Specifies the precise timing when a particular key frame should take place during the relative course of an animation.
When used as a KeyTime, specifies a key time for a frame at 15 seconds.
In the grammar above, square brackets () indicate optional values; the brackets are not literals. The colon (:) and period (.) characters are both literals.
Values for hours can be any integer value from 0 through 23. Values for minutes and seconds can be any integer value from 0 through 59. The value for days can be very large, but it does have an unspecified upper bound. The decimal value for fractionalSeconds (with the decimal point included) must be between 0 and 1.
You can creating a Duration, KeyTime, RepeatBehavior, or TimeSpan object in XAML or in script only through a type conversion syntax when you set a property (such as KeyTime (ColorKeyFrame)) that takes one of these types, with the value specified as a string. The string format for specifying a time in each of these types is identical.
The main scenario for working with a KeyTime as an object in script is to get or set its Seconds property to query or change an existing animation value.
The typical time span is in seconds. Therefore, the KeyTime string would include preceding 0 values for hours and minutes, along with the appropriate literal characters—colons (:) and periods (.)—as separators between hours, minutes, seconds, and fractions of seconds. For example, to specify a KeyTime of 5 seconds, you would set the KeyTime string to "0:0:5" ("0:0:05" is equivalent).
If you specify a KeyTime by an integer without any time span literal characters—colons (:) or periods (.)—the integer will be interpreted only as a number of days. This is seldom the intended result and will typically cause the KeyTime to be unexpectedly large.