How to Restrict Null Values in the SfNumberBox Control?

This section explains how to restrict null values in the SfNumberBox control using the AllowNull property.

Behavior of Null Value

By default, the SfNumberBox allows an empty or null value when the input is cleared, as the AllowNull property is set to true.

When AllowNull is set to false, clearing the input will reset the value to 0 instead of leaving it empty.

For example, if the Minimum value is set to 15 and AllowNull is true, clearing the input will result in a null value in the SfNumberBox.

XAML

<editors:SfNumberBox HorizontalAlignment="Center"
                    VerticalAlignment="Center" 
                    Value="10" 
                    AllowNull="False" /> 

C#

SfNumberBox sfNumberBox = new SfNumberBox();
sfNumberBox.HorizontalAlignment = HorizontalAlignment.Center;
sfNumberBox.VerticalAlignment = VerticalAlignment.Center;
sfNumberBox.Value = 10;
sfNumberBox.AllowNull = false; 

Conclusion

I hope you enjoyed learning about how to restrict the change in value of the NumberBox control.

You can refer to our WinUI NumberBox feature tour page to learn about its other groundbreaking feature representations and documentation, and how to quickly get started for configuration specifications.

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