apps
latest
false
- Getting Started
- Demo apps
- How To
- Build Your First App
- Build a Mobile-Friendly App
- General User Experience Guidelines
- Use Master Detail View
- Use Document Viewer
- Use Count With Choice Set Values
- Use Selected Values From a Table
- Embed Apps
- Embed Maps
- Hide Containers Using a Button
- Include MailTo Links
- Include Star Ratings
- Set External Context
- Work With Data Source and Value Bind
- Use the Send Interim Result Activity
- Public Apps
- Notifications
- Using VB Expressions
- Designing your App
- Events and Rules
- Rule: If-Then-Else
- Rule: Open a Page
- Rule: Open URL
- Rule: Close Pop-Over/Bottom Sheet
- Rule: Show Message
- Rule: Show/Hide Spinner
- Rule: Set Values
- Rule: Start Process
- Rule: Upload File to Storage Bucket
- Rule: Get File From Storage Bucket
- Rule: Reset Values
- Rule: Create/Update Entity Record
- Rule: Delete Entity Record
- Rule: Add to Queue
- Function: And, Or, Not
- Function: Concat
- Function: Contains
- Function: Count
- Function: EndsWith
- Function: If
- Function: IsBlank
- Function: Guid
- Function: Length
- Function: List
- Function: StartsWith
- Function: Sum
- Function: Sort
- Function: Now
- Function: Today
- Function: Time
- Function: Year
- Function: Month
- Function: Day
- Function: Hour
- Function: Minute
- Function: New
- Function: Lookup
- Function: Filter
- Leveraging RPA in your App
- Leveraging Entities in Your App
- Leveraging Queues in Your App
- Leveraging Media in your app
- Leveraging Actions in your app
- Leveraging Connections in your apps
- Application Lifecycle Management (ALM)
- UiPath First-Party Apps
- Basic Troubleshooting Guide
Useful VB functions
important :
For documentation on app projects in Studio Web, refer to the App Projects chapter in the Studio Web documentation: https://docs.uipath.com/studio-web/automation-cloud/latest/user-guide/apps-in-studio-web.

LEGACY
Apps User Guide
Last updated Aug 5, 2024
This page contains VB expressions that you may find useful while building your app.
We grouped several of these functions in a public app, so you can try out them out and see how they behave.
The
Where()
function returns a zero-based array containing a subset of a string array based on a specified filter criteria.
Assume you have a variable called
words
defined as List(Of String) = {"apple", "banana", "cherry", "date"}
.
To get the list of words that contain the letter "a", apply the
Where()
function as follows:
words.Where(Function(w) w.Contains("a")).ToList()
words.Where(Function(w) w.Contains("a")).ToList()
The output is
{"apple", "banana", "date"}
.
The
Select()
function creates a new array that contains the results of applying a lambda expression to each element in the source array.
Assume you have a variable called
numbers
defined as Integer() = {1, 2, 3, 4, 5}
.
To get the list of numbers multiplied by themselves, apply the The output is
Select()
function as follows:numbers.Select(Function(n) n * n).ToArray()
numbers.Select(Function(n) n * n).ToArray()
{1, 4, 9, 16, 25}
.
The
Aggregate()
function performs calculations over all the elements in an array and returns a single value.
Assume you have a variable called
numbers
defined as Integer() = {1, 2, 3, 4, 5}
.
To get the sum of all the numbers in the array, apply the Aggregate() function as follows:The output is
Dim sum = numbers.Aggregate(Function(acc, n) acc + n)
Dim sum = numbers.Aggregate(Function(acc, n) acc + n)
15
.
The
GroupBy()
function groups elements in a sequence by a key selector function.
Assume you have a variable called
words
defined as String() = {"apple", "banana", "cherry", "date"}
.
To group the words by the first letter, which is the key selector function, apply the The output is
GroupBy()
function as follows:words.GroupBy(Function(w) w(0))
words.GroupBy(Function(w) w(0))
{ {"a", "apple", "date"}, {"b", "banana"}, {"c", "cherry"} }
.
The
OrderBy()
and OrderByDescending()
functions sort elements in a sequence based on a key selector function.
Assume you have a variable called
words
defined as String() = {"apple", "banana", "cherry", "date"}
.
To order the words by their length, which is the key selector function, apply the The output is
OrderBy()
function as follows:words.OrderBy(Function(w) w.Length).ToArray()
words.OrderBy(Function(w) w.Length).ToArray()
{"date", "apple", "cherry", "banana"}
.
The
Join()
function combines elements in two sequences based on a key selector function.
Assume you have two variables:
-
names
defined asString() = {"John", "Jane", "Joe"}
-
ages
defined asInteger() = {25, 30, 35}
To combine the elements in the first sequence with the elements in the second sequence, apply the The output is
Join()
function as follows:names.Join(ages, Function(name) name(0), Function(age) age Mod 10, Function(name, age) $"{name}: {age}")
names.Join(ages, Function(name) name(0), Function(age) age Mod 10, Function(name, age) $"{name}: {age}")
{"John: 25", "Jane: 30", "Joe: 35"}
.
The
First()
function returns the first element in a sequence that satisfies a specified condition.
Assume you have a variable called
numbers
defined as Integer() = {1, 2, 3, 4, 5}
.
To get the first even number in the sequence, apply the The output is
First()
function as follows:numbers.First(Function(n) n Mod 2 = 0)
numbers.First(Function(n) n Mod 2 = 0)
2
.
The
FirstOrDefault()
function returns the first element, or a default value if no element satisfies the condition.
Assume you have a variable called
numbers
defined as Integer() = {1, 2, 3, 4, 5}
.
To get the first odd number in the sequence, apply the The output is
FirstOrDefault()
function as follows:numbers.FirstOrDefault(Function(n) n Mod 2 = 1)
numbers.FirstOrDefault(Function(n) n Mod 2 = 1)
1
.
The
Last()
function returns the last element in a sequence that satisfies a specified condition.
Assume you have a variable called
numbers
defined as Integer() = {1, 2, 3, 4, 5}
.
To get the first even number in the sequence, apply the The output is
last()
function as follows:numbers.Last(Function(n) n Mod 2 = 0)
numbers.Last(Function(n) n Mod 2 = 0)
4
.
The
LastOrDefault()
function returns the last element, or a default value if no element satisfies the condition.
Assume you have a variable called
numbers
defined as Integer() = {1, 2, 3, 4, 5}
.
To get the first odd number in the sequence, apply the The output is
FirstOrDefault()
function as follows:numbers.LastOrDefault(Function(n) n Mod 2 = 1)
numbers.LastOrDefault(Function(n) n Mod 2 = 1)
5
.
The
Skip()
function skips a specified number of elements in a sequence.
Assume you have a variable called
numbers
defined as Integer() = {1, 2, 3, 4, 5}
.
To skip the first two elements in the sequence, apply the The output is
Skip()
function as follows:numbers.Skip(2).ToArray()
numbers.Skip(2).ToArray()
{3, 4, 5}
.
The
SkipWhile()
function skips elements until a condition is no longer satisfied.
Assume you have a variable called
numbers
defined as Integer() = {1, 2, 3, 4, 5}
.
To skip the numbers which are lower than 3, apply the The output is
SkipWhile()
function as follows:numbers.SkipWhile(Function(n) n < 3).ToArray()
numbers.SkipWhile(Function(n) n < 3).ToArray()
{3, 4, 5}
.
The
Take()
function returns a specified number of elements from the start of a sequence.
Assume you have a variable called
numbers
defined as Integer() = {1, 2, 3, 4, 5}
.
To get the first three elements in the sequence, apply the The output is
Take()
function as follows:numbers.Take(3).ToArray()
numbers.Take(3).ToArray()
{1, 2, 3}
.
The
TakeWhile()
returns elements until a condition is no longer satisfied.
Assume you have a variable called
numbers
defined as Integer() = {1, 2, 3, 4, 5}
.
To get the numbers which are lower than 4, apply the The output is
TakeWhile()
function as follows:numbers.TakeWhile(Function(n) n < 4).ToArray()
numbers.TakeWhile(Function(n) n < 4).ToArray()
{1, 2, 3}
.
The
Any()
function returns true
if any element in a sequence satisfies a specified condition.
Assume you have a variable called
numbers
defined as Integer() = {1, 2, 3, 4, 5}
.
To find out if at least one number in the sequence is even, apply the The output is
Any()
function as follows:numbers.Any(Function(n) n Mod 2 = 0)
numbers.Any(Function(n) n Mod 2 = 0)
true
.
The
All()
returns true
if all elements in a sequence satisfy a specified condition.
Assume you have a variable called
numbers
defined as Integer() = {1, 2, 3, 4, 5}
.
To find out if all the numbers in the sequence are positive, apply the The output is
All()
function as follows:numbers.All(Function(n) n > 0)
numbers.All(Function(n) n > 0)
true
.
The list function
AddItemToList()
adds a new item to an existing list.
Assume you want to manipulate the records in an Edit Grid control with data from a process integration, using the Set Value rule. The item to set is
Processes.ALLDATATYPES.out_genericList
.
To add an item to the generic list, assign it the following value:
AddItemToList(Processes.ALLDATATYPES.out_genericList, MainPage.EditGrid.NewItem)
AddItemToList(Processes.ALLDATATYPES.out_genericList, MainPage.EditGrid.NewItem)
The list function
DeleteItemFromList()
deletes items from an existing list.
Assume you want to manipulate the records in an Edit Grid control with data from a process integration, using the Set Value rule. The item to set is
Processes.ALLDATATYPES.out_genericList
.
To delete an item from the generic list, assign it the following value:
DeleteItemFromList(Processes.ALLDATATYPES.out_genericList, MainPage.EditGrid.RowIndex)
DeleteItemFromList(Processes.ALLDATATYPES.out_genericList, MainPage.EditGrid.RowIndex)
The list function
UpdateListItemAtIndex()
updates items in an existing list.
Assume you want to manipulate the records in an Edit Grid control with data from a process integration, using the Set Value rule. The item to set is
Processes.ALLDATATYPES.out_genericList
.
To update an item in the generic list, assign it the following value:
UpdateListItemAtIndex(Processes.ALLDATATYPES.out_genericList, MainPage.EditGrid.RowIndex, MainPage.EditGrid.SelectedItem)
UpdateListItemAtIndex(Processes.ALLDATATYPES.out_genericList, MainPage.EditGrid.RowIndex, MainPage.EditGrid.SelectedItem)
- Useful VB functions
- VB function: Where
- VB function: Select
- VB function: Aggregate
- VB function: Group By
- VB function: Order By
- VB function: Join
- VB function: First
- VB function: First Or Default
- VB function: Last
- VB function: Last Or Default
- VB function: Skip
- VB function: Skip While
- VB function: Take
- VB function: Take While
- VB function: Any
- VB function: All
- VB function: Add item to list
- VB function: Delete item from list
- VB function: Update list item at index