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Comprehensive Guide to Validations in Power Platform: Best Practices for Controls

Validation is the foundation of integrity of data and user-friendly apps. You can use validations on controls in Power Platform to ensure that the data you are getting and processing is reliable. We are going to cover a broad variety of validation scenarios and how you can use them in Power Platform in the following section.

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1. Age Validation

Scenario: Ensure that the user’s age is 18 or above.

Implementation:

• Use a Date Picker control to capture the user’s date of birth.
• Add a formula to validate the age:

If(DateDiff(DateValue(DateOfBirth.SelectedDate), Today(), TimeUnit.Years) < 18, Notify("You must be at least 18 years old.", NotificationType.Error))

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2. Email Validation

Scenario: Ensure the entered email address is in the correct format.

Implementation:

• Use a Text Input control to capture the email.
• Validate the email using a regular expression:

If(!IsMatch(EmailInput.Text, “^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+.[a-zA-Z]{2,}$”), Notify(“Please enter a valid email address.”, NotificationType.Error))

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3. Weekend Date Validation

Scenario: Restrict the selection of weekend dates.

Implementation:

• Use a Date Picker control.
• Add a formula to validate the selected date:

If(Weekday(DatePicker.SelectedDate) in [1, 7], Notify("Weekends are not allowed.", NotificationType.Error))

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4. Phone Number Validation

Scenario: Ensure the entered phone number follows a specific format (e.g., 10 digits).

Implementation:

• Use a Text Input control.
• Validate using a regular expression:

If(!IsMatch(PhoneNumber.Text, "^\d{10}$"), Notify("Please enter a valid 10-digit phone number.", NotificationType.Error))

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5. Required Field Validation

Scenario: Ensure mandatory fields are not left empty.

Implementation:

• Use the If function to check for blank values:

If(IsBlank(TextInput.Text), Notify("This field is required.", NotificationType.Error))

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6. Numeric Range Validation

Scenario: Validate that a number falls within a specific range (e.g., 1 to 100).

Implementation:

• Use a Text Input control and validate:

If(Value(NumericInput.Text) < 1 || Value(NumericInput.Text) > 100, Notify("Value must be between 1 and 100.", NotificationType.Error))

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7. Prevent Duplicate Entries

Scenario: Prevent users from entering duplicate values.

Implementation:

• Use a Gallery or Collection to check existing values:

If(LookUp(DataSource, FieldName = TextInput.Text, true), Notify("Duplicate entry detected.", NotificationType.Error))

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8. Future Date Restriction

Scenario: Ensure a date field does not allow future dates.

Implementation:

• Use a Date Picker control:

If(DatePicker.SelectedDate > Today(), Notify("Future dates are not allowed.", NotificationType.Error))

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9. Special Character Restriction

Scenario: Prevent the use of special characters in a text field.

Implementation:

• Use the IsMatch function:

If(IsMatch(TextInput.Text, "[!@#$%^&*(),.?\":{}|<>]"), Notify("Special characters are not allowed.", NotificationType.Error))

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10. Password Complexity Validation

Scenario: Enforce a strong password policy (e.g., minimum 8 characters, includes letters, numbers, and special characters).

Implementation:

• Use a Text Input control:

If(!IsMatch(PasswordInput.Text, "^(?=.*[A-Za-z])(?=.*\d)(?=.*[@$!%*?&#])[A-Za-z\d@$!%*?&#]{8,}$"), Notify("Password must be at least 8 characters and include letters, numbers, and special characters.", NotificationType.Error))

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11. File Upload Validation

Scenario: Restrict file uploads to specific types (e.g., .pdf, .docx).

Implementation:

• Use a File Attachment control:

If(!EndsWith(FileAttachment.FileName, ".pdf") && !EndsWith(FileAttachment.FileName, ".docx"), Notify("Only PDF or DOCX files are allowed.", NotificationType.Error))

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12. Conditional Field Validation

Scenario: Validate a field only if another field meets a specific condition.

Implementation:

• Use an If statement with multiple conditions:

If(Dropdown.Selected.Value = "Other" && IsBlank(TextInput.Text), Notify("Please specify details for 'Other'.", NotificationType.Error))

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13. URL Validation

Scenario: Ensure a valid URL format.

Implementation:

• Use the IsMatch function:

If(!IsMatch(UrlInput.Text, "^(https?:\\/\\/)?([\\w.-]+)\\.([a-z\\.]{2,6})([\\/\\w .-]*)*\\/?$"), Notify("Please enter a valid URL.", NotificationType.Error))

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14. Decimal Validation

Scenario: Restrict input to only allow decimal numbers.

Implementation:

• Use the IsMatch function:

If(!IsMatch(DecimalInput.Text, "^\\d+(\\.\\d{1,2})?$"), Notify("Please enter a valid decimal number.", NotificationType.Error))

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15. Minimum Text Length Validation

Scenario: Ensure a text field contains a minimum number of characters.

Implementation:

• Validate using the Len function:

If(Len(TextInput.Text) < 5, Notify("Text must be at least 5 characters long.", NotificationType.Error))

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16. Maximum Text Length Validation

Scenario: Ensure a text field does not exceed a maximum number of characters.

Implementation:

• Validate using the Len function:

If(Len(TextInput.Text) > 50, Notify("Text cannot exceed 50 characters.", NotificationType.Error))

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17. Dropdown Selection Validation

Scenario: Ensure the user selects an option from a dropdown.

Implementation:

• Use the IsBlank function:

If(IsBlank(Dropdown.Selected.Value), Notify("Please select an option.", NotificationType.Error))

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18. Custom Date Range Validation

Scenario: Ensure the selected date falls within a specific range.

Implementation:

• Validate using the If function:

If(DatePicker.SelectedDate < DateValue("01/01/2023") || DatePicker.SelectedDate > DateValue("12/31/2023"), Notify("Date must be within the year 2023.", NotificationType.Error))

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19. Character Case Validation

Scenario: Ensure text is entered in uppercase.

Implementation:

• Use the Upper function:

If(TextInput.Text <> Upper(TextInput.Text), Notify("Text must be in uppercase.", NotificationType.Error))

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20. Multi-Select Validation

Scenario: Ensure at least one option is selected in a multi-select dropdown.

Implementation:

• Validate using the CountRows function:

If(CountRows(MultiSelectDropdown.SelectedItems) = 0, Notify("Please select at least one option.", NotificationType.Error))

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21. Cross-Field Dependency Validation

Scenario: Ensure a field is filled based on another field’s value.

Implementation:

• Use If to check dependencies:

If(IsBlank(TextInput2.Text) && !IsBlank(TextInput1.Text), Notify("Field 2 is required when Field 1 is filled.", NotificationType.Error))

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22. Alphanumeric Restriction

Scenario: Ensure text contains only alphanumeric characters.

Implementation:

• Use the IsMatch function:

If(!IsMatch(TextInput.Text, "^[a-zA-Z0-9]+$"), Notify("Only alphanumeric characters are allowed.", NotificationType.Error))

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23. Exact Length Validation

Scenario: Ensure input is exactly a specified length (e.g., 10 characters).

Implementation:

• Use the Len function:

If(Len(TextInput.Text) <> 10, Notify("Input must be exactly 10 characters long.", NotificationType.Error))

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24. Restricted Words Validation

Scenario: Prevent input of specific prohibited words.

Implementation:

• Use IsMatch with a word list:

If(IsMatch(TextInput.Text, "(badword1|badword2)"), Notify("Prohibited words detected.", NotificationType.Error))

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25. Minimum Items in Gallery Validation

Scenario: Ensure a gallery has a minimum number of selected items.

Implementation:

• Use the CountRows function:

If(CountRows(Gallery.SelectedItems) < 3, Notify("Please select at least 3 items.", NotificationType.Error))

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26. Overlapping Time Validation

Scenario: Ensure no overlap in time entries.

Implementation:

• Use LookUp to check for overlaps:

If(!IsBlank(LookUp(DataSource, StartTime <= ThisItem.EndTime && EndTime >= ThisItem.StartTime)), Notify("Time entries overlap.", NotificationType.Error))

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27. No Leading or Trailing Spaces

Scenario: Prevent leading or trailing spaces in text.

Implementation:

• Use the Trim function:

If(TextInput.Text <> Trim(TextInput.Text), Notify("No leading or trailing spaces allowed.", NotificationType.Error))

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28. Positive Number Validation

Scenario: Ensure input is a positive number.

Implementation:

• Use the Value function:

If(Value(TextInput.Text) <= 0, Notify("Please enter a positive number.", NotificationType.Error))

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29. Weekend and Holiday Restriction

Scenario: Restrict weekends and predefined holidays.

Implementation:

• Use Weekday and a holiday list:

If(Weekday(DatePicker.SelectedDate) in [1, 7] || DatePicker.SelectedDate in HolidayList, Notify("Weekends and holidays are not allowed.", NotificationType.Error))

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30. Max Number of Attachments

Scenario: Restrict the number of files attached.

Implementation:

• Use CountRows:

If(CountRows(FileAttachmentControl.Attachments) > 5, Notify("A maximum of 5 files can be attached.", NotificationType.Error))

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Conclusion

Validations on Power Platform are the assurance of data and a better user experience. You can apply multiple validations based on your application with PowerFX formulas and creative control settings. Accurate validation does not only protect your data but it also builds trust with the users.

What other checks are you missing? Comment below with any thoughts!

Finally, I was able to organize a PowerPlatform User Group in Kathmandu. The Power community is very much growing in Kathmandu and I’ve met some professionals during community events. However, it’s really tough to have them or anyone we don’t know to connect with each other. So I hope the group will work as a platform to connect everyone. This group is centered around Kathmandu for everyone working in PowerPlatform. We want to bring together everyone working in PowerPlatform in Kathmandu and learn from each other.

Power Platform User Group Kathmandu – Power Platform Community (microsoft.com)

The plan is to meet quarterly, share, go over the latest updates to Power Platform, help new users get started, and explore specific topics in detail. Everyone is welcome to join the event. And feel free to reach out.

Power Platform user group is to gain the education and support you need to build custom business apps that connect to your data and work across web and mobile. Attend in-person meetings where you can work with others in your industry to see how this no code/low code option has transformed the way they do business.

I’m honored and grateful to announce that I’ve been named a FastTrack Recognized Solution Architect, joining a group of 27 others from around the world.

FastTrack Recognized Solution Architects | Microsoft Power Platform

The Power Platform product innovation team bestows this distinguished award for regularly demonstrating broad architecture experience and delivering high-quality solutions for customers during project engagements.

It means a lot to me to be included alongside great industry leaders. I want to express my gratitude to Microsoft, especially the product engineering team for recognition! I want to thank my team and the clients for having their faith in me and given me the ability to show my skills and do what I enjoy the most!

Have you faced trouble when you use “When a record is created, updated or deleted trigger”? In my case, it took a long time to trigger or sometimes doesn’t trigger at all. It worked for Depreciated Dynamics connector but with the CDS connector, it seems to be an issue.

I switched to using Service Principal for connecting with the PowerAutomate and it greatly solved this issue while I couldn’t find any official documentation which mentions this solution though.

What is Service Principal?

PowerAutomate or any automation tool required privileges to access data. In order to access data, we use connections in PowerAutomate. And usually, with PowerAutomate, it’s more convenient to use a user account to set up a required connection but it comes with its own baggage. With service Principal, you create an application within Azure Active Directory, which is authorized to access resources or resource groups in Azure and the assign security roles to that user.

Why service principal?

• Removes dependency from a user account.
• Provides better security and keep the access limited to the application rather than a use.
• Make it configurable for the minimal permissions required by the flow and ensures the flow actions are not tied to a specific human user.

How to connect to service principal?

When creating a PowerAutomate, you can click on Connect with Service Principal.

You need to provide Client ID and Client Secret along with Tenant Id to establish a connection. You can check below to see how you can do that.

How to create service principal?

For creating a service principal, you need to register an app in Azure and give the access to that app to access data for user impersonation.

• Go to portal.azure.com
• Search for Azure Active Directory or click from the Azure Services list.

• Go to App registration to register an app.

• Register an application. Give a suitable name and Select a supported account type, which determines who can use the application. Under Redirect URI, select Web for the type of application you want to create. Enter the URI where the access token is sent to.

• You can get the Client ID and Tenant ID from the overview screen.

• For client secret, click + New client secret and generate a secret. Copy the secret and put it into your PowerAutomate connection and select user impersonation.

• You need to provide API permission to access Dynamics 365 Data. Go to + Add a permission, Click on Dynamics CRM.

Creating a application user to impersonate.

• Go to Advanced Settings

• Click on Settings > Security > Users.

• From the view selector, select Application user.

• Click + New
• Select Application user from the form selector.

• Paste the Application ID of the registered App on the Application ID field.

• And give the appropriate security role to this user.
• And voila you’re done.

Cascade Style Sheet or CSS in PowerApps is a capability that I wish will be part of a core feature of PowerPlatform someday. CSS has gone far past mere aesthetics to create unparalleled versatility. CSS is not only used, contrary to common opinion, to provide a web page with a simple style to make it appear more appealing. There are lots of other things that one can also do with CSS. 

With PowerApps, we wish there is a direct method to apply CSS to the App that we are building. Anyone who knows WordPress can feel that a simple additional CSS feature that comes with it empowers us to optimize every visual element on your site.

While Actual CSS is not possible, there are few things that we can do. 

1. Create a pseudo CSS by creating an object and defining styling values.
2. using inline CSS in HTMLText  

Create a pseudo CSS by creating an object and defining styling values

In this example, we will learn how to create pseudo CSS for button control in the PowerApp.

• Go to App in the Tree View and select OnStart Property.
• Create a style object on the OnStart Property.

Set(ButtonCSS, {
FontFamily: Font.'Segoe UI',
BackgroundColor: RGBA(127, 178, 57, 1),
BorderThickness: 1,
Color: RGBA(255,255,255,1),
Padding: 8,
TextAlign: Align.Center
})

Now create a button and set values of ButtonCSS in the property of the button.

Using inline CSS in HTMLText  

An HTML text control is a control in PowerApps that shows plain text and numbers and converts HTML tags, such as non-breaking spaces. Sadly, we can’t define global CSS in the HTML text control, but the best thing that we can do is define inline CSS.

As a workaround for setting global CSS, you could set global variables in the OnStart method.

Set(myStyle, “color:blue;font-size:46px;”)

Then in the HTML text control…

"<p style='"&myStyle&"'>
      I'm a big, blue, <strong>strong</strong> paragraph
    </p>"

And that’s it. This is how you can somehow implement the CSS like an attribute in PowerApps. We expect more to come on the platform itself in the future, but I hope it works out as a workaround for now.

I was working on one of my PowerApps projects where there were some fancy design requirements to be implemented. While working on it, I found that there is a good enough inconsistency in changing the Icon background color of the controls that are available in the PowerApps.

In this article, I am writing about all the different ways you can change Icon Background color of all the controls in the PowerApps.

What is Icon Background color?

On the right side of DatePicker, Dropdown and ComboBox, there is a icon, clicking on which you’ll get calendar, list of items depending on which control it is. The background of that section is pretty easily but inconsistent so can be tricky.

Changing Icon Background in different Controls.

1. Date Picker: You can go to property selector of the DatePicker control and put the color code in the IconBackground property. You don’t have option to change it from the right side property panel.

2. DropDown & Combobox: You can change it from the ChevronFill property from the property selector. You can also change it from the right side of the property panel and select the color.

Fews days back, I saw a tweet seeking people interested in creating a tutorial of a Christmas app for kids. I replied over that tweet. With that I connected with Rory of PowerApps4Kids, I pitched him the idea of the piano where we have to play the note of the Jingle Bell correctly. And if you play the whole notes correctly then you have Santa at your windows.

Are there any people out there that could create videos for creating SIMPLE Christmas Apps "From Blank" – Max 25-30 minutes. We are launching a course VERY SOON and would like it to be community led. @mrdang @83_laney @crmindian @AzureRory #poweraddicts pic.twitter.com/2w4fqigZpY

— PowerApps4Kids (@PowerApps4Kids) November 19, 2020

The way, I approached this is. First, there are a couple of objects that you need to place on screen.

• Image Control:
  • Image of the window in the background
  • Image of Santa
  • Image of Mery Christmas
• Button Control:
  • The piano keys
  • Reset button
• Label Control:
  • To show the key to press
• Audio Control:
  • That plays the keynotes
• Gallery:
  • To place button controls

You can find all the required media sources at Games/SantaPiano at master · powerapps4kids/Games (github.com)

Place Image of Window in the canvas. Go to Insert>Media>Image. On its Image property set value as “https://raw.githubusercontent.com/powerapps4kids/Games/master/SantaPiano/image.jpg” and set its Image position as Fill

My original idea was to place all the keys at once. Rory gave a clever idea of using a gallery to place all those keys in a gallery so that there is less copy-pasting of codes to each key. Insert a gallery into the canvas name it as galNotes. Go to Insert > Gallery > Horizontal and set its Items as

["C","D","E","F","G","A","B"]

Inside the gallery, add the button. Change its background fill as white. And set the text property of button as

ThisItem.Value

Add label with fill as Black to show black keys. Though it won’t be functional. You can use button and use the notes for them to make it functional though.

Insert a audio media set its Media property as

"https://raw.githubusercontent.com/powerapps4kids/Games/master/SantaPiano/"&galNotes.Selected.Notes&".mp3"

Now, on the Start property of the Audio control, we set its value as gvStartAudio

Select the button on the gallery and change its onSelect Property as

Set(gvStartAudio, false); Set(gvStartAudio,true)

We are setting it to false and back to true. This changes the value of gvStartAudio, making the Audio trigger since it has gvStartAudio on its start. If you have it set to true, it will play once and won’t play again.

We create label where show the code to display. On its Text

Last(FirstN(["E","E","E","E","E","E","E","G","C","D","E","F","F","F","F","F","E","E","E","E","E","D","D","E","D","G","E","E","E","E","E","E","E","G","C","D","E","F","F","F","F","F","E","E","E","E","G","G","F","D","C"],isCorrect)).Value

Now, we add an extra function to the piano key to check whether we are pressing the right keys. So, the final code looks like this.

Set(gvStartAudio, false); Set(gvStartAudio,true); If(ThisItem.Value=LabelNote.Text,Set(isCorrect,isCorrect+1)

We need to set an initial value for isCorrect so go to App on the left and on its onStart Property put this function

Set(isCorrect,1)

When we press the right keys the santa would appear, you need an 52 notes to be played correctly. So, Insert the image of Santa and Merry christmas. After that on its Visible property you can put following function.

isCorrect>51

This will show santa where the correct notes are played. And it will appear. In order to make it more interactive, may be you can change the color of highlight keys by changing its fill if thats the right keys. If(Self.Value=LabelNote.Text, Gray, White)

In conclusion, you get a cool Piano Santa Christmas app to play with. The whole course will be available with some other courses at Power Apps 4 Kids – Big Kids and Little Kids . You can also check PowerApps4Kids youtube channel to check Rory teaching you to make this app.

Microsoft has finally renamed “Common Data Service” to “Microsoft Dataverse” and “Project Oakdale” to “Microsoft Dataverse for Teams” after briefly calling them Dataflex and Dataflex pro. In this article, we will discuss what Microsoft Dataverse for the Team is, how it differs from Dataverse, and many possibilities it drives.

Microsoft Dataverse is a data storage platform that acts as the foundation for PowerPlatform. Microsoft Dataverse for Teams is a subset of Dataverse that inherits much of its features. Microsoft added these low-code/no-code components within Teams to position it as a platform for all work forms, not just limiting it as a communication app.

Previously, Microsoft Teams could use Microsoft Team Toolkit for Visual Studio and VS Code to build teams app. While you can continue to do that, you can leverage the power of PowerPlatform to develop quickly.

Following are the differences between a Dataverse for Teams and Dataverse table features.

Feature	Dataverse for Teams	Dataverse
Basic data types	Yes	Yes
Advanced data types (customer, multiple transaction currencies)	No	Yes
Common Data Model	Coming Soon	Yes
Relational storage	Yes	Yes
Non-relational storage (logs)	No	Yes
Managed data lake	No	Yes
File and image support	Yes	Yes
Find, filter, sort	Yes	Yes
Advanced and relevance search	No	Yes
Mobile offline	No	Yes

So, what can you do with Microsoft Dataverse for the Team?

With Microsoft Dataverse Teams, you can now use almost all the features of PowerApps, PowerAutomate, Virtual agent, and PowerBi. That means you can create, run, share app, bots, and flows inside the Teams.

You will also get a storage capacity of 2GB per Team with 1 million records. With Dataverse in Team, you get the ability to build, populate, and query data. You can create multiple tables, add fields to them, and define the relationship of tables with each other. You can upgrade Dataverse for Teams to Dataverse if the company needs additional features, such as more granular protection and governance control or capability above approximately 1 million.

It also comes with security that’s easy to use and aligned with approaches used in Teams with a focus on Owners, Members, and Guests.

Each Team has it’s Dataverse environment. If you create tables in the Teams and go to the admin center to check, you can figure multiple Environments listed with Environment type as Microsoft Teams.

Limitation with Teams

• With Dataverse for Teams, there is a limit in storage capacity, 1 million rows or 2 GB. 
• You have a limit of creating 500 Teams with a Dataverse environment.
• You can’t share Power Apps outside the Team it is built.
• You can share Power Virtual Agents with an entire organization, but the system will also remove the app/flow/bot if you remove the Team.
• You can’t use “Premium connectors” unless you have a license to use it. And these licenses can be too expensive.