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DateTimeOffset.TryParse Method (String, IFormatProvider, DateTimeStyles, DateTimeOffset%)

Microsoft Silverlight will reach end of support after October 2021. Learn more.

Tries to convert a specified string representation of a date and time to its DateTimeOffset equivalent, and returns a value that indicates whether the conversion succeeded.

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

Syntax

'Declaration
Public Shared Function TryParse ( _
    input As String, _
    formatProvider As IFormatProvider, _
    styles As DateTimeStyles, _
    <OutAttribute> ByRef result As DateTimeOffset _
) As Boolean

public static bool TryParse(
    string input,
    IFormatProvider formatProvider,
    DateTimeStyles styles,
    out DateTimeOffset result
)

Parameters

  • input
    Type: System.String
    A string that contains a date and time to convert.
  • formatProvider
    Type: System.IFormatProvider
    An object that provides culture-specific formatting information about input.
  • result
    Type: System.DateTimeOffset%
    When the method returns, contains the DateTimeOffset value equivalent to the date and time of input, if the conversion succeeded, or MinValue, if the conversion failed. The conversion fails if the input parameter is nulla null reference (Nothing in Visual Basic) or does not contain a valid string representation of a date and time. This parameter is passed uninitialized.

Return Value

Type: System.Boolean
true if the input parameter is successfully converted; otherwise, false.

Exceptions

Exception Condition
ArgumentException

styles includes an undefined DateTimeStyles value.

-or-

DateTimeStyles.NoCurrentDateDefault is not supported.

-or-

styles includes mutually exclusive DateTimeStyles values.

Remarks

This overload of the TryParse(String, IFormatProvider, DateTimeStyles, DateTimeOffset%) method is like the DateTimeOffset.Parse(String, IFormatProvider, DateTimeStyles) method, except that it does not throw an exception if the conversion fails. The method parses a string with three elements that can appear in any order and are delimited by white space. These three elements are shown in the following table.

Element

Example

<Date>

"2/10/2007"

<Time>

"1:02:03 PM"

<Offset>

"-7:30:15"

Although each of these elements is optional, <Offset> cannot appear by itself. It must be provided together with either <Date> or <Time>. If <Date> is missing, its default value is the current day. If <Time> is missing, its default value is 12:00:00 AM. If <Offset> is missing, its default value is the offset of the local time zone, or Zero if either the DateTimeStyles.AdjustToUniversal or DateTimeStyles.AssumeUniversal value is specified in styles. If <Offset> is present, it can represent either a negative or a positive offset from Coordinated Universal Time (UTC). In either case, <Offset> must include a sign symbol or the method returns false.

The input string is parsed by using the culture-specific formatting information in a DateTimeFormatInfo object supplied by the formatProvider parameter. The formatProvider parameter can be either of the following:

In addition, each element can be delimited by leading or trailing white space, and the <Date> and <Time> components can include inner white space (such as 6: 00:00). Only the <Offset> component cannot include inner white space.

If provider is nulla null reference (Nothing in Visual Basic), the CultureInfo object that corresponds to the current culture is used to define valid date and time formats.

The positive or negative sign used in <Offset> must be either + or -. It is not defined by the PositiveSign or NegativeSign properties of the NumberFormatInfo object returned by the formatprovider parameter's NumberFormat property.

The following members of the DateTimeStyles enumeration are supported:

DateTimeStyles Member

Comments

AdjustToUniversal

Parses the string represented by input and, if necessary, converts it to UTC. It is equivalent to parsing a string, and then calling the returned object's ToUniversalTime() method.

AllowInnerWhite

Although valid, this value is ignored. Inner white space is allowed in the <Date> and <Time> components.

AllowLeadingWhite

Although valid, this value is ignored. Leading white space is allowed in front of each component in the parsed string.

AllowTrailingWhite

Although valid, this value is ignored. Trailing white space is allowed in front of each component in the parsed string.

AllowWhiteSpaces

This is the default behavior. It cannot be overridden by supplying a more restrictive DateTimeStyles enumeration value, such as DateTimeStyles.None.

AssumeLocal

Indicates that, if the input parameter lacks an <Offset> element, the offset of the local time zone should be provided. This is the default behavior of the TryParse(String, IFormatProvider, DateTimeStyles, DateTimeOffset%) method.

AssumeUniversal

Indicates that, if the input parameter lacks an <Offset> element, the UTC offset (00:00) should be provided.

None

Although valid, this value is ignored and has no effect.

RoundtripKind

Because the DateTimeOffset structure does not include a Kind property, this value has no effect.

Only the DateTimeStyles.NoCurrentDateDefault value is not supported. An ArgumentException is thrown if this value is included in the styles parameter.

Examples

The following example calls the TryParse(String, IFormatProvider, DateTimeStyles, DateTimeOffset%) method with a variety of DateTimeStyles values to parse some strings with various date and time formats.

Dim dateString As String
Dim parsedDate As DateTimeOffset

dateString = "05/01/2008 6:00:00"
' Assume time is local 
If DateTimeOffset.TryParse(dateString, Nothing, _
                           DateTimeStyles.AssumeLocal, _
                           parsedDate) Then
   outputBlock.Text += String.Format("'{0}' was converted to to {1}.", _
                     dateString, parsedDate.ToString()) + vbCrLf
Else
   outputBlock.Text += String.Format("Unable to parse '{0}'.", dateString) & vbCrLf
End If

' Assume time is UTC
If DateTimeOffset.TryParse(dateString, Nothing, _
                           DateTimeStyles.AssumeUniversal, _
                           parsedDate) Then
   outputBlock.Text += String.Format("'{0}' was converted to to {1}.", _
                     dateString, parsedDate.ToString()) + vbCrLf
Else
   outputBlock.Text += String.Format("Unable to parse '{0}'.", dateString) & vbCrLf
End If

' Parse and convert to UTC 
dateString = "05/01/2008 6:00:00AM +5:00"
If DateTimeOffset.TryParse(dateString, Nothing, _
                           DateTimeStyles.AdjustToUniversal, _
                           parsedDate) Then
   outputBlock.Text += String.Format("'{0}' was converted to to {1}.", _
                     dateString, parsedDate.ToString()) + vbCrLf
Else
   outputBlock.Text += String.Format("Unable to parse '{0}'.", dateString) & vbCrLf
End If
' The example displays the following output:
'    '05/01/2008 6:00:00' was converted to to 5/1/2008 6:00:00 AM -07:00.
'    '05/01/2008 6:00:00' was converted to to 5/1/2008 6:00:00 AM +00:00.
'    '05/01/2008 6:00:00AM +5:00' was converted to to 5/1/2008 1:00:00 AM +00:00.      

string dateString;
DateTimeOffset parsedDate;

dateString = "05/01/2008 6:00:00";
// Assume time is local 
if (DateTimeOffset.TryParse(dateString, null as IFormatProvider,
                            DateTimeStyles.AssumeLocal,
                            out parsedDate))
   outputBlock.Text += String.Format("'{0}' was converted to to {1}.",
                     dateString, parsedDate.ToString()) + "\n";
else
   outputBlock.Text += String.Format("Unable to parse '{0}'.", dateString) + "\n";

// Assume time is UTC
if (DateTimeOffset.TryParse(dateString, null as IFormatProvider,
                            DateTimeStyles.AssumeUniversal,
                            out parsedDate))
   outputBlock.Text += String.Format("'{0}' was converted to to {1}.",
                     dateString, parsedDate.ToString()) + "\n";
else
   outputBlock.Text += String.Format("Unable to parse '{0}'.", dateString) + "\n";

// Parse and convert to UTC 
dateString = "05/01/2008 6:00:00AM +5:00";
if (DateTimeOffset.TryParse(dateString, null as IFormatProvider,
                           DateTimeStyles.AdjustToUniversal,
                           out parsedDate))
   outputBlock.Text += String.Format("'{0}' was converted to to {1}.",
                     dateString, parsedDate.ToString()) + "\n";
else
   outputBlock.Text += String.Format("Unable to parse '{0}'.", dateString) + "\n";
// The example displays the following output:
//    '05/01/2008 6:00:00' was converted to to 5/1/2008 6:00:00 AM -07:00.
//    '05/01/2008 6:00:00' was converted to to 5/1/2008 6:00:00 AM +00:00.
//    '05/01/2008 6:00:00AM +5:00' was converted to to 5/1/2008 1:00:00 AM +00:00.

Version Information

Silverlight

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

Platforms

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