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SecurityToken.ValidFrom Property

Definition

Gets the first instant in time at which this security token is valid.

public:
 abstract property DateTime ValidFrom { DateTime get(); };
public abstract DateTime ValidFrom { get; }
member this.ValidFrom : DateTime
Public MustOverride ReadOnly Property ValidFrom As DateTime

Property Value

A DateTime that represents the instant in time at which this security token is first valid.

Examples

The code examples that are used in the SecurityToken topics are taken from the Custom Token sample. This sample provides custom classes that enable processing of Simple Web Tokens (SWT). It includes an implementation of a SimpleWebToken class and a SimpleWebTokenHandler class, as well as other classes that support SWT tokens. For information about this sample and other samples available for WIF and about where to download them, see WIF Code Sample Index. The following code shows the override of the ValidFrom property.

/// <summary>
/// Defines the set of constants for the Simple Web Token.
/// </summary>
public static class SimpleWebTokenConstants
{
    public const string Audience = "Audience";
    public const string ExpiresOn = "ExpiresOn";
    public const string Id = "Id";
    public const string Issuer = "Issuer";
    public const string Signature = "HMACSHA256";
    public const string ValidFrom = "ValidFrom";
    public const string ValueTypeUri = "http://schemas.xmlsoap.org/ws/2009/11/swt-token-profile-1.0";     
}
public static DateTime SwtBaseTime = new DateTime( 1970, 1, 1, 0, 0, 0, 0 ); // per SWT psec

NameValueCollection _properties;
/// <summary>
/// Gets the time from when the token is valid.
/// </summary>
/// <value>The time from when the token is valid.</value>
public override DateTime ValidFrom
{
    get 
    {
        string validFrom = _properties[SimpleWebTokenConstants.ValidFrom];
        return GetTimeAsDateTime( String.IsNullOrEmpty( validFrom ) ? "0" : validFrom );
    }
}
/// <summary>
/// Converts the time in seconds to a <see cref="DateTime"/> object based on the base time 
/// defined by the Simple Web Token.
/// </summary>
/// <param name="expiryTime">The time in seconds.</param>
/// <returns>The time as a <see cref="DateTime"/> object.</returns>
protected virtual DateTime GetTimeAsDateTime( string expiryTime )
{
    long totalSeconds = 0;
    if ( !long.TryParse( expiryTime, out totalSeconds ) )
    {
        throw new SecurityTokenException("Invalid expiry time. Expected the time to be in seconds passed from 1 January 1970.");
    }

    long maxSeconds = (long)( DateTime.MaxValue - SwtBaseTime ).TotalSeconds - 1;
    if ( totalSeconds > maxSeconds )
    {
        totalSeconds = maxSeconds;
    }

    return SwtBaseTime.AddSeconds( totalSeconds );
}

Remarks

Use the ValidFrom and ValidTo properties to determine the time period in which a SecurityToken token is valid. The ValidFrom and ValidTo properties represent the first and last instants in time in which the security token is valid, respectively.

Notes to Implementers

You must override the ValidFrom property.

Applies to