studio
2020.10
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Studio User Guide
Last updated Dec 20, 2023

Control Flow Activities

The Assign Activity

The Assign activity is an important activity that is going to be used quite often, as it enables you to assign a value to a variable.

You can use an Assign activity to increment the value of a variable in a loop (see the example in the The Do While Activity chapter), sum up the value of two or more variables and assign the result to another variable (see the example in the Generic Value Variables), assign values to an array (see Array Variables) and so on.

By default, this activity is also included in the Favorites group. To remove it, right-click it and select Remove.

The Delay Activity

The Delay activity enables you to pause the automation for a custom period of time (in the hh:mm:ss format). This activity proves itself quite useful in projects that require good timing, such as waiting for a specific application to start or waiting for some information to be processed so that you can use it in another activity.

Example of Using the Delay Activity

To exemplify how you can best use the Delay activity, let's create an automation that writes two messages to the Output panel, with a delay of 20 seconds between them.

  1. Create a new flowchart.
  2. Add a Write Line activity and connect it to the Start node.
  3. Select the activity, and in the Text field, type "This is the start time."
  4. Add a Delay activity and connect it to the previously added activity.
  5. Select the activity, and in the Properties panel, in the Duration field, type 00:00:20. This is the 20 seconds delay that is going to be between the two logged messages.
  6. Add another Write Line activity and connect it to the previously added activity.
  7. In the Text field, type "Message delayed by 20 seconds.".

    The final project should look as in the following screenshot.



  8. Press F5. The automation is executed. Note that, in the Output panel, the two messages added in the Write Line activities are written twenty seconds apart.


The Do While Activity

The Do While activity enables you to execute a specified part of your automation while a condition is met. When the specified condition is no longer met, the project exits the loop.

This type of activity can be useful to step through all the elements of an array, or execute a particular activity multiple times. You can increment counters to browse through array indices or step through a list of items.

Note: Do While activities are evaluated only after the body has been executed once.

Example of Using a Do While Activity

To exemplify how to use a Do While activity, let’s create an automation that increments an integer variable from 0 to 10, and displays a message every time it is incremented.

  1. Create a new sequence.
  2. Create an integer variable, Counter, with a default value of 0.
  3. Add a Do While activity to the Designer panel.
  4. In the Body section, add an Assign activity.
  5. Select the Assign activity, and in the Properties panel, in the To field, add the Counter variable.
  6. In the Value field, type Counter + 1. This helps you increment the value of the variable with one.
  7. Add a Write Line activity, under the Assign one.
  8. In the Text field, type "The counter is " + Counter.ToString. This writes the value of the counter in the Output panel each time it is incremented.
  9. In the Condition section of the Do While activity, type Counter < 10. The body of the Do While activity is repeated until the value of the Counter variable is bigger than 10.

    The project should look as in the following screenshot.



  10. Press F5. The automation is executed. Note that the Output panel displays the message indicated in the Write Line activity.


The If Activity

The If activity contains a statement and two conditions. The first condition (the activity in the Then section) is executed if the statement is true, while the second one (the activity in the Else section) is executed if the statement is false.

If activities can be useful to make decisions based on the value of variables.

Note: The If activity is almost identical to the Flow Decision one. However, the latter can only be used in flowcharts.

Example of Using an If Activity

To exemplify how you can use the If activity, let’s create an automation that asks the user for two numbers, checks to see if one is divisible by the other, and depending on the result, displays a different message in the Output panel.

  1. Create a new sequence.
  2. Create two integer variables, FirstNumber and SecondNumber for example.
  3. Add two Input Dialog activities to the Designer panel.
  4. In the Properties panel, type labels and titles for both activities and, in the Result fields, add the FirstNumber and SecondNumber variables.
  5. Add an If activity to the Designer panel, under the previously added Input Dialog ones.
  6. In the Condition section, type FirstNumber mod SecondNumber = 0. This expression checks if the first number is divisible to the second one, using the mod operator.
  7. In the Then section, add a Write Line activity.
  8. In the Text field, type FirstNumber.ToString + " is divisible by "+ SecondNumber.ToString + ".". This is the message that is displayed if the first number is divisible by the second one.
  9. In the Else section, add another Write Line activity.
  10. In the Text field, type FirstNumber.ToString + " is NOT divisible by "+ SecondNumber.ToString + ".". This is the message that is displayed if the first number is not divisible with the second one.


  11. Press F5. The automation is executed.
  12. Add numbers when prompted. Note that the Output panel displays the result, depending on the values added in the Input Dialog windows.




The Switch Activity

The Switch activity enables you to select one choice out of multiple, based on the value of a specified expression.

By default, the Switch activity uses the integer argument, but you can change it from the Properties panel, from the TypeArgument list.

The Switch activity can be useful to categorize data according to a custom number of cases. For example, you can use it to store data into multiple spreadsheets or sort through names of employees.

Example of Using a Switch Activity

To exemplify how to use the Switch activity, we are going to create an automation that asks the user for a number, checks if is odd or even, and depending on that, a different message is written to the Output panel.

Since all odd numbers divided by two have a remainder equal to 1, this project needs only two cases (0 and 1) , yet keep in mind that this activity supports multiple cases.

  1. Create a new sequence.
  2. Create an integer variable, Number.
  3. Add an Input Dialog activity to the Designer panel.
  4. Add a Title and Label to prompt the user for a number.
  5. In the Result field, add the Number variable.
  6. Add a Switch activity, under the Input Dialog.
  7. In the Expression field, type Number mod 2. This verifies if the user’s number is divisible by 2.
  8. In the Default section, add a Write Line activity.
  9. In the Text field, type Number.ToString + " is an even number.".
  10. Click the Add new case line, and in the Case Value field, type 1.
  11. Add a Write Line activity to this case.
  12. In the Text activity, type Number.ToString + " is an odd number.".

    The final project should look as in the following screenshot.



  13. Press F5. The automation is executed. Note that the Output panel displays the data correctly.




The While Activity

The While activity enables you to execute a specific process repeatedly, while a specific condition is met. The main difference between this and the Do While activity is that, in the first one, the condition is evaluated before the body of the loop is executed.

This type of activity can be useful to step through all the elements of an array, or execute a particular activity multiple times. You can increment counters to browse through array indices or step through a list of items.

Example of Using a While Activity

To exemplify how to use a While activity, let’s create an automation that increments an integer variable from 10 to 100, and writes all the numbers to a Microsoft Word document.

  1. Create a new sequence.
  2. Create an integer variable, Counter, with the default value of 10.
  3. Add a While activity to Designer panel.
  4. In the Condition field, type Counter < 100. This means that the body of the loop is going to be repeated until the value of the Counter variable is going to be bigger than 100.
  5. In the Body section of the While activity, add an Assign activity.
  6. In the Properties panel, in the To field add the Counter.
  7. In the Value field, type Counter + 1. This increments the value of the Counter with one.
  8. Add an Append Text activity under the Assign one.
    Note: This activity is part of the Word activities package. If you do not have it, use the package manager functionality to install it.
  9. In the FilePath field, type the path of a Word document in between quotation marks.
    Note: Make sure that the Word document is not used when running the automation, otherwise a message error is displayed and the execution is stopped.
  10. In the Text field, type "The counter is now " + Counter.ToString +".".

    The final project should look as in the following screenshot.



  11. Press F5. The automation is executed.
  12. Double-click the Word document specified at step 9. Note that all the numbers between 10 and 100 are written, as expected.


The For Each Activity

The For Each activity enables you to step through arrays, lists, data tables or other types of collections, so that you can iterate through the data and process each piece of information individually.

Example of Using a For Each Activity

To exemplify how to use a For Each activity, let’s create an automation that goes through each element of an array of integers and writes the length of the array and each element to the Output panel.

  1. Create a new sequence.
  2. Create an array of integer variables, FibonacciNumbers.
  3. In the Default field, type the Fibonacci sequence up to a desired value, such as {1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89}.
  4. Add a For Each activity in the Designer panel.
  5. Do not make any changes to the Foreach field.
  6. In the In field, add the FibonacciNumbers variable. This activity looks at each individual item in the provided variable.
  7. In the Body section of the For Each activity, add a Write Line activity.
  8. In the Text field, type "The length of this Fibonacci sequence is " + FibonacciNumbers.Length.ToString + " and contains the " + item.ToString + " element.". This expression enables you to write the total number of array elements and each element of the array in the Output panel.

    The final project should look as in the following screenshot.



  9. Press F5. The automation is executed. Note that the Output panel displays the correct message for each element of the array.
    Note: The Length property enables you to find out the total number of array elements.


The Break Activity

The Break activity enables you to stop the loop at a chosen point, and then continues with the next activity.

Note:

The Break activity can only be used within one of the following activities: For Each, While, or Do While.

Example of Using a Break Activity

To exemplify how to use the Break activity we are going to build upon the project created for The For Each Activity. This new project writes only the first iteration of the loop and a few elements of the array to the Output panel.

  1. In the Body of the For Each activity, under the Write Line, add a Break activity.
  2. Under the For Each, add a new Write Line activity.
  3. In the Text field, type FibonacciNumbers(0).ToString + " " + FibonacciNumbers(2).ToString + " " + FibonacciNumbers(4).ToString + " " + FibonacciNumbers(6).ToString + " " + FibonacciNumbers(8).ToString + " " + FibonacciNumbers(10).ToString + " ". This means that only the indicated elements of the array are going to be written to the Output panel.

    The final project should look as in the following screenshot.



  4. Press F5. The automation is executed. Note that the Output panel only displays the first iteration of the loop and the specified array elements from the Write Line activity.


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