How to select all the text on focus in the Xamarin.Forms Masked Entry control
This article explains how to select all the text on focus in Syncfusion Xamarin.Forms SfMaskedEdit by the following steps:
Step 1: Create a SfMaskedEdit control with all the necessary assemblies.
Refer to this Getting started documentation, to create a simple SfMaskedEdit control and configure it.
Step 2: By enabling the SfMaskedEdit controls’ SelectAllOnFocus property, you can select all the values when focusing on control, as shown in the following code sample.
[XAML]
<maskedEdit:SfMaskedEdit Mask="00000" SelectAllOnFocus ="True" Value="12345"/>
Output

See also
What are mask types in SfMaskedEdit
How to hide the prompt character
How to hide the clear button in SfMaskedEdit