DRDhanasekar R Syncfusion Team December 31, 2018 11:38 AM UTC
Greetings from Syncfusion.
We have validated your query "Format string property of SfNumericUpDown". When we set "0" as a format string, then 0 will be considered as a Number for the SfNumericUpDown control. Whereas when we set format string as any other number or string, it will be considered as constants. Hence 0 gets changed when we change the SfNumericUpDown value by using + and - button.
For more information about FormatString "0", please check on the below given link from Microsoft.