimalDigits = 4

      ' Displays the properties of the DTFI and NFI instances associated with the original and with the clone. 
      outputBlock.Text &= "DTFI/NFI PROPERTY" + ControlChars.Tab + "ORIGINAL" + ControlChars.Tab + "MODIFIED CLONE" & vbCrLf
      outputBlock.Text += String.Format("DTFI.AMDesignator" + ControlChars.Tab + "{0}" + ControlChars.Tab + ControlChars.Tab + "{1}", myCI.DateTimeFormat.AMDesignator, myCIclone.DateTimeFormat.AMDesignator) & vbCrLf
      outputBlock.Text += String.Format("NFI.CurrencySymbol" + ControlChars.Tab + "{0}" + ControlChars.Tab + ControlChars.Tab + "{1}", myCI.NumberFormat.CurrencySymbol, myCIclone.NumberFormat.CurrencySymbol) & vbCrLf
      outputBlock.Text += String.Format("NFI.NumberDecimalDigits" + ControlChars.Tab + "{0}" + ControlChars.Tab + ControlChars.Tab + "{1}", myCI.NumberFormat.NumberDecimalDigits, myCIclone.NumberFormat.NumberDecimalDigits) & vbCrLf
   End Sub  

End Class 
' This example produces the following output.
'       DTFI.AMDesignator       AM              a.m.
'       NFI.CurrencySymbol      $               USD
'       NFI.NumberDecimalDigits 2               4


Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

XNA Framework

Supported in: Xbox 360, Windows Phone OS 7.0

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.

Community Additions