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Duration Data type

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Version: Available or changed with runtime version 1.0.

Represents the difference between two DateTimes. This value can be negative. It is stored as a 64-bit integer. The integer value is the number of milliseconds during the duration.

The following are examples of durations:

DateTime-DateTime=Duration

DateTime-Duration=DateTime

DateTime+Duration=DateTime

The value of the Duration data type can also be explicitly defined in milliseconds.

Example 1

This example shows how to calculate the difference between two DateTimes. This example is run on a computer with the Current Format in the Regional and Language Options set to English (United States).

var
    DateTime1: DateTime;
    DateTime2: DateTime;
    Duration: Duration;
begin
    DateTime1 := CreateDateTime(20090101D, 080000T); // January 1, 2009 at 08:00:00 AM  
    DateTime2 := CreateDateTime(20090505D, 133001T); // May 5, 2009 at 1:30:01 PM  
    Duration := DateTime2 - DateTime1;  
    Message(Format(Duration));  
end;

The message window displays the following:

124 days 4 hours 30 minutes 1 second

Example 2

The following example shows how to specify the duration of a timeout in milliseconds.

procedure GetDefaultTimeout(): Duration
var
     Timeout: Duration;
begin
    Timeout := 1000 * 60 * 60; // One hour
    exit(Timeout);
end

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