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DateTimeOffset.Parse Method (String, IFormatProvider, DateTimeStyles)

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Converts the specified string representation of a date and time to its DateTimeOffset equivalent using the specified culture-specific format information and formatting style.

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

Syntax

'Declaration
Public Shared Function Parse ( _
    input As String, _
    formatProvider As IFormatProvider, _
    styles As DateTimeStyles _
) As DateTimeOffset

public static DateTimeOffset Parse(
    string input,
    IFormatProvider formatProvider,
    DateTimeStyles styles
)

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 format information about input.

Return Value

Type: System.DateTimeOffset
An object that is equivalent to the date and time that is contained in input, as specified by formatProvider and styles.

Exceptions

Exception Condition
ArgumentException

The offset is greater than 14 hours or less than -14 hours.

-or-

styles is not a valid DateTimeStyles value.

-or-

styles includes an unsupported DateTimeStyles value.

-or-

styles includes DateTimeStyles values that cannot be used together.
ArgumentNullException

input is nulla null reference (Nothing in Visual Basic).
FormatException

input does not contain a valid string representation of a date and time.

-or-

input contains the string representation of an offset value without a date or time.

Remarks

This 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 TimeSpan.Zero if either the DateTimeStyles.AdjustToUniversal or DateTimeStyles.AssumeUniversal value is specified in the styles parameter. 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.

The format of these three elements is defined by the formatProvider parameter, which can be either of the following:

Each element can also be enclosed by leading or trailing white space, and the <Date> and <Time> elements can include inner white space (such as 6: 00:00). Only the <Offset> component cannot include inner white space.

If formatprovider is nulla null reference (Nothing in Visual Basic), the CultureInfo object that corresponds to the current culture is used to determine the specific valid formats for date and time elements

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.

The following table shows the members of the System.Globalization.DateTimeStyles enumeration that are supported.

DateTimeStyles member

Description

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 DateTimeOffset.ToUniversalTime method of the returned DateTimeOffset object.

AllowInnerWhite

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

AllowLeadingWhite

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

AllowTrailingWhite

Although valid, this value is ignored. Trailing white space is permitted 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 Parse 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 illustrates the effect of passing the DateTimeStyles.AssumeLocal, DateTimeStyles.AssumeUniversal, and DateTimeStyles.AdjustToUniversal values to the styles parameter of the Parse(String, IFormatProvider, DateTimeStyles) method.

Dim dateString As String
Dim offsetDate As DateTimeOffset

dateString = "05/01/2008 6:00:00"
' Assume time is local 
offsetDate = DateTimeOffset.Parse(dateString, Nothing, DateTimeStyles.AssumeLocal)
outputBlock.Text &= offsetDate.ToString() & vbCrLf   ' Displays 5/1/2008 6:00:00 AM -07:00

' Assume time is UTC
offsetDate = DateTimeOffset.Parse(dateString, Nothing, DateTimeStyles.AssumeUniversal)
outputBlock.Text &= offsetDate.ToString() & vbCrLf   ' Displays 5/1/2008 6:00:00 AM +00:00

' Parse and convert to UTC 
dateString = "05/01/2008 6:00:00AM +5:00"
offsetDate = DateTimeOffset.Parse(dateString, Nothing, DateTimeStyles.AdjustToUniversal)
outputBlock.Text &= offsetDate.ToString() & vbCrLf   ' Displays 5/1/2008 1:00:00 AM +00:00

string dateString;
DateTimeOffset offsetDate;

dateString = "05/01/2008 6:00:00";
// Assume time is local 
offsetDate = DateTimeOffset.Parse(dateString, null, DateTimeStyles.AssumeLocal);
outputBlock.Text += offsetDate.ToString() + "\n";   // Displays 5/1/2008 6:00:00 AM -07:00

// Assume time is UTC
offsetDate = DateTimeOffset.Parse(dateString, null, DateTimeStyles.AssumeUniversal);
outputBlock.Text += offsetDate.ToString() + "\n";   // Displays 5/1/2008 6:00:00 AM +00:00

// Parse and convert to UTC 
dateString = "05/01/2008 6:00:00AM +5:00";
offsetDate = DateTimeOffset.Parse(dateString, null, DateTimeStyles.AdjustToUniversal);
outputBlock.Text += offsetDate.ToString() + "\n";   // Displays 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.