VBScript - Working With Time Values

Basics

Objects and Functions for Working With Time Values

Getting Current Time

Formatted Output of Time Values

Encoding and Decoding Time Values

Modifying Time Values

Comparing Time Values

Using the StopWatch Object

Operations over time values are very similar to operations over dates. Each time value includes a date part and vice versa.

Since the TestComplete scripting engine only supports OLE-compatible data types, the date-time values are implemented as floating-point variant values in a special format. The integer part of this value represents the number of days that have passed since December 30, 1899. The number after the decimal separator is time partition: it represents the fraction of a 24-hour period that has elapsed. However, you do not have to understand what these floating-point values represent. TestComplete provides several routines that help you convert these values to their string representation (see below).

Below are some examples of date-time values and their meaning:

When you are only working with time values the integer part can be omitted. However the time value can vary more than 24 hours and may result in a date-time value that has an integer part.

TestComplete has an aqDateTime object that contains methods that can be useful when operating with date-time values.

Another object, aqConvert, provides methods to convert between date values and their string equivalents:

The aqDateTime and aqConvert objects are available for all supported scripting languages, so that you can use them to operate with date values regardless of the chosen language.

VBScript has two functions with names that coincide with the names of aqDateTime’s methods. They are Time and Now. If the object name precedes the function name (for instance, aqDateTime.Now), then a TestComplete method is called; if the object name is missing (for instance, Now), then a built-in function of VBScript is called.

You can also use these and other built-in VBScript functions in your scripts. Here is a list of built-in functions that can be useful when dealing with dates:

There are two routines that return current time: Time and Now. The difference between them is that the value returned by the Now routine includes both the date and time parts, whereas the Time routine returns only the time part. The script below demonstrates how to use them.

The same date-time value can be represented in various formats. The aqConvert object has two methods that convert date/time values to a string using the conventional or user-defined formats. These methods are DateTimeToStr and DateTimeToFormatStr.

The DateTimeToStr method returns a string that represents the date and time according to current locale. If a date/time value holds only the time portion, the routine does not display the date part.

The DateTimeToFormatStr method allows greater flexibility since it accepts the format specifier string as one of the parameters. It is capable of forming a string of date and time portions together or in parts. To learn how the resulting format is defined, see Date and Time Format Specifiers.

Here is a sample that illustrates how to use these methods:

Because the date-time values are implemented as variants, special routines are required that convert the variant value to common representation. These operations are performed by the SetTimeElements, GetHours, GetMinutes and GetSeconds methods of the aqDateTime object. SetTimeElements accepts the time parts and returns a variant date/time value.

The GetHours, GetMinutes and GetSeconds methods perform a contrary operation: they accept a variant date/time value and return the time parts of that value. Here is an example of how to use these routines:

The aqDateTime scripting object has a number of methods that alter the time portions of the provided date/time value. These methods are: AddHours, AddMinutes, AddSeconds and AddTime. Despite their names, these methods can both increase and decrease the corresponding time portions. When the value of an argument (Days, Hours, Minutes or Seconds) is a positive number, the methods add the specified number of days, hours, minutes or seconds to the input date/time. When an argument’s value is a negative number, the input date/time is decreased by the given number. The AddTime method allows you to change several time portions simultaneously.

The methods were designed for date/time values, so they guarantee that the resulting values will be valid. Thus, for example, changing the minutes portion automatically increases the hours portion if the resulting number of minutes exceeds 59 minutes.

The code snippet below demonstrates how to use these methods:

To compare date/time values, use the aqDateTime.Compare method rather than comparison operators (like =, >, <, <> and others) provided by the scripting engine:

Sometimes we need to measure the time that has passed between two events, for example between the beginning and end of a test. This can be done in two ways: using the time-handling routines of the aqDateTime object and using the StopWatch object that is provided by the HISUtils plugin.

In the first case you should obtain the current time before and after the event, and calculate the interval between them (for example, with the aqDateTime.TimeInterval method).

In the second case you should create an instance of StopWatch object, start the time count using the StopWatch.Start method, execute the desired operation and then stop the counter using the StopWatch.Stop method.

Here is a code sample that demonstrates how to use both of these techniques:

As you can see both methods are equivalent, but the StopWatch object has a special method called ToString, that transforms the time counter value into a string. Furthermore, the object has the Split method that allows you to get the time counter value without stopping the counter. This could be useful when displaying the elapsed time during a series of tests: