The IsBlank function in Power Apps is used to determine whether a value is blank or not. This function is particularly useful for checking whether fields are empty, whether controls contain data, or for validating user input.
PowerApps – IsBlank() function Syntax
- Value: The value, control, or data field to check for blankness.
Notes:
- Empty Strings vs. Blank: Remember that IsBlank checks for both Blank() and empty strings. An empty string ("") is considered blank.
- User Feedback: Provide clear feedback to users when fields are left blank, guiding them to fill in the necessary information.
- Form Validation: Use IsBlank to check if required fields are empty and display error messages or disable submit buttons until all required fields are filled.
PowerApps – Check If a Text Input is Blank
Suppose you want to check if a Text Input control is empty.
- Add a Text Input Control:
- Insert a Text Input control named TextInput1.
- Add a Label Control to Display the Result:
- Insert a Label control.
- Set the Text property of the Label to:
If(IsBlank(TextInput1.Text), "Input is blank", "Input is not blank")
This will display "Input is blank" if the TextInput1 control is empty, and "Input is not blank" if it contains text.
PowerApps – Check If a Variable is Blank
Suppose you have a variable and you want to check if it is blank.
- Add a Button Control to Set the Variable:
- Insert a Button control.
- Set the OnSelect property of the Button to:
- Add a Label Control to Display the Result:
- Insert a Label control.
- Set the Text property of the Label to:
If(IsBlank(MyVariable), "Variable is blank", "Variable is not blank")
When the button is clicked, it sets MyVariable to blank, and the label will display "Variable is blank".
PowerApps – Use IsBlank function with Data Fields
Suppose you have a collection named Products and you want to check if the Description field of the first product is blank.
- Create the Collection:
ClearCollect(Products,
Table(
{ProductID: 1, ProductName: "Laptop", Description: "High-end gaming laptop"},
{ProductID: 2, ProductName: "Tablet", Description: ""},
{ProductID: 3, ProductName: "Monitor"}
)
);
- Add a Label Control to Display the Result:
- Insert a Label control.
- Set the Text property of the Label to:
If(IsBlank(First(Products).Description), "Description is blank", "Description is not blank")
This will display "Description is not blank" for the first product because its Description field contains text.
PowerApps – Check If a Dropdown Selection is Blank
Suppose you want to check if a user has made a selection in a Dropdown control.
- Add a Dropdown Control:
- Insert a Dropdown control named Dropdown1.
- Set the Items property to:
["Option 1", "Option 2", "Option 3"]
- Add a Label Control to Display the Result:
- Insert a Label control.
- Set the Text property of the Label to:
If(IsBlank(Dropdown1.Selected), "No selection made", "Selection made")
This will display "No selection made" if no option is selected in the dropdown, and "Selection made" if an option is selected.